A build matrix is made up by several multiple jobs that run in parallel.
This can be useful in many cases, but the two primary reasons to use a build matrix are:
- Reducing the overall build execution time
- Running tests against different versions of runtimes or dependencies
The examples on this page focus on the latter use case.
There are two ways to define a matrix in the
- Using the Matrix Expansion feature
- Listing individual job configs
Both features can be combined.
Matrix Expansion #
Certain keys are defined as matrix expansion keys that take arrays of values, creating an additional job per value. If several matrix expansion keys are given, this multiplies the number of jobs created.
For example, the following configuration produces a build matrix that expands
to 8 individual (2 * 2 * 2) jobs, combining each value from the three
matrix expansion keys
rvm: - 2.5 - 2.2 gemfile: - gemfiles/Gemfile.rails-3.2.x - gemfiles/Gemfile.rails-3.0.x env: - ISOLATED=true - ISOLATED=false
Listing individual jobs #
In addition, jobs can be specified by adding entries to the key
For example, if not all of those combinations of the matrix expansion above are relevant, jobs can be specified individually like so:
jobs: include: - rvm: 2.5 gemfile: gemfiles/Gemfile.rails-3.2.x env: ISOLATED=false - rvm: 2.2 gemfile: gemfiles/Gemfile.rails-3.0.x env: ISOLATED=true
Build matrixes are currently limited to a maximum of 200 jobs for both private and public repositories. If you are on an open-source plan, please remember that Travis CI provides this service free of charge to the community. So please only specify the matrix you actually need.
Excluding Jobs #
The build matrix expansion sometimes produced unwanted combinations. In that
case it can be convenient to exclude certain combinations using the key
jobs.exclude, instead of listing all jobs individually.
For example, this would exclude two jobs from the build matrix:
jobs: exclude: - rvm: 1.9.3 gemfile: gemfiles/Gemfile.rails-2.3.x env: ISOLATED=true - rvm: jruby gemfile: gemfiles/Gemfile.rails-2.3.x env: ISOLATED=true
If the jobs you want to exclude from the build matrix share the same matrix parameters, you can specify only those and omit the varying parts.
Suppose you have:
language: ruby rvm: - 1.9.3 - 2.0.0 - 2.1.0 env: - DB=mongodb - DB=redis - DB=mysql gemfile: - Gemfile - gemfiles/rails4.gemfile - gemfiles/rails31.gemfile - gemfiles/rails32.gemfile
This results in a 3×3×4 build matrix. To exclude all jobs which have
Gemfile, you can write:
jobs: exclude: - rvm: 2.0.0 gemfile: Gemfile
Which is equivalent to:
jobs: exclude: - rvm: 2.0.0 gemfile: Gemfile env: DB=mongodb - rvm: 2.0.0 gemfile: Gemfile env: DB=redis - rvm: 2.0.0 gemfile: Gemfile env: DB=mysql
Excluding jobs with
env value #
When excluding jobs with
env values, the value must match
language: ruby rvm: - 1.9.3 - 2.0.0 - 2.1.0 env: - DB=mongodb SUITE=all - DB=mongodb SUITE=compact - DB=redis - DB=mysql jobs: exclude: - rvm: 1.9.3 env: DB=mongodb
defines a 3×4 matrix, because the
env value does not match with
any job defined in the matrix.
To exclude all Ruby 1.9.3 jobs with
DB=mongodb set, write:
language: ruby rvm: - 1.9.3 - 2.0.0 - 2.1.0 env: - DB=mongodb SUITE=all - DB=mongodb SUITE=compact - DB=redis - DB=mysql jobs: exclude: - rvm: 1.9.3 env: DB=mongodb SUITE=all # not 'env: DB=mongodb' or 'env: SUITE=all DB=mongodb' - rvm: 1.9.3 env: DB=mongodb SUITE=compact # not 'env: SUITE=compact DB=mongodb'
Explicitly Including Jobs #
It is also possible to include entries into the matrix with
jobs: include: - rvm: ruby-head gemfile: gemfiles/Gemfile.rails-3.2.x env: ISOLATED=false
This adds a particular job to the build matrix which has already been populated.
This is useful if you want to only test the latest version of a dependency together with the latest version of the runtime.
You can use this method to create a build matrix containing only specific combinations. For example,
language: python jobs: include: - python: "2.7" env: TEST_SUITE=suite_2_7 - python: "3.8" env: TEST_SUITE=suite_3_8 - python: "pypy" env: TEST_SUITE=suite_pypy script: ./test.py $TEST_SUITE
creates a build matrix with 3 jobs, which runs test suite for each version of Python.
Explicitly included jobs inherit the first value in the array #
The jobs which are explicitly included inherit the first value of the expansion keys defined.
In this example with a 3-job Python build matrix, each job in
python value set to
You can explicitly set the python version for a specific entry:
language: python python: - '3.8' - '3.7' - '2.7' jobs: include: - python: '3.8' # this is not strictly necessary env: EXTRA_TESTS=true - python: '3.7' env: EXTRA_TESTS=true script: env $EXTRA_TESTS ./test.py $TEST_SUITE
Explicitly included jobs with only one element in the build matrix #
As a special case, if your build matrix has only one element and you have explicitly included jobs, matrix expansion is not done and the explicit jobs completely define your build. For example:
language: python python: - '3.8' jobs: include: - env: EXTRA_TESTS=true # only defines one job with `python: 3.8` and `env: EXTRA_TESTS=true`
If you need the (sole) job from the matrix in such a case, too, add a blank job entry to the explicit list (as it would inherit all values from the matrix with no changes):
language: python python: - '3.8' jobs: include: - - env: EXTRA_TESTS=true # defines two jobs: # - python: 3.8 # - python: 3.8 # env: EXTRA_TESTS=true
Rows that are Allowed to Fail #
You can define rows that are allowed to fail in the build matrix. Allowed failures are items in your build matrix that are allowed to fail without causing the entire build to fail. This lets you add in experimental and preparatory builds to test against versions or configurations that you are not ready to officially support.
Define allowed failures in the build matrix as key/value pairs:
jobs: allow_failures: - rvm: 1.9.3
Matching Jobs with
When matching jobs against the definitions given in
allow_failures must be met exactly, and
all the keys in
allow_failures element must exist in the
top level of the build matrix (i.e., not in
allow_failures Examples #
language: ruby rvm: - 2.0.0 - 2.1.6 env: global: - SECRET_VAR1=SECRET1 jobs: - SECRET_VAR2=SECRET2 jobs: allow_failures: - env: SECRET_VAR1=SECRET1 SECRET_VAR2=SECRET2
Here, no job is allowed to fail because no job has the
language: php php: - 5.6 - 7.0 jobs: include: - php: 7.0 env: KEY=VALUE allow_failures: - php: 7.0 env: KEY=VALUE
Without the top-level
env, no job will be allowed to fail.
Fast Finishing #
If some rows in the build matrix are allowed to fail, the build won’t be marked as finished until they have completed.
To mark the build as finished as soon as possible, add
fast_finish: true to the
jobs section of your
.travis.yml like this:
jobs: fast_finish: true
Now, the build result will be determined as soon as all the required jobs finish, based on these results, while the rest of the
allow_failures jobs continue to run.
Using Different Programming Languages per Job #
You can also use the
jobs.include feature to have different languages for each job in your build. For example,
dist: xenial language: php php: - '5.6' jobs: include: - language: python python: 3.8 script: - python -c "print('Hi from Python!')" - language: node_js node_js: 12 script: - node -e "console.log('Hi from NodeJS!')" - language: java jdk: openjdk8 script: - javac -help
This creates a build with 3 jobs as follows:
- A Python 3.8 job
- A Node.js 12 job
- A Java OpenJDK 8 job
Job Names #
Jobs listed in
jobs.include can be named by using the key
name, like so:
jobs: include: - name: Job 1 script: echo "Running job 1"
This name will appear on the build matrix UI and can be convenient in order to quickly identify jobs in a large matrix.
Jobs generated through the Matrix Expansion feature cannot be named.
Job Uniqueness and Duplicate Jobs #
Jobs need to be unique, and duplicate jobs are dropped during the Build Config Validation process.
For example, this config would result in only one job using the YAML anchors and aliases:
_shared_job: &shared_job script: echo "shared script config" jobs: include: - <<: *shared_job - <<: *shared_job
In rare circumstances it can still be desirable to execute multiple jobs with the same config. In such cases, job uniqueness can be achieved by specifying any additional key, e.g. a job name:
_shared_job: &shared_job script: echo "shared script config" jobs: include: - name: Job 1 <<: *shared_job - name: Job 2 <<: *shared_job