Writing Tasks
A task defines a sequence of instructions to execute and an execution environment
to execute these instructions in. Let's see a line-by-line example of a .cirrus.yml configuration file first:
The example above defines a single task that will be scheduled and executed on the Linux Community Cluster using the openjdk:latest Docker image.
Only one user-defined script instruction to run ./gradlew test will be executed. Not that complex, right?
Please read the topics below if you want better understand what's going on in a more complex .cirrus.yml configuration file, such as this:
task:
container:
image: node:latest # (1)
node_modules_cache: # (2)
folder: node_modules
fingerprint_script: cat yarn.lock
populate_script: yarn install
matrix: # (3)
- name: Lint
skip: !changesInclude('.cirrus.yml', '**.{js,ts}') # (4)
lint_script: yarn run lint
- name: Test
container:
matrix: # (5)
- image: node:latest
- image: node:lts
test_script: yarn run test
- name: Publish
depends_on:
- Lint
- Test
only_if: $BRANCH == "master" # (6)
publish_script: yarn run publish
- Use any Docker image from public or private registries
- Use cache instruction to persist folders based on an arbitrary
fingerprint_script. - Use
matrixmodification to produce many similar tasks. - See what kind of files were changes and skip tasks that are not applicable.
See
changesIncludeandchangesIncludeOnlydocumentation for details. - Use nested
matrixmodification to produce even more tasks. - Completely exclude tasks from execution graph by any custom condition.
task:
arm_container:
image: node:latest # (1)
node_modules_cache: # (2)
folder: node_modules
fingerprint_script: cat yarn.lock
populate_script: yarn install
matrix: # (3)
- name: Lint
skip: !changesInclude('.cirrus.yml', '**.{js,ts}') # (4)
lint_script: yarn run lint
- name: Test
arm_container:
matrix: # (5)
- image: node:latest
- image: node:lts
test_script: yarn run test
- name: Publish
depends_on:
- Lint
- Test
only_if: $BRANCH == "master" # (6)
publish_script: yarn run publish
- Use any Docker image from public or private registries
- Use cache instruction to persist folders based on an arbitrary
fingerprint_script. - Use
matrixmodification to produce many similar tasks. - See what kind of files were changes and skip tasks that are not applicable.
See
changesIncludeandchangesIncludeOnlydocumentation for details. - Use nested
matrixmodification to produce even more tasks. - Completely exclude tasks from execution graph by any custom condition.
Task Naming
To name a task one can use the name field. foo_task syntax is a syntactic sugar. Separate name
field is very useful when you want to have a rich task name:
Note: instructions within a task can only be named via a prefix (e.g. test_script).
Visual Task Creation for Beginners
If you are just getting started and prefer a more visual way of creating tasks, there is a third-party Cirrus CI Configuration Builder for generating YAML config that might be helpful.
Execution Environment¶
In order to specify where to execute a particular task you can choose from a variety of options by defining one of the
following fields for a task:
| Field Name | Managed by | Description |
|---|---|---|
container |
us | Linux Docker Container |
arm_container |
us | Linux Arm Docker Container |
windows_container |
us | Windows Docker Container |
macos_instance |
us | macOS Virtual Machines |
freebsd_instance |
us | FreeBSD Virtual Machines |
compute_engine_instance |
us | Full-fledged custom VM |
persistent_worker |
you | Use any host on any platform and architecture |
gce_instance |
you | Linux, Windows and FreeBSD Virtual Machines in your GCP project |
gke_container |
you | Linux Docker Containers on private GKE cluster |
ec2_instance |
you | Linux Virtual Machines in your AWS |
eks_instance |
you | Linux Docker Containers on private EKS cluster |
azure_container_instance |
you | Linux and Windows Docker Container on Azure |
oke_instance |
you | Linux x86 and Arm Containers on Oracle Cloud |
Supported Instructions¶
Each task is essentially a collection of instructions that are executed sequentially. The following instructions are supported:
scriptinstruction to execute a script.background_scriptinstruction to execute a script in a background.cacheinstruction to persist files between task runs.artifactsinstruction to store and expose files created via a task.fileinstruction to create a file from an environment variable.
Script Instruction¶
A script instruction executes commands via shell on Unix or batch on Windows. A script instruction can be named by
adding a name as a prefix. For example test_script or my_very_specific_build_step_script. Naming script instructions
helps gather more granular information about task execution. Cirrus CI will use it in future to auto-detect performance
regressions.
Script commands can be specified as a single string value or a list of string values in a .cirrus.yml configuration file
like in the example below:
check_task:
compile_script: gradle --parallel classes testClasses
check_script:
- echo "Here comes more than one script!"
- printenv
- gradle check
Note: Each script instruction is executed in a newly created process, therefore environment variables are not preserved between them.
Execution on Windows
When executed on Windows via batch, Cirrus Agent will wrap each line of the script in a call so it's possible to
fail fast upon first line exiting with non-zero exit code.
To avoid this "syntactic sugar" just create a script file and execute it.
Background Script Instruction¶
A background_script instruction is absolutely the same as script instruction but Cirrus CI won't wait for the script to finish
and will continue execution of further instructions.
Background scripts can be useful when something needs to be executed in the background. For example, a database or
some emulators. Traditionally the same effect is achieved by adding & to a command like $: command &. Problem here
is that logs from command will be mixed into regular logs of the following commands. By using background scripts
not only logs will be properly saved and displayed, but also command itself will be properly killed in the end of a task.
Here is an example of how background_script instruction can be used to run an android emulator:
android_test_task:
start_emulator_background_script: emulator -avd test -no-audio -no-window
wait_for_emulator_to_boot_script: adb wait-for-device
test_script: gradle test
Cache Instruction¶
A cache instruction allows to persist a folder and reuse it during the next execution of the task. A cache instruction can be named the same way as script instruction.
Here is an example:
Either folder or a folders field (with a list of folder paths) is required and they tell the agent which folder paths to cache.
Folder paths should be generally relative to the working directory (e.g. node_modules), with the exception of when only a single folder specified. In this case, it can be also an absolute path (/usr/local/bundle).
Folder paths can contain a "glob" pattern to cache multiple files/folders within a working directory (e.g. **/node_modules will cache every node_modules folder within the working directory).
A fingerprint_script and fingerprint_key are optional fields that can specify either:
- a script, the output of which will be hashed and used as a key for the given cache:
- a final cache key:
These two fields are mutually exclusive. By default the task name is used as a fingerprint value.
After the last script instruction for the task succeeds, Cirrus CI will calculate checksum of the cached folder (note that it's unrelated to fingerprint_script or fingerprint_key fields) and re-upload the cache if it finds any changes.
To avoid a time-costly re-upload, remove volatile files from the cache (for example, in the last script instruction of a task).
populate_script is an optional field that can specify a script that will be executed to populate the cache.
populate_script should create the folder if it doesn't exist before the cache instruction.
If your dependencies are updated often, please pay attention to fingerprint_script and make sure it will produce different outputs for different versions of your dependency (ideally just print locked versions of dependencies).
reupload_on_changes is an optional field that can specify whether Cirrus Agent should check if
contents of cached folder have changed during task execution and re-upload a cache entry in case of any changes.
If reupload_on_changes option is not set explicitly then it will be set to false if fingerprint_script or fingerprint_key is presented and true otherwise.
Cirrus Agent will detect additions, deletions and modifications of any files under specified folder. All of the detected changes will be
logged under Upload '$CACHE_NAME' cache instructions for easier debugging of cache invalidations.
That means the only difference between the example above and below is that yarn install will always be executed in the
example below where in the example above only when yarn.lock has changes.
Caching for Pull Requests
Tasks for PRs upload caches to a separate caching namespace to not interfere with caches used by other tasks. But such PR tasks can read all caches even from the main caching namespace for a repository.
Scope of cached artifacts
Cache artifacts are shared between tasks, so two caches with the same name on e.g. Linux containers and macOS VMs will share the same set of files.
This may introduce binary incompatibility between caches. To avoid that, add echo $CIRRUS_OS into fingerprint_script or use $CIRRUS_OS in fingerprint_key, which will distinguish caches based on OS.
Manual cache upload¶
Normally caches are uploaded at the end of the task execution. However, you can override the default behavior and upload them earlier.
To do this, use the upload_caches instruction, which uploads a list of caches passed to it once executed:
Note that pip cache won't be uploaded in this example: using upload_caches disables the default behavior where all caches are automatically uploaded at the end of the task, so if you want to upload pip cache too, you'll have to either:
- extend the list of uploaded caches in the first
upload_cachesinstruction - insert a second
upload_cachesinstruction that specifically targetspipcache
Artifacts Instruction¶
An artifacts instruction allows to store files and expose them in the UI for downloading later. An artifacts instruction
can be named the same way as script instruction and has only one required path field which accepts a glob pattern
of files relative to $CIRRUS_WORKING_DIR to store. Right now only storing files under $CIRRUS_WORKING_DIR folder as artifacts is supported with a total size limit of 1G for a community task and with no limit on your own infrastructure.
In the example below, Build and Test task produces two artifacts: binaries artifacts with all executables built during a
successful task completion and junit artifacts with all test reports regardless of the final task status (more about
that you can learn in the next section describing execution behavior).
build_and_test_task:
# instructions to build and test
binaries_artifacts:
path: "build/*"
always:
junit_artifacts:
path: "**/test-results/**.xml"
format: junit
URLs to the artifacts
Latest build artifacts¶
It is possible to refer to the latest artifacts directly (artifacts of the latest successful build). Use the following link format to download the latest artifact of a particular task:
https://api.cirrus-ci.com/v1/artifact/github/<USER OR ORGANIZATION>/<REPOSITORY>/<TASK NAME OR ALIAS>/<ARTIFACTS_NAME>/<PATH>
It is possible to also download an archive of all files within an artifact with the following link:
https://api.cirrus-ci.com/v1/artifact/github/<USER OR ORGANIZATION>/<REPOSITORY>/<TASK NAME OR ALIAS>/<ARTIFACTS_NAME>.zip
By default, Cirrus looks up the latest successful build of the default branch for the repository but the branch name
can be customized via ?branch=<BRANCH> query parameter.
Current build artifacts¶
It is possible to refer to the artifacts of the current build directly:
Note that if several tasks are uploading artifacts with the same name then the ZIP archive from the above link will contain merged content of all artifacts. It's also possible to refer to an artifact of a particular task within a build by name:
https://api.cirrus-ci.com/v1/artifact/build/<CIRRUS_BUILD_ID>/<TASK NAME OR ALIAS>/<ARTIFACTS_NAME>.zip
It is also possible to download artifacts given a task id directly:
It's also possible to download a particular file of an artifact and not the whole archive by using <ARTIFACTS_NAME>/<PATH>
instead of <ARTIFACTS_NAME>.zip.
Artifact Type¶
By default, Cirrus CI will try to guess mimetype of files in artifacts by looking at their extensions. In case when artifacts
don't have extensions, it's possible to explicitly set the Content-Type via type field:
A list of some of the basic types supported can be found here.
Artifact Parsing¶
Cirrus CI supports parsing artifacts in order to extract information that can be presented in the UI for a better user experience.
Use the format field of an artifact instruction to specify artifact's format (mimetypes):
Currently, Cirrus CI supports:
- Android Lint Report format
- GolangCI Lint's JSON format
- JUnit's XML format
- XCLogParser
- JetBrains Qodana
- Buf CLI for Protocol Buffers
Please let us know what kind of formats Cirrus CI should support next!
File Instruction¶
A file instruction allows to create a file from an environment variable. It is especially useful for situations when
execution environment doesn't have proper shell to use echo ... >> ... syntax, for example, within scratch Docker containers.
Here is an example of how to populate Docker config from an encrypted environment variable:
task:
environment:
DOCKER_CONFIG: ENCRYPTED[qwerty]
docker_config_file:
path: /root/.docker/config
variable_name: DOCKER_CONFIG
Execution Behavior of Instructions¶
By default Cirrus CI executes instructions one after another and stops the overall task execution on the first failure.
Sometimes there might be situations when some scripts should always be executed or some debug information needs to be saved
on a failure. For such situations the always and on_failure keywords can be used to group instructions.
task:
test_script: ./run_tests.sh
on_failure:
debug_script: ./print_additional_debug_info.sh
always:
test_reports_script: ./print_test_reports.sh
In the example above, print_additional_debug_info.sh script will be executed only on failures to output some additional
debug information. print_test_reports.sh on the other hand will be executed both on successful and and failed runs to
print test reports (test reports are always useful! 
).
Environment Variables¶
Environment variables can be configured under the env or environment keywords in .cirrus.yml files. Here is an example:
You can reference other environment variables using $VAR, ${VAR} or %VAR% syntax:
custom_path_task:
env:
SDK_ROOT: ${HOME}/sdk
PATH: ${SDK_ROOT}/bin:${PATH}
custom_script: sdktool install
Environment variables may also be set at the root level of .cirrus.yml. In that case, they will be merged with each task's
individual environment variables, but the task level variables always take precedence. For example:
Will output /opt/bin:/usr/local/bin:/usr/bin or similar, but will not include /sdk/bin because this root level setting is
ignored.
Also some default environment variables are pre-defined:
| Name | Value / Description |
|---|---|
| CI | true |
| CIRRUS_CI | true |
| CI_NODE_INDEX | Index of the current task within CI_NODE_TOTAL tasks |
| CI_NODE_TOTAL | Total amount of unique tasks for a given CIRRUS_BUILD_ID build |
| CONTINUOUS_INTEGRATION | true |
| CIRRUS_API_CREATED | true if the current build was created through the API. |
| CIRRUS_BASE_BRANCH | Base branch name if current build was triggered by a PR. For example master |
| CIRRUS_BASE_SHA | Base SHA if current build was triggered by a PR |
| CIRRUS_BRANCH | Branch name. For example my-feature |
| CIRRUS_BUILD_ID | Unique build ID |
| CIRRUS_CHANGE_IN_REPO | Git SHA |
| CIRRUS_CHANGE_MESSAGE | Commit message or PR title and description, depending on trigger event (Non-PRs or PRs respectively). |
| CIRRUS_CHANGE_TITLE | First line of CIRRUS_CHANGE_MESSAGE |
| CIRRUS_CRON | Cron Build name configured in the repository settings if this build was triggered by Cron. For example, nightly. |
| CIRRUS_DEFAULT_BRANCH | Default repository branch name. For example master |
| CIRRUS_DOCKER_CONTEXT | Docker build's context directory to use for Dockerfile as a CI environment. Defaults to project's root directory. |
| CIRRUS_LAST_GREEN_BUILD_ID | The build id of the last successful build on the same branch at the time of the current build creation. |
| CIRRUS_LAST_GREEN_CHANGE | Corresponding to CIRRUS_LAST_GREEN_BUILD_ID SHA (used in changesInclude and changesIncludeOnly functions). |
| CIRRUS_PR | PR number if current build was triggered by a PR. For example 239. |
| CIRRUS_PR_DRAFT | true if current build was triggered by a Draft PR. |
| CIRRUS_PR_LABELS | comma separated list of PR's labels if current build was triggered by a PR. |
| CIRRUS_TAG | Tag name if current build was triggered by a new tag. For example v1.0 |
| CIRRUS_OIDC_TOKEN | OpenID Token issued by https://oidc.cirrus-ci.com with audience set to https://cirrus-ci.com/github/$CIRRUS_REPO_OWNER (can be changed via $CIRRUS_OIDC_TOKEN_AUDIENCE). Please refer to Cirrus CI OpenID Configuration for the set of all supported claims. |
| CIRRUS_OS, OS | Host OS. Either linux, windows or darwin. |
| CIRRUS_TASK_NAME | Task name |
| CIRRUS_TASK_ID | Unique task ID |
| CIRRUS_RELEASE | GitHub Release id if current tag was created for a release. Handy for uploading release assets. |
| CIRRUS_REPO_CLONE_TOKEN | Temporary GitHub access token to perform a clone. |
| CIRRUS_REPO_NAME | Repository name. For example my-project |
| CIRRUS_REPO_OWNER | Repository owner (an organization or a user). For example my-organization |
| CIRRUS_REPO_FULL_NAME | Repository full name/slug. For example my-organization/my-project |
| CIRRUS_REPO_CLONE_URL | URL used for cloning. For example https://github.com/my-organization/my-project.git |
| CIRRUS_USER_COLLABORATOR | true if a user initialized a build is already a contributor to the repository. false otherwise. |
| CIRRUS_USER_PERMISSION | admin, write, read or none. |
| CIRRUS_HTTP_CACHE_HOST | Host and port number on which local HTTP cache can be accessed on. |
| GITHUB_CHECK_SUITE_ID | Monotonically increasing id of a corresponding GitHub Check Suite which caused the Cirrus CI build. |
| CIRRUS_ENV | Path to a file, by writing to which you can set task-wide environment variables. |
| CIRRUS_ENV_SENSITIVE | Set to true to mask all variable values written to the CIRRUS_ENV file in the console output |
Behavioral Environment Variables¶
And some environment variables can be set to control behavior of the Cirrus CI Agent:
| Name | Default Value | Description |
|---|---|---|
| CIRRUS_CLONE_DEPTH | 0 which will reflect in a full clone of a single branch |
Clone depth. |
| CIRRUS_CLONE_SUBMODULES | false |
Set to true to clone submodules recursively. |
| CIRRUS_LOG_TIMESTAMP | false |
Indicate Cirrus Agent to prepend timestamp to each line of logs. |
| CIRRUS_OIDC_TOKEN_AUDIENCE | not set | Allows to override aud claim for CIRRUS_OIDC_TOKEN. |
| CIRRUS_SHELL | sh on Linux/macOS/FreeBSD and cmd.exe on Windows. Set to direct to execute each script directly without wrapping the commands in a shell script. |
Shell that Cirrus CI uses to execute scripts. By default sh is used. |
| CIRRUS_VOLUME | /tmp |
Defines a path for a temporary volume to be mounted into instances running in a Kubernetes cluster. This volume is mounted into all additional containers and is persisted between steps of a pipe. |
| CIRRUS_WORKING_DIR | cirrus-ci-build folder inside of a system's temporary folder |
Working directory where Cirrus CI executes builds. Default to cirrus-ci-build folder inside of a system's temporary folder. |
| CIRRUS_ESCAPING_PROCESSES | not set | Set this variable to prevent the agent from terminating the processes spawned in each non-background instruction after that instruction ends. By default, the agent tries it's best to garbage collect these processes and their standard input/output streams. It's generally better to use a Background Script Instruction instead of this variable to achieve the same effect. |
| CIRRUS_WINDOWS_ERROR_MODE | not set | Set this value to force all processes spawned by the agent to call the equivalent of SetErrorMode() with the provided value (for example, 0x8001) before beginning their execution. |
| CIRRUS_VAULT_URL | not set | Address of the Vault server expressed as a URL and port (for example, https://vault.example.com:8200/), see HashiCorp Vault Support. |
| CIRRUS_VAULT_NAMESPACE | not set | A Vault Enterprise Namespace to use when authenticating and reading secrets from Vault. |
| CIRRUS_VAULT_AUTH_PATH | jwt |
Alternative auth method mount point, in case it was mounted to a non-default path. |
| CIRRUS_VAULT_ROLE | not set | Auth method-specific role to use (see JWT/OIDC Auth Method, for example). |
Encrypted Variables¶
It is possible to add encrypted variables to a .cirrus.yml file. These variables are decrypted only in builds for commits and pull requests that are made by users with write permission or approved by them.
In order to encrypt a variable go to repository's settings page via clicking settings icon 
on a repository's main page (for example https://cirrus-ci.com/github/my-organization/my-repository) and follow instructions.
Warning
Only users with WRITE permissions can add encrypted variables to a repository.
An encrypted variable will be presented in a form like ENCRYPTED[qwerty239abc] which can be safely committed to .cirrus.yml file:
Cirrus CI encrypts variables with a unique per repository 256-bit encryption key so forks and even repositories within
the same organization cannot re-use them. qwerty239abc from the example above is NOT the content of your encrypted
variable, it's just an internal ID. No one can brute force your secrets from such ID. In addition, Cirrus CI doesn't know
a relation between an encrypted variable and a repository for which the encrypted variable was created.
Organization Level Encrypted Variables
Sometimes there might be secrets that are used in almost all repositories of an organization. For example, credentials
to a compute service where tasks will be executed. In order to create such sharable
encrypted variable go to organization's settings page via clicking settings icon
on an organization's main page (for example https://cirrus-ci.com/github/my-organization) and follow instructions
in Organization Level Encrypted Variables section.
Encrypted Variable for Cloud Credentials
In case you use integration with one of supported computing services, an encrypted variable used to store credentials that Cirrus is using to communicate with the computing service won't be decrypted if used in environment variables. These credentials have too many permissions for most of the cases, please create separate credentials with the minimum needed permissions for your specific case.
Skipping Task in Forked Repository
In forked repository the decryption of variable fails, which causes failure of task depending on it. To avoid this by default, make the sensitive task conditional:
Owner of forked repository can re-enable the task, if they have the required sensitive data, by encrypting
the variable by themselves and editing both the encrypted variable and repo-owner condition
in the .cirrus.yml file.
HashiCorp Vault support¶
In addition to using Cirrus CI for managing secrets, it is possible to retrieve secrets from HashiCorp Vault.
You will need to configure a JWT authentication method and point it to the Cirrus CI's OIDC discovery URL: https://oidc.cirrus-ci.com.
This ensures that a cryptographic JWT token (CIRRUS_OIDC_TOKEN) that each Cirrus CI's task get assigned will be verified by your Vault installation.
From the Cirrus CI's side, use the CIRRUS_VAULT_URL environment variable to point Cirrus Agent at your vault and configure other Vault-specific variables, if needed. Note that it's not required for CIRRUS_VAULT_URL to be publicly available since Cirrus CI can orchestrate tasks on your infrastructure. Only Cirrus Agent executing a task from within an execution environment needs access to your Vault.
Once done, you will be able to use the VAULT[path/to/secret selector] syntax to retrieve a version 2 secret, for example:
The path is exactly the one you are familiar from invoking Vault CLI like vault read ..., and the selector is a simply dot-delimited list of fields to query in the output.
Cron Builds¶
It is possible to configure invocations of re-occurring builds via the well-known Cron expressions. Cron builds can be
configured on a repository's settings page (not in .cirrus.yml).
It's possible to configure several cron builds with unique names which will be available via CIRRUS_CRON environment variable.
Each cron build should specify branch to trigger new builds for and a cron expression compatible with Quartz. You can use
this generator to generate/validate your expressions.
Note: Cron Builds are timed with the UTC timezone.
Matrix Modification¶
Sometimes it's useful to run the same task against different software versions. Or run different batches of tests based
on an environment variable. For cases like these, the matrix modifier comes very handy. It's possible to use matrix
keyword only inside of a particular task to have multiple tasks based on the original one. Each new task will be created
from the original task by replacing the whole matrix YAML node with each matrix's children separately.
Let check an example of a .cirrus.yml:
Which will be expanded into:
Tip
The matrix modifier can be used multiple times within a task.
The matrix modification makes it easy to create some pretty complex testing scenarios like this:
Task Execution Dependencies¶
Sometimes it might be very handy to execute some tasks only after successful execution of other tasks. For such cases
it is possible to specify task names that a particular task depends. Use depends_on keyword to define dependencies:
Task Names and Aliases
It is possible to specify the task's name via the name field. lint_task syntax is a syntactic sugar that will be
expanded into:
Names can be also pretty complex:
task:
name: Test Shard $TESTS_SPLIT
env:
matrix:
TESTS_SPLIT: 1/3
TESTS_SPLIT: 2/2
TESTS_SPLIT: 3/3
tests_script: ./.ci/tests.sh
deploy_task:
only_if: $CIRRUS_BRANCH == 'master'
depends_on:
- Test Shard 1/3
- Test Shard 2/3
- Test Shard 3/3
script: ./.ci/deploy.sh
...
Complex task names make it difficult to list and maintain all of such task names in your depends_on field. In order to
make it simpler you can use the alias field to have a short simplified name for several tasks to use in depends_on.
Here is a modified version of an example above that leverages the alias field:
Conditional Task Execution¶
Some tasks are meant to be created only if a certain condition is met. And some tasks can be skipped in some cases.
Cirrus CI supports the only_if and skip keywords in order to provide such flexibility:
-
The
only_ifkeyword controls whether or not a task will be created. For example, you may want to publish only changes committed to themasterbranch. -
The
skipkeyword allows to skip execution of a task and mark it as successful. For example, you may want to skip linting if no source files have changed since the last successful run.
Skip CI Completely
Just include [skip ci] or [skip cirrus] in the first line or last line of your commit message in order to skip CI execution for a commit completely.
If you push multiple commits at the same time, only the last commit message will be checked for [skip ci] or [ci skip].
If you open a PR, PR title will be checked for [skip ci] or [ci skip] instead of the last commit message on the PR branch.
Supported Operators¶
Currently only basic operators like ==, !=, =~, !=~, &&, || and unary ! are supported in only_if and skip expressions.
Environment variables can also be used as usually.
Pattern Matching Example
Use =~ operator for pattern matching.
Note that =~ operator can match against multiline values (dotall mode) and therefore looking for the exact occurrence of the regular expression
so don't forget to use .* around your term for matching it at any position (for example, $CIRRUS_CHANGE_TITLE =~ '.*[docs].*').
Supported Functions¶
Currently two functions are supported in the only_if and skip expressions:
changesIncludefunction allows to check which files were changedchangesIncludeOnlyis a more strict version ofchangesInclude, i.e. it won't evaluate totrueif there are changed files other than the ones covered by patterns
These two functions behave differently for PR builds and regular builds:
- For PR builds, functions check the list of files affected by the PR.
- For regular builds, the
CIRRUS_LAST_GREEN_CHANGEenvironment variable will be used to determine list of affected files betweenCIRRUS_LAST_GREEN_CHANGEandCIRRUS_CHANGE_IN_REPO. In caseCIRRUS_LAST_GREEN_CHANGEis not available (either it's a new branch or there were no passing builds before), list of files affected by a commit associated withCIRRUS_CHANGE_IN_REPOenvironment variable will be used instead.
changesInclude function can be very useful for skipping some tasks when no changes to sources have been made since the
last successful Cirrus CI build.
changesIncludeOnly function can be used to skip running a heavyweight task if only documentation was changed, for example:
Auto-Cancellation of Tasks¶
Cirrus CI can automatically cancel tasks in case of new pushes to the same branch. By default, Cirrus CI auto-cancels
all tasks for non default branch (for most repositories master branch) but this behavior can be changed by specifying
auto_cancellation field:
Stateful Tasks¶
It's possible to tell Cirrus CI that a certain task is stateful and Cirrus CI will use a slightly different scheduling algorithm to minimize chances of such tasks being interrupted. Stateful tasks are intended to use low CPU count. Scheduling times of such stateful tasks might be a bit longer then usual especially for tasks with high CPU requirements.
By default, Cirrus CI marks a task as stateful if its name contains one of the following terms: deploy, push, publish,
upload or release. Otherwise, you can explicitly mark a task as stateful via stateful field:
Failure Toleration¶
Sometimes tasks can play a role of sanity checks. For example, a task can check that your library is working with the latest nightly
version of some dependency package. It will be great to be notified about such failures but it's not necessary to fail the
whole build when a failure occurs. Cirrus CI has the allow_failures keyword which will make a task to not affect the overall status of a build.
Skipping Notifications
You can also skip posting red statuses to GitHub via skip_notifications field.
It can help to track potential issues overtime without distracting the main workflow.
Manual tasks¶
By default a Cirrus CI task is automatically triggered when all its dependency tasks
finished successfully. Sometimes though, it can be very handy to trigger some tasks manually, for example, perform a
deployment to staging for manual testing upon all automation checks have succeeded. In order change the default behavior
please use trigger_type field like this:
task:
name: "Staging Deploy"
trigger_type: manual
depends_on:
- Tests (Unit)
- Tests (Ingegration)
- Lint
You'll be able to manually trigger such paused tasks via Cirrus CI Web UI or directly from GitHub Checks page.
Task Execution Lock¶
Some CI tasks perform external operations which are required to be executed one at a time. For example, parallel deploys
to the same environment is usually a bad idea. In order to restrict parallel execution of a certain task within a repository,
you can use execution_lock to specify a task's lock key, a unique string that will be used to make sure that any tasks with the same execution_lock string
are executed one at a time. Here is an example of how to make sure deployments
on a specific branch can not run in parallel:
You'll be able to manually trigger such paused tasks via the Cirrus CI Web Dashboard or directly from the commit's checks page on GitHub.
Required PR Labels¶
Similar to manual tasks Cirrus CI can pause execution of tasks until a corresponding PR gets labeled.
This can be particular useful when you'd like to do an initial review before running all unit and integration
tests on every supported platform. Use the required_pr_labels field to specify
a list of labels a PR requires to have in order to trigger a task. Here is a simple example of .cirrus.yml config
that automatically runs a linting tool but requires initial-review label being presented in order to run tests:
Note: required_pr_labels has no effect on tasks created for non-PR builds.
You can also require multiple labels to continue executing the task for even more flexibility:
In the example above both initial-review and ready-for-staging labels should be presented on a PR in order to perform
a deployment via deploy task.
HTTP Cache¶
For the most cases regular caching mechanism where Cirrus CI caches a folder is more than enough. But modern build systems like Gradle, Bazel and Pants can take advantage of remote caching. Remote caching is when a build system uploads and downloads intermediate results of a build execution while the build itself is still executing.
Cirrus CI agent starts a local caching server and exposes it via CIRRUS_HTTP_CACHE_HOST environments variable. Caching server
supports GET, POST, HEAD and DELETE requests to upload, download, check presence and delete artifacts.
Info
If port 12321 is available CIRRUS_HTTP_CACHE_HOST will be equal to localhost:12321.
For example running the following command:
...has the same effect as the following caching instruction:
Info
To see how HTTP Cache can be used with Gradle's Build Cache please check this example.
Additional Containers¶
Sometimes one container is not enough to run a CI build. For example, your application might use a MySQL database as a storage. In this case you most likely want a MySQL instance running for your tests.
One option here is to pre-install MySQL and use a background_script to start it. This
approach has some inconveniences like the need to pre-install MySQL by building a custom Docker container.
For such use cases Cirrus CI allows to run additional containers in parallel with the main container that executes a task.
Each additional container is defined under additional_containers keyword in .cirrus.yml. Each additional container
should have a unique name and specify at least a container image.
Normally, you would also specify a port (or ports, if there are many) to instruct the Cirrus CI to configure the networking between the containers and wait for the ports to be available before running the task.
In the example below we use an official MySQL Docker image that exposes
the standard MySQL port (3306). Tests will be able to access MySQL instance via localhost:3306.
Additional container can be very handy in many scenarios. Please check Cirrus CI catalog of examples for more details.
Default Resources
By default, each additional container will get 0.5 CPU and 512Mi of memory. These values can be configured as usual
via cpu and memory fields.
Port Mapping
It's also possible to map ports of additional containers by using <HOST_PORT>:<CONTAINER_PORT> format for the port field.
For example, port: 80:8080 will map port 8080 of the container to be available on local port 80 within a task.
Note: don't use port mapping unless absolutely necessary. A perfect use case is when you have several additional containers which start the service on the same port and there's no easy way to change that. Port mapping limits the number of places the container can be scheduled and will affect how fast such tasks are scheduled.
To specify multiple mappings use the ports field, instead of the port:
Overriding Default Command
It's also possible to override the default CMD of an additional container via command field:
Warning
Note that additional_containers can be used only with Community Cluster
or Google's Kubernetes Engine.
Embedded Badges¶
Cirrus CI provides a way to embed a badge that can represent status of your builds into a ReadMe file or a website.
For example, this is a badge for cirruslabs/cirrus-ci-web repository that contains Cirrus CI's front end: 
In order to embed such a check into a "read-me" file or your website, just use a URL to a badge that looks like this:
If you want a badge for a particular branch, use the ?branch=<BRANCH NAME> query parameter (at the end of the URL) like this:
By default, Cirrus picks the latest build in a final state for the repository or a particular branch if branch parameter is specified. It's also possible to explicitly set a concrete build to use with ?buildId=<BUILD ID> query parameter.
If you want a badge for a particular task within the latest finished build, use the ?task=<TASK NAME> query parameter (at the end of the URL) like this:
You can even pick a specific script instruction within the task with an additional script=<SCRIPT NAME> parameter:
Badges in Markdown¶
Here is how Cirrus CI's badge can be embeded in a Markdown file:
[](https://cirrus-ci.com/github/<USER OR ORGANIZATION>/<REPOSITORY>)
CCTray XML¶
Cirrus CI supports exporting information about the latest repository builds via the CCTray XML format, using the following URL format:
Some tools with support of CCtray are:
- CCMenu (macOS Native build status monitor).
- Barklarm (Open Source multiplatform alarm and build status monitor).
- Nevergreen (Build radiation service).
Note: for private repositories you'll need to configure access token.