Sometimes, what can seem just a useful innovation in IT infrastructure can have a significant effect higher up. Containerisation is one of those things, and one of its experts outlined the how and why in a Software Development Community of Practice industry talk.
One of the advantages of being in Edinburgh is that we have quite the tech scene on our door step. Sometimes literally, as when one of the pioneers of the now ubiquitous Docker container technology turns out to work out of the Codebase side of Argyle House. And that’s not the only connection Adrian has with us; he used to work at the EPCC part of the university. Which made the idea of inviting him over for a general talk on Docker and containerisation both compelling and do-able.
Being in IS, but somewhat removed from actually running server software, I was about as aware of the significance of containers as I was hazy on the details. Fortunately, I was the sort of audience Adrian’s talk was aimed at.
Specifically, he answered the main questions:
What is a container?
A portable, isolated computing environment that’s like a virtual machine, but one that shares its operating system kernel with its host. The point being that it is a lot more efficient in image size, start-up times etc. than a virtual machine. Docker is a technology for making such containers.
What problem does it solve?
Containers solve the “it works for me” problem where a developer gets some software to work perfectly on her own machine, only to see it fail elsewhere because any of a myriad differences in the computing environment.
Why is it important?
Because it enables two significant trends in software development and architecture. One is the shift to microservices, which encapsulate functionality in small services that do just one thing, but do it well. Those microservices ideally live in their own environment, with no dependencies on anything else outside of their service interface. Container environments such as Docker are ideal for that purpose.
The other trend is devops- blurring the distinction between software development and operations, or at least bringing them much closer together. By making the software environment portable and ‘copy-able’, it becomes much easier and quicker to develop, test and deploy new versions of running software.
What’s the catch?
No technology is magic, so it was good to hear Adrian point to the limitations of Docker as well. One is the danger of merely shifting the complexity of modern software applications from the inside of a monolithic application to a lot of microservices on the network. This can be addressed by good design and making use of container orchestration technology such as Kubernetes.
The other drawback is that containers are necessarily not great at sharing complex states. Because each small piece of software lives in splendid isolation in its own container with its own lifecycle, making sure that everyone of them is on the same page when they work together in a process is a challenge.
Overall, though, Docker’s ability to make software manageable is very attractive indeed, and, along with the shift to the cloud, could well mean that our Enterprise Architecture will look very different in a few years’ time.
This week a group of us from Information Services are attending DrupalCon 2017 in Vienna and we are sharing our thoughts on the sessions we attend, recommending top sessions, and giving our key takeaways from our DrupalCon experience. Yesterday I posted our reactions to the first day of DrupalCon, and today we continue our DrupalCon reportage.
For two of our party, Tim Gray and Bruce Darby, this was a very exciting day as they were presenting a session on how we have used code sprints and collaborative development to build a community of users and developers around EdWeb. More on our first-time DrupalCon Speakers later!
As we embark upon our next big adventure, planning for the migration from Drupal 7 to Drupal 8 of EdWeb, the University’s central CMS, a group of us from Information Services are here in Vienna this week attending DrupalCon 2017. We are a small but diverse bunch of project managers, developers, sysadmins, and support staff who all play a part in building, running and managing EdWeb. For the next few days we’ll be sharing our thoughts on the sessions we attend, recommending top sessions, and giving our key takeaways – not the wurst variety – from our DrupalCon experience.
On Tuesday, we started DrupalCon the right way by attending the always entertaining Pre-note, followed by Dries Buytaert’s traditional Driesnote keynote presentation on the state of Drupal. We then set out on our different tracks, paths crossing at coffee and lunch, for the first intense but interesting day of DrupalCon sessions.
A few members of Information Services (and possibly beyond) attended Turing Fest at the start of August. Turing Fest describes itself as “four conferences in one; covering the product, strategy, engineering and marketing strands of technology. Spread over two days these four tracks shared knowledge and discussed topics at the cutting edge of technology with world-class engineers and technologists from a variety of industries.” It was held at the EICC here in Edinburgh.
Last week Development Services, in collaboration with colleagues in the University Website Programme team, helped run a code sprint with developers from around the University to work on fixes and enhancements for EdWeb, the Drupal-based content management system that underpins the University’s website. This post gathers some technology-agnostic thoughts on what we did to prepare, and how we ran our sprint, that might be of interest to anyone thinking about running a similar event.
Scotland JS was held on the 2nd and 3rd of June at Dynamic Earth in Edinburgh. There were numerous talks, a few interesting and/or useful of which I have detailed here.
On Friday, after the main conference ended, the conference centre remained open for the traditional post-conference code sprints, including the Mentored Core Sprint, which myself, Adrian Richardson and Andrew Gleeson attended for the first time. It turns out code sprints are addictive; we arrived at 9am intending to stay until mid-afternoon and were thrown out along with the last remaining sprinters when the building closed at 6pm! Fuelled only by water, caffeine and a very short lunch eaten at our code sprint table, each of us contributed something during the session to move Drupal 8 core along. Some other first-time sprinters were even lucky enough to have their first contribution made to Drupal in a live commit by Angela Byron (webchick) part-way through the code sprint! Having missed out on attending previous DrupalCon code sprints, it was great to finally have the opportunity to join in and contribute to Drupal!
Before arriving for the code sprint, we had prepared our laptops with a Drupal 8 install as well as the various tools described on the DrupalCon website, choosing the Acquia Dev Desktop as the quickest option to get started. We began the day at the First Time Sprinter Workshop to ensure we were all ready to go, and then moved through to the code sprint room, joining the many Drupalistas who had already settled down to coding. The mentor for our table was Rachel Lawson (rachel_norfolk on Drupal.org), who was friendly and extremely helpful in keeping us on the right track as we worked on the issues we picked up from the issue queue.
With Rachel’s guidance, Andrew and I managed to find a couple of related UI issues in Drupal core, specifically the Configuration and Structure administration pages, to give us some experience of using the issue queue. Neither of us had used the issue queue in anger before – the most I have done is re-roll a patch – so we chose something simple, and Rachel kept us right when it came to documenting what we were doing by commenting on the issues we picked up. When 6pm came and we had to leave, we had each uploaded a patch for the issue we were working on, and although neither resulted in a commit before we left, it was very satisfying to feel that we had moved both issues along and made a first small contribution to Drupal core. It was also comforting to see during the excitement of the live commit session in the afternoon that some of the committed changes were of a similar scale to those which we had made!
It was really interesting (and fun!) to take part in a DrupalCon mentored code sprint and witness first hand one of the best things about the Drupal community – the spirit of openness and collaboration that has made it a success. Every contribution, whether large or small, can add something, and every contributor can feel valued by the community for the part they play. I have already been looking at the issue queue for something else to pick up; the challenge will be to find the space and time to continue what we started at DrupalCon!
In a new approach to the early morning keynotes at DrupalCon, Day 3 began with two Community Keynotes presented by David Rosaz and Mike Bell. It was fantastic to see two community members being given the DrupalCon main stage as a forum to present on two very different topics that are important to them, and of interest to the community in general.
David’s presentation of his PhD research covered the different types of contribution made to peer communities such as the Drupal community, highlighting how important all types of contribution are to the continuing success of any such community, as well as how contributions can be encouraged and sustained to strengthen it.
Mike’s talk was of a much more personal nature, using his own experience of mental health problems to open a conversation on this difficult topic in a presentation that clearly chimed with many who were physically present in the audience or following the session online. It was inspiring to hear Mike speak so eloquently about his own mental health issues, how he has learned to accept and deal with them, and how others can do the same; such openness is rare, particularly in front of such a large audience, many of whom are complete strangers. The impact of his presentation, and the audience’s response to it, testifies not only to Mike’s bravery in standing up there to give such a personal talk, a nerve-wracking experience in itself, but also to the inclusive, supportive nature of the Drupal community.
Our experiences of some of the sessions from the final day of DrupalCon in Barcelona are outlined below. Thanks to Riky, Tim, Andrew, Adrian and Chris for contributing their thoughts on sessions they attended; any errors, omissions or misinterpretations in their edited notes are entirely mine. Most of the sessions mentioned below, along with many more interesting talks, are recorded and available on the DrupalCon YouTube channel.
The day finished with the Closing Session, where it was announced that DrupalCon 2016 will be in Dublin.
This session covered how a Drupal back-end can be decoupled from the front-end, supplying back-end APIs which allow an alternative front-end development tool to be used, a web development technique that is extremely prevalent today. The speaker acknowledged that Drupal does content management very well, but the website delivery tool out of the box does not always live up to the standard of the Drupal back-end. When constructing the model – adding a new content type – the process of getting fields set up and widgets created to configure the admin form is quick, but a lot of time is required to get the output right in the theming layer. Here, a Fully Decoupled model was proposed to address the limitations of front-end development in Drupal. The speaker noted that an alternative Progressive/Hybrid model could use Drupal to provide, for example, the header, footer and menu, with AngularJS for the rich, functional part of the page.
AngularJS is a framework for building decoupled front-end applications, chosen from the many alternatives for several reasons. The large development community makes it easy to get help, and the ready availability of lots of modules via ngmodules.org provides solutions for common problems that the community has already solved. AngularJS embodies OO concepts (dependency injection, etc.) to give a much cleaner codebase, and uses known recipes for laying out the structure of code and solving problems. The framework is supported by Google, which suggests that it should have longevity.
The format of the session was a whistle-stop tour of the tools required to prepare for using Drupal with AngularJS, followed by a demonstration of how the Drupal Views module can be used in conjunction with Drupal 8 RESTful web services to implement a back-end API which will generate view output in pure JSON form for consumption by a front-end application developed in AngularJS.
The following tools are required in the toolkit for a developer wishing to use the techniques demonstrated here:
a Task Runner to contain scripts that do particular tasks such as running tests or deploying code, in this case Grunt (Gulp and Broccoli would be suitable alternatives);
a Scaffolding tool, which takes away a lot of the work in initially building your application, in this case Yeoman (slush would be another option);
a Testing framework, in this case Karma, which comes with AngularJS (Behat is another option).
Having outlined the toolkit required, the speaker went on to demonstrate the stages of development, showing how straightforward decoupling Drupal can be once you have the right tools in place. The steps covered are described below, but this summary is no substitute for watching the excellent session recording and reviewing the code samples used in the demonstration.
1 Create “REST Export” display for view
A new display type for views is provided by RESTful web services, generating “just the data” in raw JSON format when the API URL is called. When the View is filtered, for example by ID, only filtered content appears in the JSON RESTful output.
2 Scaffolding for the AngularJS application
A scaffolding tool, Yeoman in this example, provides recipes which do the legwork of building the initial application. A simple command creates the base directories that are required for the web application, such as app for the code, dist for the compiled/minified files, required components for node & bower, etc. In this example, Node was used for the server side and Bower supplied the dependencies for AngularJS. A Grunt file defines the tasks which can be done on the project; an IDE such as PHPStorm may provide a pretty visual representation of this.
It was extremely impressive to see just how much of the repetitive process of getting an application up and running can be automated. The scaffolding process creates an empty application that is ready for code!
3 Set up the client side HTML to support the AngularJS code
The AngularJS application demonstrated was a single page application using index.html (HTML is the templating language for AngularJS). The compiled public version of this file differs from the version used during development because the Grunt task from the scaffolding recipe takes out unnecessary lines that are only for dev purposes when compiling the application. Again, automation simplifies the development and deployment process.
In index.html, an attribute on the body tag (ng-app) acts as a directive to provide scope for the AngularJS module that will provide functionality.
4 Create the server side AngularJS code
The app.js file in the AngularJS application contains router information to let the front-end know where to send requests. AngularJS uses dependency injection to inject the correct service at runtime; all that is needed is to provide the service name in arguments when defining the function. It was noted that HTML 5 mode needs to be enabled and base defined in order to use clean URLs, otherwise you get # in URLs. The $routeProvider configuration is used to tell AngularJS what template to use and what controller to use for each URL. The response handler is defined in a .js file, and a template file generates the application output using the RESTful web services output drawn from Drupal.
Et voila, with all of this in place, the Drupal 8 back-end is successfully decoupled and content consumed using a front-end AngularJS application.
5 Extend the app
Having covered the creation of the application, the demonstration went on to extend it, installing a new client-side package using Bower, which downloads a dependency that can then be configured in AngularJS app. This is done by including the dependency to the JS file for the package in the index.html file and adding the dependency to app.js in the section where dependencies are configured. Once the new client-side package is configured via these simple steps, it is ready to use.
The speaker briefly touched on equivalent functionality for Drupal 7, which does not have the built-in RESTful web services provided by Drupal 8. The services module can open up all nodes on the system via GUI config, and hooks can be used to override how the data is sent back. Alternatively, the RESTful module is code-based & gives more control over how the data is returned. The generator-hedley Yeoman script provides a scaffodling recipe to build a Drupal 7 back-end with an Angular application client, and includes Behat as the testing framework.
This session was very well presented and incredibly dense; the speaker not only provided background on the reasons for decoupling Drupal and how RESTful web services can be used to achieve this, but also gave a really good overview of how an AngularJS application is structured, showing just how clean the code can be and how well back-end and front-end elements are separated. Some developers in IS Applications are already exploring the possibilities of AngularJS in the context of uPortal development (see Unit testing AngularJS portlet with Maven and Jasmin and Making Portlets Angular); what we saw here indicates that we should definitely be pursuing this further. Decoupling allows the best tool to be used for the particular task in hand. The exciting potential is not limited to the Drupal context; given how much of the web is now being delivered using these decoupling techniques, we should start making the most of the flexibility they provide.
This was a Q and A session with a panel of 3 from larger Drupal shops these were:
Mike King, Project Manager with AnnerTech in Ireland
Dogma Muth, Project Manager from Amazee Labs in Zurich
Steve Parks, Wunderroot in London
The main takeaway from this session covers the question I raised on UX. What we did during the EdWeb project around UX was basically correct but too chunky; it could be refined to be more efficient by doing the UX in smaller chunks and earlier. Another improvement would be starting the wire-framing before the design is complete, the caveat being to do this where this fits. A second takeaway is around project communication, the two key words here are “early” and “transparent”!
Below is a summary of the questions and discussion. Also, check out the Wunder Way at http://way.wunder.io, where Wunderroot explain their project delivery strategy.
Q: How much do you explain to your clients about what Drupal is as a community?
All three said that they explain to their customers the principles behind the community, usually at the outset, and attempt to educate their clients and encourage their teams to engage and, where possible, contribute to the community. It’s also important to get their clients on board so that code can be fed back to the community after a project has finished where this is appropriate.
All three noted that there are different options for time recording from individual recording across a client/community split to having a percentage within a sprint for community-focused work. Also, community time spent during office hours needs to be met with the same amount of time outside of the organisation.
Q: How can small teams with a limited number of people and resources accommodate all the traditional Agile roles and processes?
In this situation it is important to concentrate on the most important parts and not try to do everything at once. Firstly, use communication as a tool to ensure that user stories correctly generate the deliverables to achieve the project objectives. With this in mind, it is important to understand why a feature is needed. The “so that” part of the story needs to clearly identify why something is wanted. Again on the communications front, stand-ups are the key to transparency within the project team.
Q: How is UX incorporated into your Agile process, in particular in projects with a large number of user stories and pressure to get things out the door?
Simple answer – wire-frames and process flow! Test often and early and keep it simple. Test on prototypes and allow sufficient time for this. It is good practice for the person doing the design not to pass the UX. There is no perfect way, but the key is dialogue! It is not recommended to wait until all the various design parts are finished before starting, and it’s important to keep asking what does the user really need. Find a way to confirm that by getting real end-users involved at the earliest stage possible. Also, UX starts at the beginning of a project with customer journeys.
Q: What is the ideal sprint length?
Two weeks, with a regular meeting structure including adequate time for planning and review. The whole team needs to be involved in sprint/iteration review. For some projects shorter sprint/iteration are a better fit, especially where faster demos are required; likewise under certain circumstances it may be better for a longer sprint/iteration duration.
Q: What is the best testing approach?
The key here is comprehensive automated testing, peer testing and of course dumb user (PM!) testing. It is also good practice to include testing in the definition of “done”, enforcing the idea that a user story is not done until testing is complete.
Q: How can things that were missed during discovery be picked up at a later stage, and how is this communicated with the client?
It’s easy: go back to the client at the earliest opportunity. Secondly, if this means extra scope then something has to give, and the client needs to prioritise. To avoid this happening, it’s important that the clients understand the principles of Agile and how it works. Change will always happen; it needs to be embraced and communicated, early and accurately, in order to allow prioritisation.
In this session, the speaker talked about how Pantheon successfully maintain a worldwide engineering team where 30% of engineers work remotely.
A distributed culture gives autonomy to function in space and time. It has several benefits to the company, such as higher availability of staff and greater coverage of time zones for supporting services, but also benefits staff members too, allowing greater flexibility in how they work, and freeing up time which would otherwise be spent on commuting to an office.
To assist in their distributed working, Pantheon use a variety of tools:
YubiKeys, a hardware key which needs to be plugged into a PC by a staff member, for 2 Factor Authentication.
However, there are things which aren’t as easy when working in a distributed manner. For Pantheon, trust, security and morale are very important; negativity and staff frustration can be amplified when working remotely. Pantheon introduced mandatory working from home days so that all staff could empathise with those who don’t work in an office. The bottom line is that you cannot beat actually getting together in person, but that doing so in a relaxed and more social manner can strongly aid working together remotely, even if only between different offices, by opening communication channels.
While we don’t have much distributed working in IS Applications, a lot of the tools were interesting and principles and techniques were discussed here which can be applied to people working in offices in the same city, but located in different offices and across different teams. We have equivalents for some of the tools demonstrated (HipChat, Skype for Business, Jira and Jira Agile), but using PagerDuty as an alerting system, 2FA hardware keys and extending HipChat with chat bots were all ideas which I will investigate further to see if they could be adopted within the department.
The session started by describing the old Continuous Integration workflow used by FFW; there was a single development environment, with all commits made to the master branch and then master was deployed to DEV, which caused shared resource problems and took too long for developers to configure their local development environment each time.
Their current workflow is now much better, and in some ways similar to the development performed for the Drupal projects: local Vagrant VMs are used, with feature branches in Git and automated testing on pull requests, BackTrac shows visual diffs between site versions and multi-node Munin for OS monitoring.
To enable their new workflow FFW produced CIBox, a standardised, preconfigured way to deploy the Jenkins continuous integration server. These are Vagrant Ubuntu VMs configured with Ansible and setup to use a GitHub project. The Jenkins VMs have Jenkins plugins, LAMP with SSL, CodeSniffer and JSHint code sniffers, SCSS-Lint for SASS file linting, security linters, Jetty and Solr, Selenium and Behat, and Drupal configuration instantly available.
While it is unlikely that we would use CIBox to replace our current Bamboo configuration, it was encouraging to see that many of the improved workflow techniques used by FFW are already being adopted by Development Services (Git with feature branches) or are soon to be investigated (local Vagrant development environments).
“Drupal is near impossible to test in an automated way; there’s too code and too much in the database,”
So began the confident speaker in a very exciting talk about the Probo Continuous Integration server. Traditionally in modern CI workflows, issues would be created and assigned to developers, they would create code and commit it to a feature branch, then this would be reviewed in DEV. However, despite these ‘best practices’, having multiple tickets worked on in one feature branch can mean cherry-picking pain if the Business is only happy that some of the issues have been successfully completed.
An alternative workflow proposed by Probo is to still have assigned tickets get coded on by developers and committed to a feature branch, but then have these feature branches get reviewed in their own temporary environments. This allows far more useful QA to be performed and avoids situations where only half a feature branch is ready for merging.
To enable this alternative workflow which distinguishes the tool from being “yet another CI server”, Probo was created. Available as both a hosted SaaS solution and as an open source project, Probo watches a GitHub project and automatically creates a temporary environment on the creation of a pull request. The technology it runs on is also interesting, using ‘fat’ Docker containers which treat an environment as a single unit.
The process of isolating individual features on a branch is actually similar to how feature branches were used in the project to develop the University’s new Drupal CMS, EdWeb. Each feature branch represented the functionality for a particular user story, but rather than having temporary environments automatically spin up, each branch was deployed to the Dev infrastructure, and only merged when ready. Automatic deployment of a temporary environment for each branch would have saved us having to manage the slot for deployment of a feature branch to Dev. Another difference is that QA by the business was carried out in a Test environment after merging with other features; whilst it did not happen often, we were still sometimes in a position where features that had been merged were not quite ready for production. The ability for the business to do their QA on the feature branch in a temporary environment would have been extremely useful. The session also highlighted a flaw in the new workflows being developed as part of our Python adoption.
This was a very entertaining session that I would encourage others to watch. Having a way to spin up temporary environments for QA is a very powerful technique which can be applied not just to Drupal, but to all of our development, and is something I intend to investigate further.
This session centred around Shoov, an open sourced visual regression tool developed by Gizra. Shoov provides both live monitoring of an application – as you would get from pingdom or 24×7 – and live visual regression testing. Testing for visual regression on the live site allows you to test for issues introduced by 3rd party elements, such as Facebook and Twitter widgets, as well as pick up on elements not rendering as expected, which cannot be spotted by conventional tests. It helps identify the cases where the site is broken as far as the users are concerned, but more conventional monitoring would report everything to be OK.
The session demonstrated how to use Behat to define your tests, and how to run the same test for multiple browsers (Chrome, IE, etc) on multiple platforms (Windows 7, OS X Yosemite, iPhone 5, etc) across multiple viewports (320, 640, 960, etc). You aren’t tied to Behat for testing; cucumber, casper.js and others are also supported.
The demonstration also covered how to exclude specific elements on the page that you always expect to differ from your base element, such as video, image carousels or other animated elements. You just use a CSS3 identifier to specify whether it should be excluded, hidden or removed before generating the diff image. Not only do you get a high contrast image diff, as Wraith generates (see also Fundamentals of Front-End Ops), but you can also get an image overlay where you can swipe to reveal one version overlaid on the other.
RDFa from schema.org is now in Drupal 8 core and this session showed what is currently possible with the help of contrib modules and what is in the pipeline with sandbox modules.
There is a lot of work going on to reduce the overhead both for site builders and site users in adding semantic markup to their pages. In Drupal 7 it is not a quick process to build a new entity and map its fields to RDFa properties.
With the RDF UI module it becomes very easy to generate a new content type based on a schema.org definition. If you want to create a new sporting event content type for example, you can specify that it is to be generated with a schema.org definition and you are just presented with a list of fields derived from http://schema.org/SportsEvent; then you just need to select those properties you want to use and generate fields for, and the entity is built for you with all the RDFa mapping done.
Keeping to the premise that you shouldn’t be replicating content in many places, there is a lot of effort going into tapping into external sources for taxonomies and marking those up with the correct RDFa automatically. Being able to have Entity Reference Fields take data from external APIs means you don’t have to replicate the effort in maintaining the taxonomy. For instance, you want to have the user select a genre for your music site, just point your entity reference field at the Genre API and offload that work while ensuring the semantic markup is also there to help search engines give intelligent results for searches by music genre.
When it comes to user-generated content and including semantic markup, there has only really been the RDFa Content Editor (RDFaCE) plugin for TinyMCE. But now we have a couple of extra buttons coming to CKEditor in Drupal 8 to allow users to apply semantic links to content – with dynamic lookups to Wikidata – to make it easy for you to, for instance, mark the word “Paris” in your content as a prince of Troy rather than have search engines interpret your content as relevant for the capital of France. There is a dynamic lookup based on your initial selection which you can further refine with additional terms to locate the correct “Paris” in the list and select that, and this is all without leaving your main workflow, making it more likely that content editors will actually use semantic markup.
This session covered lessons learned during the development of the ERPAL distribution. There are many uses for a distribution platform, which can start to introduce new challenges.
At the University our mechanism for supplying a Distribution profile matching the central Drupal CMS provision is still quite new, as is using Drupal in general. Although not widely used at the moment, there is quite a lot of scope for sites to implement sites based on the Distribution. It is however quite difficult to pre-empt how something so new will be used; we should remain aware of the potential is it matures in order to exploit it.
I attended this session with a colleague from the University Website Programme team, who manage the central Drupal CMS provision, EdWeb. Afterwards, the talk sparked a conversation about our own distribution and issues which we might have at the moment. The main thing that came out of this discussion is that a default config for our distribution site would be useful to make it easier for users to get up and running with working with it. We will follow this up by writing up some of the areas which have already arisen as needing some configuration for new users of our distribution. We can then identify how to incorporate this into this distribution itself, or even just into the one-click distribution provided on our central hosting system, which will be much simpler to achieve, and may be all that is required.
In this session, Dries talked mainly about the high and low points of the Drupal 8 project.
One of the main suggestions that came out of this was to release fewer things sooner, which is a strategy that will be adopted for future Drupal releases. It’s possible to see parallels between the Drupal 8 project and our project to develop the central Drupal CMS, EdWeb, giving some perspective on what we have done and achieved, and suggesting how we might proceed in future.
On Tuesday and Wednesday I posted some session summaries and comments from DrupalCon 2015 in Barcelona, where myself and a few colleagues are spending this week.
Day 2 of DrupalCon began with a short session celebrating those involved with Drupal. i.e. partners and contributors, highlighting the importance of Drupal community members contributing through sprints, followed by the morning’s Keynote with Nathalie Nahai. Nathalie spoke about web psychology, providing a scientific perspective on how people see and react to different aspects of web content presentation. Admittedly the theme was more applicable to those Drupal users who deal with marketing aspects of websites since it was concerned with how to get, and keep, the attention that you desire from your online audience. However, the principles apply equally well to any organisation or institution interested in engaging in the most effective way with visitors to their website.
The day continued with many more sessions across a broad range of topics. We also took part in a couple of Birds of a Feather sessions, one of the great features of DrupalCon, allowing members of the Drupal community with a common background or interest an opportunity to discuss face-to-face the issues they deal with, sharing their knowledge and experience and exploring potential strategies to resolve those issues.
Our experiences of some of Wednesday’s DrupalCon sessions are outlined below. Thanks to Riky, Tim, Andrew, Adrian and Chris for contributing their thoughts on sessions they attended; any errors, omissions or misinterpretations in their edited notes are entirely mine. Most of the sessions mentioned below, along with many more interesting talks, are recorded and available on the DrupalCon YouTube channel.
This session covered estimation and how to turn this critical project component from something that often leads to a project being perceived as a failure, into an accurate and more reliable part of the project process. A common issue within some organisations is that the person deciding the budget does not have the in-depth knowledge of the project deliverables required to make sensible decisions. A lot of work goes into creating an initial estimate without knowing the details of the deliverables; the “bid”, or in UoE terms the proposal estimate, needs to be made on the objectives, and it should be accepted that this is what the estimate reflects.
During the estimation process, it’s crucial to ask the right questions, to review and to explain the process outlined below (creating transparency), to define scope (get the business to say what they want), and to discuss and agree milestones.
The next part in the process is the discovery, which is best done with UX sketches, but this needs a designer! Rapid iterative design should be the approach, with sketch approval, continuing early tech planning with sketches in preference to wire frames; these sketches are not full set of requirements but enable rough estimates to be produced with a goal of +/- 40% accuracy. This provides an early indication of feature complexity and expedites prioritisation before moving on to wireframes, and long before anything is actually built. Wireframes must be fully approved before beginning the next stage.
The next stage is full Tech Planning, which involves larger group of people with a goal of achieving estimates with 10% accuracy, adding implementation notes. This stage comprises of several 1.5 – 2 hour meetings over a couple of weeks where the deliverables are broken down into tasks and these are estimated in hours. These sessions involve lots of discussion using a kind of low level poker estimation, but do not involve the business. The project manager can then create a budget breakdown based on the estimates; the results, which are now deliverables, are then shared with the business and recommendations discussed with them.
If the estimation is over the the available budget at this stage, the options are clear: descope, share work or find more budget.
During the build pay close attention to:
1. Large overspend on individual tasks;
2. New requirements (these need prioritisation!);
3. Weekly budget reviews and status check ins;
4. Demo as often as possible as this gets customers excited when they can see a concept come to life!
Finally at project wrap up the project should be within 10% of the estimate. It is worth noting that this process doesn’t really work when the client provides UX, or for time and materials projects – in that case just go Agile!
However, this approach does present two main challenges: it requires partner buy in, and essential meetings are difficult to schedule.
My takeaways from this session are the need to review and constantly update estimates as the project moves forward, the importance of prioritisation and defining what is actually needed, and creating transparency throughout this process. On suitable projects, this could involve additional soft milestones for estimation. Another takeaway relates to the estimation process itself, to make it more accurate. To do this we need to have more detail before committing to delivery. As project managers, we need to be strong and not press ahead when there is insufficient detail; without this, there is a tendency to estimate at an abstract optimistic level.
The old way to boost Drupal performance is to use the following technologies: memcache, APC/OPcache, Varnish, and server redundancy. We currently use all of these. We can now utilise elastic computing and containerisation to boost performance – as the presenter put it:
“this is not future technology, but present technology”
The speaker’s team was tasked to provide a minimum cost, automated, no-downtime hosting platform for 30 to 100 thousand Drupal sites. To do this, Amazon Web Services infrastructure was used to run a stack consisting of Docker containers, Nginx, MySQL, MongoDB, with Ansible for Configuration Management, a Node.JS administrative application, Apache Mesos as an abstraction layer, and Marathon and Chronos running on Mesos to allow it to control Docker containers and scheduled tasks. The end result gave a platform which could perform EC2 auto scaling and spin up Amazon Machine Images which contain the three used Docker containers (one for the admin application, one for Varnish, and a Drupal container which would be used for every site), while databases were shared with one per 500 sites to minimise their overheads using a clever method of table prefixing.
This was a fascinating, very technical talk which I’d recommend watching to anyone with an interest in successfully solving a huge, complex infrastructural project with modern technologies. Although we only have one Drupal site to run and not tens of thousands, some very useful advice was given based on the presenter’s experiences: Nginx is very flexible and PHP-FPM increases performance significantly (as we found with our own testing); centralised logging is vital; always use authentication on REST APIs; and the combination of cloud hosting and containerisation was excellent. If the task were to be repeated today though, one would likely use the AWS EC2 Container Service instead of Mesos and Marathon. Possibly the most important thing to remember
Platform.sh is a deployment platform originally developed for PHP applications which now also supports Python and node.js. It integrates with whatever git repository you want, as well as HipChat, Jira and other tools, allowing multiple applications to be pushed into one build, e.g. front and back-end applications, and appear under separate hostnames. Platform.sh handles all the DNS and varnish config to create these pop-up environments and replicates live database and configuration into your development area. It can also sanitise the database as it’s moved to strip out user passwords and email addresses, etc.
One really useful feature is the ability for developers to specify the version of PHP and control the php.ini file in YAML files. You can also specify which database should be set up for the environment.
The ability to control this non-code configuration and replicate a complex build process for all developers without them all needing the level of expertise to set up their own environment comes in very useful when working with multiple teams. This is especially true if external developers who don’t know your environment are involved.
The session also covered some of the performance gains that can be achieved running Drupal on HHVM (HipHop Virtual Machine), over PHP7 and PHP5.
Data breaches can be very expensive, so it is incredibly important to ensure that security consciousness is part of our mind-set in IS Applications. Breaches typically are not due to cracking encryption and hashes or exploiting unknown vulnerabilities, but rather human error. Thought should be given to the “CIA Security Triad” of confidentiality, integrity and availability. Security lists can be used to find out known vulnerabilities which need to be patched, these include: US-CERT and CERT-EU, LWN, Drupal, and security releases by Red Hat.
The main thing we took away from this session was not the quality of the advice, which was all very sensible (do backups, patch your servers and applications, use a Version Control Repository), but the practicalities of implementing that advice. Recommendations like using 2 Factor Authentication for our SSH keys are great, but we aren’t even using SSH keys for connecting to servers. Using enterprise login services so password hashes aren’t stored locally is also sound, but only if we were to use a technology like OAuth to allow it. We need to be doing more good practice when it comes to security; a greater security consciousness within IS Applications would be a great step in the right direction.
There are pros and cons to developing both locally (using VMs on a developer’s PC) and remotely (using Development servers provisioned by Development Technology). CASCADE is a new tool to streamline development workflows and add CI to local development. Effectively, it is extra code which uses Ansible to spin up and configure local Jenkins and GitLab Vagrant boxes and provide an interface to them.
While everyone in the audience was using Vagrant, very few had edited a Vagrantfile or run more than one Vagrant box at a time; a tool like CASCADE could provide developers with a simpler way to have a more advanced local CI environment. I don’t think its use would be appropriate to Development Services, but some of the ideas raised were interesting, especially as we are not generally using Vagrant for local development yet.
Integration testing is a topic that pops up regularly at DrupalCon, and in retrospect it was interesting to hear this talk on the same day as another talk on unit testing. This particular session focused on the use of BDD framework Behat for testing, coupled with Mink to simplify interaction with the browser emulator, provided in this case by PhantomJS (other browser emulators such as Selenium webdriver can also be used).
Whilst the speaker was very engaging and did give a decent high level outline of the different components, including the Gherkin language used to define Behat tests, the outline didn’t have a clear structure, which made it difficult to get a grasp on how each component fits into the bigger picture. That in turn makes it difficult to judge whether any/all of what was demonstrated would be useful in our context. It was also disappointing to see that whilst the talk description mentioned screenshot comparison, the only real mention of this during the talk was to say that PhantomJS was not the best tool for UI comparison (one attendee suggested wraith as an alternative). UI testing is something that we definitely need to explore further in the context of our Drupal CMS, and our current set of tools for automated testing (primarily Selenium WebDriver with test suites built in Java) may not be the best starting point. Unfortunately, although it was interesting to see Mink, which I hadn’t come across before, there was nothing in this particular talk to help us find the best approach to UI testing where there are gaps in our own test suites.
Whereas the earlier session I attended on Behat with Mink and PhantomJS was concerned more with integration testing, this session explored the principles of solitary unit testing, as contrasted with sociable unit testing, where the idea is to limit what is being tested as much as possible, essentially to test one thing without “crossing boundaries” such as writing to disk or reading from a database.
The speaker provided a very clear and interesting summary of the principles of unit testing, exploring aspects such as:
the importance of testing “one concrete class” (not counting value objects as these don’t have behaviour), using “doubles” to represent dependencies and objects returned by collaborators, thereby eliminating crossing of boundaries;
the stages of solitary unit testing, namely Arrange (setting up the context, e.g. any data required, before carrying out the test), Act (which ideally should call only one method) and Assert (to test whether the test passes);
the principle of always asserting last, and limiting each test to one assertion, which is really a general principle rather than a hard and fast rule – it was pointed out by one attendee and acknowledged by the speaker that sometimes it is necessary to break this principle;
ways of handling some of the complexity issues around unit testing, for example using ‘object mothers’ or ‘data builders’ to encapsulate setup, writing custom assertions to avoid multiple asserts in one method, and eliminating dependencies, all of which reduce the lines of code in the actual test and help to avoid “fragile tests” which break easily when something changes that isn’t directly related to the specific test;
the ability of solitary unit testing to highlight bad OOP code – if the test is difficult to write, the problem could be the code.
The speaker noted that solitary unit testing is not a catch-all, and will not always provide the most appropriate benefit. In our particular context, end-to-end integration testing is of greater importance than unit testing as we need to ensure that the complex set of contrib and custom modules and configuration settings which comprise our central Drupal CMS function correctly when deployed together in one of our deployment environments; integration testing using Selenium Webdriver is therefore incorporated in our automated deployment process.
Notwithstanding the focus of our own test suites however, the principles explored in this session such as clear code structure, isolating specific functionality, ensuring readability and clarity of tests, minimising what is covered by one test, and limiting the assertions performed, are equally applicable. It seems to me that many of these principles are a starting point for best practice regardless of the particular type of testing being performed. This was an excellent talk which provoked an equally interesting conversation between attendees and the speaker on when it is appropriate to bend or break the principles. I highly recommend watching the session recording to anyone with an interest in automated code testing.
The SmarTest module has been developed at the University of Seville, extending SimpleTest to improve automated testing for widely varying system configurations. With Drupal having a high scope of configuration variability, it can generate multiple test cases for different configurations which can be quite difficult to cover in testing.
As part of the studies performed by the speaker, Ana, and her team at the University of Seville, a diagram was drawn up showing the relationships between a set of modules (48 in their example). After querying how this was produced, I was told that it was quite an involved manual process and, without tools to assist, would be a fairly time consuming if we wanted to have the same thing.
With the tests that they ran across various modules, they found some direct (and possibly obvious) relationships between certain aspects. They found that module size (lines of code) as well as the number of commits on a module directly related to the number of faults found in the modules which they tested, i.e. More code and/or more commits produced more faults. However, the more contributors that there were on a module did the opposite and reduced the number of faults in modules. It was also found that migrating the same modules to a newer version of Drupal introduced more faults again.
The SmarTest module is something that could be interesting for us to run against the configuration of EdWeb, our central Drupal CMS. It aims, among other things, to highlight the most potentially problematic modules. However, the problem of Drupal being a “variability-intensive system” is not so much of an issue for us as we don’t really expect to vary our configuration drastically or often.
SVG is making a comeback now that Flash is dying off, and high resolution mobile and touch-screen tablet devices require vector graphics to keep logos and icons sharp while keeping file size low.
There are also some quite significant security risks if you allow users to upload their own SVG files, but that aside, you should be looking to SVGs rather than icon fonts for those vector icons now.
Configuration Management is a new feature to Drupal 8; in Drupal 7 the closest you have is the features module. This session was a quick tour of how configuration in Drupal 8 can be exported and imported using drush, how it is stored in YAML files, and where it is defined in custom modules.
Dependencies are fully managed in Drupal 8 through these YAML configuration files, and when dependencies are removed, the configuration is deleted. Demonstrations during the session showed how dependencies build up and apply as soon as you use them, for example, a role access filter being applied to a view.
Tips for best practice in changing these files and moving these files between environments were covered, as well as in-depth details of the Configuration Entity and third party settings.
This session explored the need to understand the requirements of editors and how to deal with the demands of content editors in Drupal.
Current limitations in Drupal were also highlighted, such as the disconnection between content and layout, which is not always a problem, and also how Drupal does not currently have revision history in content editing.
Quite simply, this “fastest Drupal ever” is Drupal 8.
Different caching options were discussed and it does look like, due to the issues seen in Drupal 7 and earlier, a lot of attention has been given to performance and customisation of caching options in Drupal 8, .
As mentioned in previous session notes, full page caching via reverse proxy such as Varnish is also possible in Drupal 8.
Birds of a Feather Sessions
Design and Usability Critiques
This was a great BoF discussion, not so much for new information, but confirmation that the UX approach taken during the EdWeb project was fundamentally correct, although the process of incorporating UX into Agile project needs to be lighter, take place earlier and be more frequent. We had 3 hour sessions with a large group of people, who at that time in the iteration were all under pressure to get the iteration completed.
Some recommendations to make Agile UX sessions more effective:
1. Run combined sessions with developers, business analyst, etc. but make them shorter;
2. Present results at these sessions;
3. Be clear about how UX sessions relate to prioritised stories;
4. Be clear up front about what questions the UX session should answer.
This session was set up by developers from the University of Adelaide in Australia and was well attended by representatives from Higher Education institutions in the UK and across Europe. The initial introductions showed that a wide range of Drupal experiences at various stages of maturity were represented, from the management of a small number of Drupal sites, through the distribution of a profile across more than 100 devolved Drupal sites, to the wholesale replacement of existing CMSs with a central Drupal service. As is so often the case during meetings between Drupal users having a common background, the main topics under discussion were pain points; what was apparent in the conversation that ensued was the commonality of these among the experiences of those present.
One area of particular concern was hosting, with almost everyone present agreeing that Universities often suffer from a peculiar fetish for internal hosting which can make it controversial to explore external hosting options. The main reason for this seems to be the desire to avoid exposing sensitive data, and that is clearly an important issue for many websites managed within the HE sector. The desire to keep things internal can make Drupal hosting especially difficult where there is a dependency for stability reasons on old versions of infrastructure elements such as PHP.
The approach which is being taken in Adelaide is of particular interest and something that we should explore further, especially given our own desire to look into the possibilities of configuration deployment and tools such as Puppet, Vagrant and Docker for automated deployment of the required server environments. The developers who set up the BoF have created an evolving platform for automated deployment of Drupal 8 to get around their internal hosting issues; they hope to collaborate on this with other institutions and ultimately make it available for wider use. We are not yet planning for Drupal 8, but the principles of how to manage deployment of Drupal in a devolved HE context are of interest regardless of the Drupal version being used. We have a relatively sophisticated means of deploying updates to the Distribution Profile that is associated with our central Drupal CMS, but we can do more with our automated deployment process in the admittedly more complex area of configuration and server deployment for the central CMS itself.
Another topic covered was role management – how to ensure that only the appropriate people can perform tasks such as generating a new Drupal site, or use functionality within a site. LDAP groups were discussed as one means of achieving this, with users automatically added and removed from roles within Drupal based on their LDAP group membership; this requires that groups be configured with the appropriate members, and that there are clearly defined mappings between those groups and roles in the CMS.
Overall this was a really interesting BoF. It was great to discuss both the positive aspects and common problems associated with using Drupal in an HE context, and to hear how other institutions are deploying and using Drupal. At the end of the session, contact details were shared and this will hopefully lead to further engagement beyond our meet-up in Barcelona.
On Tuesday I posted some comments on the start of DrupalCon 2015 in Barcelona, where myself and a few colleagues are spending this week. The major strands this year are Docker, performance and scalability issues, the Symfony framework in a Drupal 8 context, and using headless Drupal with an alternative toolkit to provide the front-end. So far it’s been really interesting to see how sessions on Symfony and Drupal 8 this year have progressed from last year’s DrupalCon in terms of the complexity of what is being covered. It’s also interesting to see how many attendees are using tools like Vagrant, Docker and Jenkins to take the pain out of manual configuration and deployment. We have been using automated deployment tools for application code for some time now in IS Apps; configuration management and automatic creation of server environments is something that could further streamline our deployment workflow.
Our experiences of some of Tuesday’s DrupalCon sessions are outlined below. Thanks to Riky, Tim, Andrew, Adrian and Chris for contributing their thoughts on sessions they attended; any errors, omissions or misinterpretations in their edited notes are entirely mine. Most of the sessions mentioned below, along with many more interesting talks, are recorded and available on the DrupalCon YouTube channel.
Drupal 8 makes use of many Symfony components, and this session covered the differences between the two frameworks to help decide which to use for projects. Drupal uses about a third of the Symfony components and you don’t need to know Symfony to develop Drupal.
Some differences are more obvious than others, such as while the application entry point in Drupal 8 is index.php, in Symfony it’s web/app.php and web/app_dev.php. These two entry points arise from the fact that Symfony enforces a programmatic toggle between Development and Production modes: you push generated code to production heads; you do not compile on production boxes.
Drupal uses the kernel a little differently and imposes stricter coding standards. For instance Drupal always uses the View event whereas this is discouraged in Symfony. Drupal 8 coding standards are quite strict in prescribing when to use YAML or Annotations for configuration. With Symfony configuration you are free to use PHP, XML, YAML or Annotations, although best practice is to pick one and stick to it.
Coming from Drupal 7, one of the fundamental differences in Symfony is that there are no functions; it’s all methods, with only a few static functions available. All meaningful logic in Symfony is in services, which are stateless objects.
Paths and routing are handled differently in Symfony and Drupal 8. In Drupal 8, you can only use module routing.yml files or events, not annotations, XML or PHP. Also, you don’t have path nesting or slugs in Drupal 8.
While both frameworks now use twig in the theming layer, when working in Drupal 8 you work with multiple twig files for each element, mirroring templating system in Drupal 7. Symfony templating uses only one file which extend twig files and override blocks defined in the parent twig file(s). Also Drupal always requires a render array; you don’t return rendered output directly in controllers.
Drupal has multiple APIs for storing content data, Symfony doesn’t have anything: you use Doctrine (or something else). Doctrine can only store primitive data and being a stand-alone PHP project has different event listeners from Symfony.
This talk highlights the fact that whilst Drupal 8 is using Symfony components, these are very much used with a Drupal flavour. Comprehending Drupal 8 and how it uses Symfony requires an understanding of what has gone before in previous versions of Drupal as well as knowledge of Symfony concepts and techniques.
In this session, Danish Digital Agency Adapt covered the background to their move from a Waterfall project methodology to an Agile approach, describing their experience of that transition and specifically targeting how they tackled estimation. Starting from a position where they were losing money on 50% of their projects due to inaccurate estimations and the need for their customers to prioritise scope, they adopted an Agile “light” methodology, only to quickly realise that with Agile it needs to be all or nothing.
The presentation continued with an outline of the process used to define user stories, use of planning poker, and the need for clearly defined roles and just-in-time management. The key to relative estimation, i.e. measuring feature size in story points not hours, is to involve all of the project team members in the process. Time boxed planning poker sessions, with limited discussion, allowed the knowledge level across the project team to be increased leading to more accurate forecasting. The iteration or sprint velocity was then calculated by breaking down the tasks (from development to testing) into the hours expected to take to complete. If a story took longer to complete than expected, the user story points associated with that user story did not change but this information was then used to forecast how much could be delivered within the project; this allowed the customer to prioritise what remained in the backlog.
The two main benefits derived from this change in approach to delivering projects was that, firstly, they were now in a position to keep to fixed budgets and secondly, knowledge was gained during the estimation process. However there were also negatives, primarily concerned with small projects where this approach has proved difficult to implement and there is often not sufficient time for people to become accustomed to this approach.
My main takeaways from this session are “Customise processes along the way” and “Know what you don’t know and accept that!”. Projects and customers (business units) are different and there is a need to refine and adapt the Agile process where experience shows that refinement is required. The more experience the project team have using Agile, the easier this process becomes. At the outset of a project, especially with larger scale projects, there are inevitably unknowns; it’s crucial to identify and accept these unknowns. As a project progresses, unknowns should become knowns and these can be requirements, risks or opportunities.
This was an engaging (if somewhat caffine fueled!) session. Drupal currently has a problem with the separation of configuration from content. Code is developed in DEV then pushed out to TEST, STAGING, then LIVE. Content, however, is created on LIVE and the other environments are refreshed from it. “Content” can be thought of as the database, which has tables for both the created content and the configuration, but as we want Drupal configuration to be developed in DEV and tested through the environments, what is really needed is for configuration to be treated like code.
Drupal 7 does not have a good way to deal with this, although the Features contrib module can be used, as we are doing in our own Drupal CMS, to make our configuration fully deployable through our automated deployment process. In Drupal 8, configuration management on a managed workflow seems to offer many benefits over the older version. Configuration is totally separated out into YAML files. These files can then be committed into Version Control System like code, providing accountability and the ability to audit configuration changes. All of this makes Continuous Integration much easier, and may make it configuration rollback possible. The YAML configuration files are imported into the database for added performance, allowing a more robust method of configuration over hook_update_n, or using the current feature module in ways for which it wasn’t strictly designed; drush has also been extended to work with this functionality.
This was an interesting talk which made some very useful suggestions for how configuration should be managed between environments when using Drupal 8, as well as how exceptions can be handled. This area should be explored further when planning for the Drupal 8 upgrade; we should look into replacing our reliance on the features module for exported configuration with the equivalent in YAML configuration.
One of the many sessions on what is new in Drupal 8 versus Drupal 7, this was an interesting talk giving a high level summary of the mechanisms for customising and extending Drupal 8. Topics covered were plugins, services, events and hooks. In Drupal 8, the principle for plugins is “Learn once, apply everywhere”, moving away from the inconsistencies between modules and how they are used by having plugin classes implement an interface, so there is a common approach. Services in Drupal 8 are very well decoupled and can easily be swapped out, for example for testing purposes. Event handling allows modules to react to Drupal application actions and/or conditions in a standard manner that is common in OOP rather than using hooks to react when something happens. Hooks still exist in Drupal 8, but are primarily for modifying metadata which has been gathered by other means, or to alter forms.
One interesting question that was raised at this session was how to determine whether what is needed to implement a feature is a plugin or a service. A useful way to decide this is to think about a service as something that you would usually only have one of for any Drupal instance, for example, a caching service.
This succinct outline of mechanisms for extending Drupal 8 highlighted the fact that these mechanisms are less specific to Drupal than in previous versions. Hooks remain, but whereas previously they would have been used for everything, Drupal 8 leverages Symfony to add new ways of doing things that help improve code structure and re-usability. The patterns and techniques are familiar from other contexts where OO is used, which brings a consistency and helps developers to better avoid the unnecessary, and at times frustrating and confusing, proliferation of different ways of doing things. These approaches also help with documentation – creating common patterns for implementing new modules means that Drupal developers are not so much at the mercy of how good the documentation for a particular module is. All of these factors should improve the development experience in Drupal 8.
As more application logic is being handled client-side, Front-end Ops is a response to the proliferation of front-end tools and frameworks. This session was not about the Drupal framework, but instead looked at tools for automating front-end development tasks, managing dependencies and generating scaffolding.
For scaffolding tasks, Yeoman was demonstrated. Yeoman recommends that your workflow involves Bower for dependency management and Grunt or Gulp for task automation. The session covered installing and using Yeoman, Bower, Grunt and Gulp as well as comparing the merits of Grunt and Gulp.
The talk covered the BBC’s Wraith, which leverages PhantomJS and SlimerJS to provide visual diffs of screenshots between two environments, as well as other visual regression tools, namely Huxley and PhantomCSS. There was also a discussion of the test rendering engines available: PhantomJS, SlimerJS, CasperJS and GhostLab.
Finally some of the front-end debugging tools available were covered, including Chrome DevTools Remote Debugging which allows you to connect a mobile or tablet to your desktop machine and use the development tools on the desktop browser to inspect the DOM, etc, on the mobile device.
This session gave a basic overview of the features and benefits of Docker and of infrastructure as code. It focused on Bowline as an easy way to get started using Drupal on Docker, offering great flexibility and minimum requirements via a suite of BASH scripts that can be included in your Drupal code repositories. The scripts add a method for container installation, and can also be used to “hoist” (start up) other containers at the same time for local development, such as a Behat container for testing. The aim is to simplify and facilitate the configuration and linking of containers for Drupal setups. This definitely looks like the way forward for the provisioning and support, at the very least, of our Dev environments. Taking the paradigm further than just sandboxes for development, the ability to move docker containers through an environment pipeline from Dev to Test and into Production was very interesting and worth further investigation.
While much of the session was used to introduce Docker, it was interesting to see the various methods, like Bowline, that are being used to enable developers to work with Docker containers as the next step on from Vagrant. It was also interesting that almost everyone in the room was using Vagrant and had Jenkins as their CI server, and about half were developing on Linux – none of which are currently true for Development Services in general.
Using Docker (or something similar) could be beneficial for us, mainly because it would give us readily available, standard and up-to-date environments for development or support use.
We do however already achieve something quite similar with virtual machine deployment environments on local machines.
As seems to be the current standard, this Docker session also started with the obligatory shipping metaphor-laden introduction to containerisation which I won’t repeat (see https://www.docker.com/whatisdocker for the official version). DrupalCI is a project to make it easier for developers to do local testing, and to enable testing of different combinations of PHP versions and database backends. It works by having a base Docker image, from which a PHP base image and a database base image are created. With only small adjustments containers with variations of these, like PHP 5.5 and PHP 5.6 environments, can be produced.
The talk also raised important security points which arise from using containerisation: one needs to think about running a private image registry (an ‘IS Apps Docker Hub’); SELinux should be used to reduce the possibility for malicious containers to break out into the host; and the responsibility for updating the images, and the running containers, is also vital.
While it is frustrating to keep seeing the same Docker introductions, it is interesting that so many sessions this year have been dedicated to the technology showing it is being used by many in the community.
In this session, Tine Sørensen drew on her years of experience in optimising performance for Drupal sites and troubleshooting scalability issues to highlight some of the techniques that can be used to diagnose issues, pick off the ‘low hanging fruit’ and achieve great improvements without great expense. There is no real value in spending 6 months rewriting some aspect of a module that is not performant if there is only a very small improvement at the end of that time. The recommended starting point when a performance issue is found is to collect data from the site, analyse it, choose where to apply effort – prioritising where ratio of effort to gains is the greatest, then repeat the process until performance is satisfactory.
The core message of this talk was the importance of collecting the data to demonstrate what is actually happening, and the huge gains in efficiency when pinpointing performance issues that can be achieved simply by using monitoring tools. Tine focused on New Relic as that is where her experience lies. As we found when we had external consultancy for our Drupal CMS project, New Relic is the tool of choice for monitoring Drupal and diagnosing performance issues; when using the Pro version, the tool has even more functionality such as granting XHProf-like profiling. Like ourselves in Apps, 50% of the audience were using New Relic for Drupal monitoring. Monitoring tools like New Relic can give an extremely useful picture of performance bottlenecks. For example, using the Pro version, it’s possible to see a list of PHP functions being called listed in order of execution time; this shows up any particular function that might be causing problems. A developer can then go straight to the function in question and analyse the code to identify any issues. We have used this technique ourselves whilst developing our Drupal CMS and it certainly can save hours, if not days, of time spent drilling down through XHProf reports.
Examples of quick wins were also provided, such as switching from GD to ImageMagick, disabling Views UI, tuning caching and tuning queries that are performing poorly. Of these, the GD/ImageMagick switch is the only one that was unfamiliar. It was particularly interesting to see that the server settings and tuning recommendations correspond to those we already use internally; it is useful to have our current approach validated by the speaker who is an experienced consultant.
For me, the main takeaways from this talk were that it is absolutely essential to understand what is happening on the servers when performance is poor, and that the less time you have to spend on collecting that data, the more quickly and efficiently you can resolve the problem. It’s also important not to simply throw hardware at a performance issue; that can resolve things in the short term, but ultimately it only masks the problem, particularly if that problem is not fully understood, with the risk that it could resurface in a more damaging way in future.
This session covered the new Plugin system in Drupal 8 which replaces the hook_info() and hook_info_alter() pattern. This is one of the areas where Drupal differs from other CMS’s and frameworks; Symfony bundles are hard-coded whereas Drupal plugins are configurable and discoverable.
Plugins do away with many of the Drupal 7 hooks, in favour of the new PluginManagerInterface model and examples of these in core were covered.
Plugin autoloading, dependency injection, service containers and annotations were all covered before going on to demonstrations of building your own plugins.
The session was very technical, covering low-level code samples in detail. It was a good companion piece to the earlier session on altering and extending Drupal 8.
The Drupal 8 theming layer has been re-written and now uses Twig as its template engine. Theme functions are pretty much done away with now and replaced with Twig templates. The theme process hooks are also done away with now that Twig is used. You still have the two levels of template_preprocess and hook_preprocess hooks, but now everything they return in the variables array needs to be a render array.
The session also covered writing Twig templates and how to extend Twig with your own custom functions/filters in Drupal.
Drupal enables Twig’s auto-escaping; the security issues around this, and how to mark strings as safe so they are not escaped, were also covered.
This session was presented by the Head of Sensio Labs (creators of Symfony), Sarah Khalil. It covered the components involved in processing a HTTP request starting with the front controller (app.php in Symfony, index.php in Drupal) passing the Symfony HttpFoundation request through HttpKernel.
The Routing component YAML files are named and located differently in Drupal, but in essence the process is unchanged for the router passing the request through the controller and on to returning an HttpFoundation response.
Symfony’s Event Dispatcher component was covered in some detail with examples of event listeners and subscribers, the differences between them, and examples of how Drupal core implements these.
After listing the seven kernel events that you should know together with the Symfony components used that Drupal uses, the Dependency Injection component’s three key concepts of service container, services and parameters were detailed.
Finally a quick look at the concepts in Twig, with the caveat that Drupal does not use all the features available in Twig.
This session, although fairly technical, was well presented by clearly very knowledgeable speakers and touched on upcoming technology such as service-worker (client-side caching), ESI and Big Pipe.
Content Delivery Networks are external, multi-sited hosts which enable content to be delivered with lower latency from caches local to the user. They can be used just for static assets (JS, CSS, images), and also for dynamic content, although the latter is far more complicated. As proven by our infrastructure with Varnish, delivering anonymous content from a cache is fairly simple as it rarely changes; this advanced session focused mainly on caching authenticated content with CDNs.
As we have seen in earlier DrupalCon sessions, Drupal 7 is limited in what it can offer in this conext; it can only use “max-age” caching, or scripted/manual purging of stale content from CDNs. Drupal 8 looks to have taken a big step forward in terms of the effects of caching on website performance, providing three main cache invalidation techniques:
cache tags, which show where data dependencies for caching exist;
cache contexts, which give the context of dependencies for requests;
cache max-age, as found in Drupal 7, which give the time dependencies of what is cached.
Together these enable placeholders and auto-placeholdering, whereby Drupal 8 “knows” what content makes up the page and so knows which can be retrieved from a CDN and which needs to be dynamically requested from Drupal.
Using this mechanism, it’s possible to perform Edge Side Includes with authentication being cached per session. This could be used with Varnish rather than a CDN, enabling us to cache a lot of our HTTPS traffic, which is where we are currently experiencing our worst performance. The demonstration of the response time improvements from caching user specific content was very impressive. While complicated, I strongly recommend that using Varnish for authenticated users is investigated when upgrading to Drupal 8. This would perhaps be one of the main reasons for considering upgrading when it is finally released.
BigPipe ( https://github.com/bigpipe/bigpipe ), a node.js framework which can be used with Drupal 8, was also demonstrated. It breaks up pages into smaller chunks so they can load asynchronously, decreasing the time for the first elements of page content to load.
This session dealt with a rather different approach to managing projects, albeit there is a caveat that this covers smaller pieces of work. Basically anything at all that can be deemed as not adding tangible benefit should be removed from the project. We all know that getting decision makers to make decisions quickly can be challenging. So the first thing is to identify your decision maker. In the example given the presenter, Jason Mark, relayed a project that was delivered within 4 weeks. The first week was used for requirements, design and templates and starting the build. The remaining three weeks involved working with the client/partner to test and refine what was delivered.
If this fast track approach is to work, it needs several things to fit, the main four being:
No hidden stakeholders;
The right people – low ego and ability to be flexible are key characteristics;
Technology needs must fit and the requirement needs must fit the technology.
If there are blockers, especially people, find ways to turn them into champions by using positive creative language.
The top takeaways from this session are twofold. Firstly, take a step back and look at the project in terms of the 4 points above. Can these points be answered positively? If not, what can be done to turn this around and make the process fit? Secondly, because this is a fast approach to turning a piece of work around, the planning will not be complete before the work starts. This makes change inevitable, which needs to be embraced at the outset and not seen as something negative. To repeat a quote attributed to Buddha,
“Change is never painful, only the resistance to change is painful”
Above all, only focus on things that add value! As Project Manager you can ask this everyday!
This session was about headless Drupal. Perhaps the only advantage for us with this is the security advantages of removing some front-end admin components. Alternative means of achieving what we require do however seem quite time consuming and careful consideration of the particular development context would be needed before going down the headless Drupal route.
This was an interesting session that would have benefited from demonstrating a concrete example. The material presented was somewhat abstract and the potential for an escalation in complexity and the associated infrastructure requirements of such a system seemed a little daunting without something to tie it to a real world example. However, a centralised logging system would be a great asset to IS Apps even beyond the context of Drupal and EdWeb. An ELK stack, in some incarnation, should be a serious consideration.
A disappointing session that was difficult to generalise from, and only seemed relevant in terms of the specific service that the speakers were trying to move into the Amazon Cloud. The Mollom spam protection system seemed far removed from anything managed by IS Apps. It was claimed that the switch to AWS reduced the number of alerts that were received by the Ops team, but no other metrics were presented in terms of savings to the business as a whole. The takeaway from this session seemed simply to be that you need to think differently about services in AWS due to the ephemeral nature of the server instances, these being discarded and new ones spun up any time configuration changed or applications crashed.
At the Lightning Talks session, there were 3 commercial companies pitching ideas and providing insight into their products and services.
This is a good looking and powerful tool which could be useful for us when working with PHP in Drupal. It has Drupal-specific functionality such as being able to track hooks across your codebase. It also incorporates Git functionality and provides a graphical means for diffing files as well as back tracking changes. In general it seems quite neatly put together and well thought out.