Free CI for your GitHub forks

How to build & test your feature branch for free on AppVeyor & Travis CI before submitting a pull request


I had an epiphany the other day when troubleshooting an issue with a pull request that I had submitted, which is that you can have AppVeyor and Travis CI (free CI/CD services for public repos) build & test your commits to your fork’s feature branch on push by simply enabling the repo in your AppVeyor and/or Travis CI accounts.  In this instance, my changes had worked on my Fedora image, but the build failed on Travis CI’s Ubuntu Trusty image.  Had I thought of this beforehand, I would have been able to detect and resolve the issue before submitting the pull request.  This is especially useful if you are attempting to help augment and/or optimize the project’s build configuration.

Also, you can implement this even if the project doesn’t use either of these CI/CD services or if the owners do not store the build configuration in the respective YAML file.  The caveat is that in either case, you would have to configure the CI services yourself.

To start building & testing a new project in AppVeyor, go here, and for Travis CI, go to your profile page.

Enable a new project in AppVeyor
Enable a new project in AppVeyor


Enable a new project in Travis CI
Enable a new project in Travis CI


So far, I have used this methodology to provide screenshots and build logs as evidence in a couple of pull requests.  I have also used this to create and submit a Travis CI build configuration for a project that was only using AppVeyor and demonstrated how it would work if merged.  Pretty cool, right?


CI/CD design decisions for a Microsoft PowerShell project on Travis CI

Per my previous post, this post covers my continuous integration / continuous deployment design decisions for my open source ArmorPowerShell project.

General Configuration

Building Specific Branches

You can whitelist and/or blacklist branches here, but I chose to build all branches in this project and included logic in the various scripts to limit actions prior to merging into master.

# whitelist 
    #- master

# blacklist


You can granularly define build stages as well as conditional builds based on criteria such as branch, release tag, et cetera in the Jobs section.  I have not implemented this so far.

    #- stage:


I recommend setting the Language to generic for scripting language projects (which is not listed in the Language documentation, but is briefly mentioned here), because all I needed for installing PowerShell Core was bash, curl, & apt for Ubuntu and homebrew for macOS, but there are a wide variety of choices if you require otherwise.

language: generic


You can also define specific runtime versions for certain applications.  If more than one runtime version is specified for the same item, a job will be created for each version.  I did not need to implement any of these for this project though.



In the Git section, you can specify a clone depth limit or disable cloning of submodules to optimize job performance.  As of 20171128, the default commit depth on Travis CI is 50, which should provide sufficient commit history for most projects with accommodation for job queuing.


Environment Configuration

Environment Variables

If you plan to test your open-source PowerShell project on multiple CI providers such as Travis CI and AppVeyor, I recommend defining a few global environment variables such as the ones listed below that abstract the CI specific variables to minimize the logic needed for handling each in your build scripts.  If you define a variable more than once, another job will be created for each definition.  You can also define matrix-specific environment variables in this section, or at the image level in the Matrix section.

# environment variables
 - MODULE_NAME="<insert module name>"
 - MODULE_VERSION="{set module version in build script}"
 - OWNER_NAME="$(echo $TRAVIS_REPO_SLUG | cut -d '/' -f1)"
 - PROJECT_NAME="$(echo $TRAVIS_REPO_SLUG | cut -d '/' -f2)"
 - secure: <secure string>


There are lots of terrific services and databases that are installed and available in each image should you need them.

# enable service required for build/tests
 #- cassandra # start Apache Cassandra
 #- couchdb # start CouchDB
 #- elasticsearch # start ElasticSearch
 #- memcached # start Memcached
 #- mongodb # start MongoDB
 #- mysql # start MySQL
 #- neo4j # start Neo4j Community Edition
 #- postgresql # start PostgreSQL
 #- rabbitmq # start RabbitMQ
 #- redis-server # start Redis
 #- riak # start Riak

Global Image Settings

You can define your build images at the global scope; however, I chose to use the matrix build image configuration as recommended here for multiple operating system build configurations, because it is cleaner.  For example, when osx_image is defined at the global scope, your Ubuntu builds will receive the xcode tag, even though it does not apply.

xcode tag assigned to Ubuntu Trusty build image

# Build worker image (VM template)
#- linux
#- osx

#sudo: required

#dist: trusty

#osx_image: xcode9.1

Build Matrix

The Matrix section allows you to customize each image that will build your code.  I cover most of these features sufficiently in the previous post, but the two that I did not are:

  1. allow_failures, which will permit the specified build image to pass regardless of any errors that occur.  I’ll likely never use this feature because it defeats the purpose of implementing continuous integration in my opinion.
  2. exclude, which prevents building specified images when you define combinations of environment variables, runtime versions, and/or matrix images.  I don’t foresee my scripting language projects being complicated enough to require this feature.
    - os: linux
      dist: trusty
      sudo: false
            - sourceline: "deb [arch=amd64] trusty main"
              key_url: ""
            - powershell
    - os: osx
      osx_image: xcode9.1
        - brew tap caskroom/cask
        - brew cask install powershell 
  fast_finish: true


In the addons section, you can define hostnames, prepare for headless testing, upload build artifacts, add SSH known hosts, et cetera.  I have not needed any of these so far for this project.


APT Add-ons

To install packages not included in the default container-based-infrastructure you need to use the APT addon, as sudo apt-get is not available.

For now, I have only used this to setup the Microsoft PowerShell Core package management repository and install PowerShell Core on my Ubuntu Trusty container image defined in my build matrix.

If the APT Add-ons step exits with a non-zero error code, the build is marked as error and stops immediately.

      #- sourceline: 

Build Cache

You can cache files and folders to preserve them between builds such as if you have low-volatility, large files that take a while to clone.  I did not.  Tabula rasa.

If the cache step exits with a non-zero error code, the build is marked as error and stops immediately.

# build cache to preserve files/folders between builds

Before Install

In a before_install step, you can install additional dependencies required by your project such as Ubuntu packages or custom services.

One important thing to be aware of is that matrix image instructions override global instructions.  Since I placed the homebrew commands to install PowerShell in the Before Install step of the macOS build matrix image, if I were to define a global Before Install step, the macOS build matrix image would ignore it.  Alternatively, you could use conditional logic in the global step if you only wanted to perform some instructions on a specific operating system, and some on all build images.

If the before_install step exits with a non-zero error code, the build is marked as error and stops immediately.



As of 20171128, there is no default dependency installation step for PowerShell projects on Travis CI.  In the install step, I chose to install and import the necessary PowerShell modules on all build images, and implemented it via a PowerShell script so that I always utilize the same logic in my AppVeyor builds with no additional configuration (ie: DRY).

If the install step exits with a non-zero error code, the build is marked as error and stops immediately.

- pwsh -file ./build/shared/install-dependencies.ps1

Tests Configuration

Before Script

You can run custom commands prior to the build script step.  I have not had a need for this step yet.

If the before_script step exits with a non-zero error code, the build is marked as error and stops immediately.



I call both my build script and test runner script here because non-zero error codes flag the build as a failure, but the build continues to run, which was what I wanted for these.  There is also an after_script section where I could have run my tests, but this step is run last, after the finalization after_success and after_failure steps (similar to the AppVeyor on_finish step), but also after the deploy steps.  Also, these three steps do not affect the build result unless the step times out, and I wanted both the build script and the test script to affect the build result.

- pwsh -file ./build/shared/build.ps1
- pwsh -file ./tests/start-tests.ps1

Before Cache

This step is used to clean up your cache of files & folders that will persist between builds.  I have not needed this yet.  Again, tabula rasa.


After Success / After Failure

You can perform additional steps when your build succeeds or fails using the after_success (such as building documentation, or deploying to a custom server) or after_failure (such as uploading log files) options.

I chose to build my documentation in the build.ps1 script in the script step instead of the after_success step, because I wanted failure to affect the build result in my project.

# on successful build

# on build failure

Deployment Configuration

There are tons of continuous deployment options available in the Deployment Configuration, such as Heroku, Engine Yard, and so many others, but I haven’t needed any for this project so far because I am handling all of the publishing from AppVeyor.  The continuous deployment tasks could have been implemented just as easily from Travis CI, I just happened to finish the AppVeyor integration first and my publishing tasks only need to happen once per build.

# scripts to run before deployment


# scripts to run after deployment

# after build failure or success


It took me approximately one email to get tired of build email notifications.  I recommend disabling it in the Notifications section as shown below.  Next, there are tons of free options out there, but I chose to create a free workspace for monitoring builds.  Travis CI has an app published in the Slack App Directory, and setup instructions can be found here.

 email: false
 secure: <secure string>


That’s it for now.  I have really enjoyed using the Travis CI platform so far, and feel much more confident in the quality of my project because of it.  Enjoy!

PowerShell Core on Travis CI

How to build, test, and deploy your PowerShell projects on Linux and macOS for free with Travis CI!

Last month, I started a new pet project of building an open-source PowerShell module for Armor, and one of the first goals that came to mind was that I wanted to ensure compatibility with PowerShell Core on Linux.  I had recently re-read Chris Wahl’s article: How to Version and Publish a PowerShell Module to GitHub and PSGallery with AppVeyor, and figured that there had to be a similar service for Linux, so I started looking around.  I found Travis CI rather quickly, and was pleasantly surprised to discover that they offered macOS images in addition to Ubuntu.

If you are unfamiliar with Travis CI, here is a solid description:

Travis CI is a hosted, distributed continuous integration service used to build and test projects hosted at GitHub. Travis CI automatically detects when a commit has been made and pushed to a GitHub repository that is using Travis CI, and each time this happens, it will try to build the project and run tests. This includes commits to all branches, not just to the master branch.

Restated, this means that every time you push new code up to your public repo, Travis CI (and/or AppVeyor) will build your project per your specifications, run any tests defined, and even deploy it if desired.  For free.  Build, test, and deploy on push for free.  How cool is that?

Now, one of the reasons that I am writing this article is that getting started with building & testing a PowerShell project on Travis CI was not intuitive.  AppVeyor and Travis CI were both designed for building, testing, and deploying programming language projects, not scripting language projects.  It took a lot of RTFM and a little trial & error to figure it out, but it was so worth it.  The following article covers some of my lessons learned in the process.  I hope that you find them valuable.

Getting started with Travis CI

  1. Sign into Travis CI with your GitHub account and accept the GitHub access permissions confirmation.
  2. Once you’re signed in to Travis CI, and we’ve synchronized your GitHub repositories, go to your profile page and enable the repository you want to build: enable button
  3. Add a .travis.yml file to your repository to tell Travis CI what to do.
  4. Add the .travis.yml file to git, commit and push, to trigger a Travis CI build:
    1. Travis only runs builds on the commits you push after you’ve enabled the repository in Travis CI.
  5. Check the build status page to see if your build passes or fails, according to the return status of the build command

Not too bad, right?  Don’t worry, there isn’t that much more even though the scroll bar indicates otherwise.

Install the Travis Client

The travis gem includes both a command line client and a Ruby library to interface with a Travis CI service.

You’ll need the Travis Client on your workstation for encrypting sensitive data such as access tokens as well as for linting (validating) your .travis.yml file.

Install Ruby


On Windows, we recommend using the RubyInstaller, which includes the latest version of Ruby

Mac OS X via Homebrew

Mac OSX prior to 10.9 ships with a very dated Ruby version. You can use Homebrew to install a recent version:

$ brew install ruby
$ gem update --system


Install the Travis ruby gem

Make sure you have at least Ruby 1.9.3 (2.0.0 recommended) installed.

You can check your Ruby version by running ruby -v:

$ ruby -v
ruby 2.0.0p195 (2013-05-14 revision 40734) [x86_64-darwin12.3.0]

Then run:

$ gem install travis -v 1.8.8 --no-rdoc --no-ri

Now make sure everything is working:

$ travis version

Customizing the build

Travis CI’s documentation of the .travis.yml file sprawls quite a bit as there are so many features available, so I’ll start with an example .travis.yml config file that should work for testing most of your open-source PowerShell projects on the Travis CI platform.  In my next post, I will provide a high-level overview of all of the available options that I found in the documentation for reference, as well as my design decisions for the ArmorPowerShell project.

Example .travis.yml config file

To start testing your open-source PowerShell project on macOS & Ubuntu, copy the contents below to a file named ‘.travis.yml’ in the base directory of your project.


language: generic

    - os: linux
      dist: trusty
      sudo: false
            - sourceline: "deb [arch=amd64] trusty main"
              key_url: ""
            - powershell
    - os: osx
      osx_image: xcode9.1
        - brew tap caskroom/cask
        - brew cask install powershell
  fast_finish: true

  - pwsh -f "${env:TRAVIS_BUILD_DIR}/install-dependencies.ps1"

  - pwsh -f "${env:TRAVIS_BUILD_DIR}/build.ps1"

  - pwsh -f "${env:TRAVIS_BUILD_DIR}/test.ps1"

  - pwsh -f "${env:TRAVIS_BUILD_DIR}/deploy.ps1"


  • The powershell executable name has been shortened to pwsh as of v6.0.0-beta.9.
  • There are a few lines that call PowerShell to execute a file, such as pwsh -f "${env:TRAVIS_BUILD_DIR}/install-dependencies.ps1" in the base directory of the project, fully-pathed through the TRAVIS_BUILD_DIR environment variable, but these are by no means necessary.  You could store these files in sub-directories, give the files different names, call commands instead of files, or do something else entirely- these are all just ideas to stimulate your imagination; however, whatever logic you define needs to be valid or your build will fail.

What does this .travis.yml config file do?

  • language: This defines the programming language that the build system should use.  I set this to generic, because I am building a scripting language project.  The generic setting is not documented in the Travis CI Languages documentation, but is listed in a few examples, such as this one.
  • matrix: The Matrix section allows you to customize each image that will build your code.
    • include: Include the specified image configurations.  All configurations defined for an image in the matrix will override the corresponding global configuration.  For example, I configured a before_install section in the osx image above, so if I had a global before_install section defined in the .travis.yml config file, the macOS image would skip it.  Excludes can also be defined for here more complex build topologies.
      • os: The operating system of the image.  As of 20171125, the two choices are osx (macOS) and linux (Ubuntu).
      • dist: The Ubuntu Linux distro image.  As of 20171125, the two choices are trusty (Ubuntu 14.04 LTS Trusty Tahr) and precise (Ubuntu 12.04 LTS Precise Pangolin, which is end of life).
      • sudo: This purpose of this setting is almost certainly not what you think.  Setting sudo to false in your Trusty images causes your build to be deployed to a container instead of a VM, which will start up and complete much faster than the VM image.  Unfortunately, as of 20171125, there is not a containerized option for macOS yet.  If you want or need to use an Linux VM image, set sudo to required.  I have had no issues with building or testing my code inside a container so far.  I will update the article if I discover a blocking issue, but I don’t expect to at this point since the PowerShell Core team publishes nightly builds on Docker Hub and of note, they also build on Travis CI.
      • addons: There is a lot that can be configured in the addons section, but for now, we’re only going to use this for the Trusty image to add the appropriate Microsoft software repository where the official PowerShell Core binaries are hosted, the software repository key, and to install PowerShell Core per the recommended methodology as defined in the PowerShell Core Install Guide.
        • apt: The default package management tool for Ubuntu.
          • sources: Software repositories to add.
            • sourceline: The software repository configuration.
            • key_url: The public key for encrypting the traffic.
          • packages: Software packages to install
            • powershell: Install PowerShell Core on Linux, please and thank you.
      • osx_image: The macOS image that you want to use.
        • As of 20171125, the Travis CI default is 7.3, which is an older macOS 10.11 image.
        • The official PowerShell install guide only lists support for macOS 10.12; however, I have performed a few basic functional tests on osx images: 7.3 (10.11) & 6.4 (10.10). PowerShell Core installed, and completed the build and test runs successfully without any additional configuration on macOS 10.11, but failed on macOS 10.10.
          • PowerShell Core may work on macOS 10.10 with additional configuration, but I am not interested in researching this any further at this time.
        • If you are concerned about breaking changes between macOS versions, you can duplicate the osx matrix image section and replace the value of osx_image with a different version.
          • Available image versions can be found here.
      • before_install: This matrix image section overrides the global before_install configuration for our osx image, and is used for installing PowerShell Core as defined in the installation guide.
        • brew tap caskroom/cask: reference

          Homebrew-Cask extends Homebrew and brings its elegance, simplicity, and speed to macOS applications and large binaries alike.

        • brew cask install powershell: Install PowerShell Core on macOS, please and thank you.
    • fast_finish: Job failures halt the build.  If you would rather have the build attempt to continue on error, change the value to false.
  • install: This section can be used for calling the PowerShell script to install dependencies, such as any modules needed to build and/or test the script.
    • I highly recommend storing the logic for each section in a separate file so that:
      1. It is easier for you to reuse & maintain code if you choose to also integrate with AppVeyor for testing your open-source project for free on Windows PowerShell as well, and also…
      2. …because of the inherent challenges with embedding code in code.
    • The build lifecycle order of operations has the install section follow the before_install section and precedes the before_script section.
    • Here is my install-dependencies.ps1 script for the ArmorPowerShell project.
  • before_script: This section can be used for calling your PowerShell build script to do things such as update the module manifest, update the documentation, et cetera.
    • Here is my build.ps1 script for the ArmorPowerShell project.
  • script: This section can be used for calling your PowerShell unit, integration, and/or functional test scripts.
    • If you are new to these concepts, I recommend reading up on those topics, as well as Pester.
    • Here is my start-tests.ps1 script for the ArmorPowerShell project.
  • after_success: This section can be used for calling a deployment script if that makes sense for your project, such as publishing your module, script, et cetera to the PowerShell Gallery, NuGet, Chocolatey, GitHub Releases, et cetera.

Travis CI is an extremely powerful platform with tons of other features that you can take advantage of, but that is all that I am going to cover in this post as to the possibilities available in the .travis.yml config file.

Lint your .travis.yml config file

Now, it’s time to test your config file using the Travis Client that we installed earlier by running travis lint.

> travis lint
Warnings for .travis.yml:
[x] in matrix.include section: unexpected key osx_image, dropping
[x] in matrix.include section: unexpected key dist, dropping
[x] in matrix.include section: unexpected key sudo, dropping

Wait, what?  Why am I seeing these warnings?

As of 20171125, this type of build matrix image configuration is recommended per the Travis CI multiple operating system build configurations documentation, but it will generate three false positive unexpected key warnings when linting (validating) your .travis.yml config file.  These three warnings can be disregarded and have been reported here.  Any warnings or errors other than these should be addressed.

Commit your .travis.yml config file

When you are ready, run the following commands to:

  1. Stage the ./travis.yml config file to the index
  2. Commit the ./travis.yml config file
  3. And then push it up to the master branch of your GitHub public repo, which will trigger the first Travis CI build for your project!
    1. If you prefer to push the change to a branch other than master, then update the branch name accordingly.
git add ./.travis.yml
git commit --message 'Initial commit' ./.travis.yml
git push origin master

Protect your important branches

Now that you have configured and run your first build, update your GitHub repository settings so that any contributions to your project must first pass your build and testing framework as a prerequisite for consideration.  To do so:

Screenshot from 2017-11-25 11-32-00

You made it!

Voila!  You’re done!  There are plenty of other things that you can do here such as configure notifications so that Travis CI automatically posts your build results in a Slack channel, publish your PowerShell module on successful build to the PowerShell gallery, or add a badge to your indicating whether the last build passed or failed, all of which I’ll cover in the next post, but you should have enough now to start testing your PowerShell project on macOS and Ubuntu for free on the powerful & versatile Travis CI platform.  Enjoy!

VCAP6-DCV Deploy Study Sheet

I recently came across Chris Wahl’s VCAP5 study sheets while looking for learning material for the VMware Certified Advanced Professional 6.0 – Data Center Virtualization Deployment (VCAP6-DCV Deploy) exam, and I really liked how it presented the blueprint in an easily consumable, goal-oriented format, so I decided to generate one for this exam.  In the same spirit, I am sharing this (and any others that I create later on) freely from my Study Sheets page.  Enjoy!