# GitLab CI/CD Variables When receiving a job from GitLab CI, the [Runner] prepares the build environment. It starts by setting a list of **predefined variables** (environment variables) and a list of **user-defined variables**. ## Priority of variables The variables can be overwritten and they take precedence over each other in this order: 1. [Trigger variables][triggers] or [scheduled pipeline variables](../../user/project/pipelines/schedules.md#making-use-of-scheduled-pipeline-variables) (take precedence over all) 1. Project-level [variables](#variables) or [protected variables](#protected-variables) 1. Group-level [variables](#variables) or [protected variables](#protected-variables) 1. YAML-defined [job-level variables](../yaml/README.md#variables) 1. YAML-defined [global variables](../yaml/README.md#variables) 1. [Deployment variables](#deployment-variables) 1. [Predefined variables](#predefined-variables-environment-variables) (are the lowest in the chain) For example, if you define `API_TOKEN=secure` as a project variable and `API_TOKEN=yaml` in your `.gitlab-ci.yml`, the `API_TOKEN` will take the value `secure` as the project variables are higher in the chain. ## Unsupported variables There are cases where some variables cannot be used in the context of a `.gitlab-ci.yml` definition (for example under `script`). Read more about which variables are [not supported](where_variables_can_be_used.md). ## Predefined variables (Environment variables) Some of the predefined environment variables are available only if a minimum version of [GitLab Runner][runner] is used. Consult the table below to find the version of Runner required. >**Note:** Starting with GitLab 9.0, we have deprecated some variables. Read the [9.0 Renaming](#9-0-renaming) section to find out their replacements. **You are strongly advised to use the new variables as we will remove the old ones in future GitLab releases.** | Variable | GitLab | Runner | Description | |-------------------------------- |--------|--------|-------------| | **ARTIFACT_DOWNLOAD_ATTEMPTS** | 8.15 | 1.9 | Number of attempts to download artifacts running a job | | **CI** | all | 0.4 | Mark that job is executed in CI environment | | **CI_COMMIT_REF_NAME** | 9.0 | all | The branch or tag name for which project is built | | **CI_COMMIT_REF_SLUG** | 9.0 | all | `$CI_COMMIT_REF_NAME` lowercased, shortened to 63 bytes, and with everything except `0-9` and `a-z` replaced with `-`. No leading / trailing `-`. Use in URLs, host names and domain names. | | **CI_COMMIT_SHA** | 9.0 | all | The commit revision for which project is built | | **CI_COMMIT_TAG** | 9.0 | 0.5 | The commit tag name. Present only when building tags. | | **CI_COMMIT_MESSAGE** | 10.8 | all | The full commit message. | | **CI_COMMIT_TITLE** | 10.8 | all | The title of the commit - the full first line of the message | | **CI_COMMIT_DESCRIPTION** | 10.8 | all | The description of the commit: the message without first line, if the title is shorter than 100 characters; full message in other case. | | **CI_CONFIG_PATH** | 9.4 | 0.5 | The path to CI config file. Defaults to `.gitlab-ci.yml` | | **CI_DEBUG_TRACE** | all | 1.7 | Whether [debug tracing](#debug-tracing) is enabled | | **CI_DEPLOY_USER** | 10.8 | all | Authentication username of the [GitLab Deploy Token][gitlab-deploy-token], only present if the Project has one related.| | **CI_DEPLOY_PASSWORD** | 10.8 | all | Authentication password of the [GitLab Deploy Token][gitlab-deploy-token], only present if the Project has one related.| | **CI_DISPOSABLE_ENVIRONMENT** | all | 10.1 | Marks that the job is executed in a disposable environment (something that is created only for this job and disposed of/destroyed after the execution - all executors except `shell` and `ssh`). If the environment is disposable, it is set to true, otherwise it is not defined at all. | | **CI_ENVIRONMENT_NAME** | 8.15 | all | The name of the environment for this job | | **CI_ENVIRONMENT_SLUG** | 8.15 | all | A simplified version of the environment name, suitable for inclusion in DNS, URLs, Kubernetes labels, etc. | | **CI_ENVIRONMENT_URL** | 9.3 | all | The URL of the environment for this job | | **CI_JOB_ID** | 9.0 | all | The unique id of the current job that GitLab CI uses internally | | **CI_JOB_MANUAL** | 8.12 | all | The flag to indicate that job was manually started | | **CI_JOB_NAME** | 9.0 | 0.5 | The name of the job as defined in `.gitlab-ci.yml` | | **CI_JOB_STAGE** | 9.0 | 0.5 | The name of the stage as defined in `.gitlab-ci.yml` | | **CI_JOB_TOKEN** | 9.0 | 1.2 | Token used for authenticating with the GitLab Container Registry | | **CI_JOB_URL** | 11.1 | 0.5 | Job details URL | | **CI_REPOSITORY_URL** | 9.0 | all | The URL to clone the Git repository | | **CI_RUNNER_DESCRIPTION** | 8.10 | 0.5 | The description of the runner as saved in GitLab | | **CI_RUNNER_ID** | 8.10 | 0.5 | The unique id of runner being used | | **CI_RUNNER_TAGS** | 8.10 | 0.5 | The defined runner tags | | **CI_RUNNER_VERSION** | all | 10.6 | GitLab Runner version that is executing the current job | | **CI_RUNNER_REVISION** | all | 10.6 | GitLab Runner revision that is executing the current job | | **CI_RUNNER_EXECUTABLE_ARCH** | all | 10.6 | The OS/architecture of the GitLab Runner executable (note that this is not necessarily the same as the environment of the executor) | | **CI_PIPELINE_ID** | 8.10 | 0.5 | The unique id of the current pipeline that GitLab CI uses internally | | **CI_PIPELINE_IID** | 11.0 | all | The unique id of the current pipeline scoped to project | | **CI_PIPELINE_TRIGGERED** | all | all | The flag to indicate that job was [triggered] | | **CI_PIPELINE_SOURCE** | 10.0 | all | Indicates how the pipeline was triggered. Possible options are: `push`, `web`, `trigger`, `schedule`, `api`, and `pipeline`. For pipelines created before GitLab 9.5, this will show as `unknown` | | **CI_PROJECT_DIR** | all | all | The full path where the repository is cloned and where the job is run | | **CI_PROJECT_ID** | all | all | The unique id of the current project that GitLab CI uses internally | | **CI_PROJECT_NAME** | 8.10 | 0.5 | The project name that is currently being built (actually it is project folder name) | | **CI_PROJECT_NAMESPACE** | 8.10 | 0.5 | The project namespace (username or groupname) that is currently being built | | **CI_PROJECT_PATH** | 8.10 | 0.5 | The namespace with project name | | **CI_PROJECT_PATH_SLUG** | 9.3 | all | `$CI_PROJECT_PATH` lowercased and with everything except `0-9` and `a-z` replaced with `-`. Use in URLs and domain names. | | **CI_PIPELINE_URL** | 11.1 | 0.5 | Pipeline details URL | | **CI_PROJECT_URL** | 8.10 | 0.5 | The HTTP address to access project | | **CI_PROJECT_VISIBILITY** | 10.3 | all | The project visibility (internal, private, public) | | **CI_REGISTRY** | 8.10 | 0.5 | If the Container Registry is enabled it returns the address of GitLab's Container Registry | | **CI_REGISTRY_IMAGE** | 8.10 | 0.5 | If the Container Registry is enabled for the project it returns the address of the registry tied to the specific project | | **CI_REGISTRY_PASSWORD** | 9.0 | all | The password to use to push containers to the GitLab Container Registry | | **CI_REGISTRY_USER** | 9.0 | all | The username to use to push containers to the GitLab Container Registry | | **CI_SERVER** | all | all | Mark that job is executed in CI environment | | **CI_SERVER_NAME** | all | all | The name of CI server that is used to coordinate jobs | | **CI_SERVER_REVISION** | all | all | GitLab revision that is used to schedule jobs | | **CI_SERVER_VERSION** | all | all | GitLab version that is used to schedule jobs | | **CI_SHARED_ENVIRONMENT** | all | 10.1 | Marks that the job is executed in a shared environment (something that is persisted across CI invocations like `shell` or `ssh` executor). If the environment is shared, it is set to true, otherwise it is not defined at all. | | **GET_SOURCES_ATTEMPTS** | 8.15 | 1.9 | Number of attempts to fetch sources running a job | | **GITLAB_CI** | all | all | Mark that job is executed in GitLab CI environment | | **GITLAB_USER_EMAIL** | 8.12 | all | The email of the user who started the job | | **GITLAB_USER_ID** | 8.12 | all | The id of the user who started the job | | **GITLAB_USER_LOGIN** | 10.0 | all | The login username of the user who started the job | | **GITLAB_USER_NAME** | 10.0 | all | The real name of the user who started the job | | **RESTORE_CACHE_ATTEMPTS** | 8.15 | 1.9 | Number of attempts to restore the cache running a job | ## 9.0 Renaming To follow conventions of naming across GitLab, and to further move away from the `build` term and toward `job` CI variables have been renamed for the 9.0 release. >**Note:** Starting with GitLab 9.0, we have deprecated the `$CI_BUILD_*` variables. **You are strongly advised to use the new variables as we will remove the old ones in future GitLab releases.** | 8.x name | 9.0+ name | | --------------------- |------------------------ | | `CI_BUILD_ID` | `CI_JOB_ID` | | `CI_BUILD_REF` | `CI_COMMIT_SHA` | | `CI_BUILD_TAG` | `CI_COMMIT_TAG` | | `CI_BUILD_REF_NAME` | `CI_COMMIT_REF_NAME` | | `CI_BUILD_REF_SLUG` | `CI_COMMIT_REF_SLUG` | | `CI_BUILD_NAME` | `CI_JOB_NAME` | | `CI_BUILD_STAGE` | `CI_JOB_STAGE` | | `CI_BUILD_REPO` | `CI_REPOSITORY_URL` | | `CI_BUILD_TRIGGERED` | `CI_PIPELINE_TRIGGERED` | | `CI_BUILD_MANUAL` | `CI_JOB_MANUAL` | | `CI_BUILD_TOKEN` | `CI_JOB_TOKEN` | ## `.gitlab-ci.yml` defined variables >**Note:** This feature requires GitLab Runner 0.5.0 or higher and GitLab CI 7.14 or higher. GitLab CI allows you to add to `.gitlab-ci.yml` variables that are set in the build environment. The variables are hence saved in the repository, and they are meant to store non-sensitive project configuration, e.g., `RAILS_ENV` or `DATABASE_URL`. For example, if you set the variable below globally (not inside a job), it will be used in all executed commands and scripts: ```yaml variables: DATABASE_URL: "postgres://postgres@postgres/my_database" ``` The YAML-defined variables are also set to all created [service containers](../docker/using_docker_images.md), thus allowing to fine tune them. Variables can be defined at a global level, but also at a job level. To turn off global defined variables in your job, define an empty hash: ```yaml job_name: variables: {} ``` You are able to use other variables inside your variable definition (or escape them with `$$`): ```yaml variables: LS_CMD: 'ls $FLAGS $$TMP_DIR' FLAGS: '-al' script: - 'eval $LS_CMD' # will execute 'ls -al $TMP_DIR' ``` ## Variables NOTE: **Note:** Group-level variables were added in GitLab 9.4. CAUTION: **Important:** Be aware that variables are not masked, and their values can be shown in the job logs if explicitly asked to do so. If your project is public or internal, you can set the pipelines private from your [project's Pipelines settings](../../user/project/pipelines/settings.md#visibility-of-pipelines). Follow the discussion in issue [#13784][ce-13784] for masking the variables. GitLab CI allows you to define per-project or per-group variables that are set in the pipeline environment. The variables are stored out of the repository (not in `.gitlab-ci.yml`) and are securely passed to GitLab Runner making them available during a pipeline run. It's the recommended method to use for storing things like passwords, SSH keys and credentials. Project-level variables can be added by going to your project's **Settings > CI/CD**, then finding the section called **Variables**. Likewise, group-level variables can be added by going to your group's **Settings > CI/CD**, then finding the section called **Variables**. Any variables of [subgroups] will be inherited recursively. ![Variables](img/secret_variables.png) Once you set them, they will be available for all subsequent pipelines. You can also [protect your variables](#protected-variables). ### Protected variables >**Notes:** This feature requires GitLab 9.3 or higher. Variables could be protected. Whenever a variable is protected, it would only be securely passed to pipelines running on the [protected branches] or [protected tags]. The other pipelines would not get any protected variables. Protected variables can be added by going to your project's **Settings > CI/CD**, then finding the section called **Variables**, and check "Protected". Once you set them, they will be available for all subsequent pipelines. ## Deployment variables >**Note:** This feature requires GitLab CI 8.15 or higher. [Project services](../../user/project/integrations/project_services.md) that are responsible for deployment configuration may define their own variables that are set in the build environment. These variables are only defined for [deployment jobs](../environments.md). Please consult the documentation of the project services that you are using to learn which variables they define. An example project service that defines deployment variables is the [Kubernetes integration](../../user/project/clusters/index.md#deployment-variables). ## Debug tracing > Introduced in GitLab Runner 1.7. CAUTION: **Warning:** Enabling debug tracing can have severe security implications. The output **will** contain the content of all your variables and any other secrets! The output **will** be uploaded to the GitLab server and made visible in job traces! By default, GitLab Runner hides most of the details of what it is doing when processing a job. This behavior keeps job traces short, and prevents secrets from being leaked into the trace unless your script writes them to the screen. If a job isn't working as expected, this can make the problem difficult to investigate; in these cases, you can enable debug tracing in `.gitlab-ci.yml`. Available on GitLab Runner v1.7+, this feature enables the shell's execution trace, resulting in a verbose job trace listing all commands that were run, variables that were set, etc. Before enabling this, you should ensure jobs are visible to [team members only](../../user/permissions.md#project-features). You should also [erase](../pipelines.md#seeing-build-status) all generated job traces before making them visible again. To enable debug traces, set the `CI_DEBUG_TRACE` variable to `true`: ```yaml job_name: variables: CI_DEBUG_TRACE: "true" ``` Example truncated output with debug trace set to true: ```bash ... export CI_SERVER_TLS_CA_FILE="/builds/gitlab-examples/ci-debug-trace.tmp/CI_SERVER_TLS_CA_FILE" if [[ -d "/builds/gitlab-examples/ci-debug-trace/.git" ]]; then echo $'\''\x1b[32;1mFetching changes...\x1b[0;m'\'' $'\''cd'\'' "/builds/gitlab-examples/ci-debug-trace" $'\''git'\'' "config" "fetch.recurseSubmodules" "false" $'\''rm'\'' "-f" ".git/index.lock" $'\''git'\'' "clean" "-ffdx" $'\''git'\'' "reset" "--hard" $'\''git'\'' "remote" "set-url" "origin" "https://gitlab-ci-token:xxxxxxxxxxxxxxxxxxxx@example.com/gitlab-examples/ci-debug-trace.git" $'\''git'\'' "fetch" "origin" "--prune" "+refs/heads/*:refs/remotes/origin/*" "+refs/tags/*:refs/tags/*" else $'\''mkdir'\'' "-p" "/builds/gitlab-examples/ci-debug-trace.tmp/git-template" $'\''rm'\'' "-r" "-f" "/builds/gitlab-examples/ci-debug-trace" $'\''git'\'' "config" "-f" "/builds/gitlab-examples/ci-debug-trace.tmp/git-template/config" "fetch.recurseSubmodules" "false" echo $'\''\x1b[32;1mCloning repository...\x1b[0;m'\'' $'\''git'\'' "clone" "--no-checkout" "https://gitlab-ci-token:xxxxxxxxxxxxxxxxxxxx@example.com/gitlab-examples/ci-debug-trace.git" "/builds/gitlab-examples/ci-debug-trace" "--template" "/builds/gitlab-examples/ci-debug-trace.tmp/git-template" $'\''cd'\'' "/builds/gitlab-examples/ci-debug-trace" fi echo $'\''\x1b[32;1mChecking out dd648b2e as master...\x1b[0;m'\'' $'\''git'\'' "checkout" "-f" "-q" "dd648b2e48ce6518303b0bb580b2ee32fadaf045" ' +++ hostname ++ echo 'Running on runner-8a2f473d-project-1796893-concurrent-0 via runner-8a2f473d-machine-1480971377-317a7d0f-digital-ocean-4gb...' Running on runner-8a2f473d-project-1796893-concurrent-0 via runner-8a2f473d-machine-1480971377-317a7d0f-digital-ocean-4gb... ++ export CI=true ++ CI=true ++ export CI_DEBUG_TRACE=false ++ CI_DEBUG_TRACE=false ++ export CI_COMMIT_SHA=dd648b2e48ce6518303b0bb580b2ee32fadaf045 ++ CI_COMMIT_SHA=dd648b2e48ce6518303b0bb580b2ee32fadaf045 ++ export CI_COMMIT_BEFORE_SHA=dd648b2e48ce6518303b0bb580b2ee32fadaf045 ++ CI_COMMIT_BEFORE_SHA=dd648b2e48ce6518303b0bb580b2ee32fadaf045 ++ export CI_COMMIT_REF_NAME=master ++ CI_COMMIT_REF_NAME=master ++ export CI_JOB_ID=7046507 ++ CI_JOB_ID=7046507 ++ export CI_REPOSITORY_URL=https://gitlab-ci-token:xxxxxxxxxxxxxxxxxxxx@example.com/gitlab-examples/ci-debug-trace.git ++ CI_REPOSITORY_URL=https://gitlab-ci-token:xxxxxxxxxxxxxxxxxxxx@example.com/gitlab-examples/ci-debug-trace.git ++ export CI_JOB_TOKEN=xxxxxxxxxxxxxxxxxxxx ++ CI_JOB_TOKEN=xxxxxxxxxxxxxxxxxxxx ++ export CI_PROJECT_ID=1796893 ++ CI_PROJECT_ID=1796893 ++ export CI_PROJECT_DIR=/builds/gitlab-examples/ci-debug-trace ++ CI_PROJECT_DIR=/builds/gitlab-examples/ci-debug-trace ++ export CI_SERVER=yes ++ CI_SERVER=yes ++ export 'CI_SERVER_NAME=GitLab CI' ++ CI_SERVER_NAME='GitLab CI' ++ export CI_SERVER_VERSION= ++ CI_SERVER_VERSION= ++ export CI_SERVER_REVISION= ++ CI_SERVER_REVISION= ++ export GITLAB_CI=true ++ GITLAB_CI=true ++ export CI=true ++ CI=true ++ export GITLAB_CI=true ++ GITLAB_CI=true ++ export CI_JOB_ID=7046507 ++ CI_JOB_ID=7046507 ++ export CI_JOB_TOKEN=xxxxxxxxxxxxxxxxxxxx ++ CI_JOB_TOKEN=xxxxxxxxxxxxxxxxxxxx ++ export CI_COMMIT_REF=dd648b2e48ce6518303b0bb580b2ee32fadaf045 ++ CI_COMMIT_REF=dd648b2e48ce6518303b0bb580b2ee32fadaf045 ++ export CI_COMMIT_BEFORE_SHA=dd648b2e48ce6518303b0bb580b2ee32fadaf045 ++ CI_COMMIT_BEFORE_SHA=dd648b2e48ce6518303b0bb580b2ee32fadaf045 ++ export CI_COMMIT_REF_NAME=master ++ CI_COMMIT_REF_NAME=master ++ export CI_COMMIT_NAME=debug_trace ++ CI_JOB_NAME=debug_trace ++ export CI_JOB_STAGE=test ++ CI_JOB_STAGE=test ++ export CI_SERVER_NAME=GitLab ++ CI_SERVER_NAME=GitLab ++ export CI_SERVER_VERSION=8.14.3-ee ++ CI_SERVER_VERSION=8.14.3-ee ++ export CI_SERVER_REVISION=82823 ++ CI_SERVER_REVISION=82823 ++ export CI_PROJECT_ID=17893 ++ CI_PROJECT_ID=17893 ++ export CI_PROJECT_NAME=ci-debug-trace ++ CI_PROJECT_NAME=ci-debug-trace ++ export CI_PROJECT_PATH=gitlab-examples/ci-debug-trace ++ CI_PROJECT_PATH=gitlab-examples/ci-debug-trace ++ export CI_PROJECT_NAMESPACE=gitlab-examples ++ CI_PROJECT_NAMESPACE=gitlab-examples ++ export CI_PROJECT_URL=https://example.com/gitlab-examples/ci-debug-trace ++ CI_PROJECT_URL=https://example.com/gitlab-examples/ci-debug-trace ++ export CI_PIPELINE_ID=52666 ++ CI_PIPELINE_ID=52666 ++ export CI_PIPELINE_IID=123 ++ CI_PIPELINE_IID=123 ++ export CI_RUNNER_ID=1337 ++ CI_RUNNER_ID=1337 ++ export CI_RUNNER_DESCRIPTION=shared-runners-manager-1.example.com ++ CI_RUNNER_DESCRIPTION=shared-runners-manager-1.example.com ++ export 'CI_RUNNER_TAGS=shared, docker, linux, ruby, mysql, postgres, mongo' ++ CI_RUNNER_TAGS='shared, docker, linux, ruby, mysql, postgres, mongo' ++ export CI_REGISTRY=registry.example.com ++ CI_REGISTRY=registry.example.com ++ export CI_DEBUG_TRACE=true ++ CI_DEBUG_TRACE=true ++ export GITLAB_USER_ID=42 ++ GITLAB_USER_ID=42 ++ export GITLAB_USER_EMAIL=user@example.com ++ GITLAB_USER_EMAIL=user@example.com ++ export VERY_SECURE_VARIABLE=imaverysecurevariable ++ VERY_SECURE_VARIABLE=imaverysecurevariable ++ mkdir -p /builds/gitlab-examples/ci-debug-trace.tmp ++ echo -n '-----BEGIN CERTIFICATE----- MIIFQzCCBCugAwIBAgIRAL/ElDjuf15xwja1ZnCocWAwDQYJKoZIhvcNAQELBQAw' ... ``` ## Using the CI variables in your job scripts All variables are set as environment variables in the build environment, and they are accessible with normal methods that are used to access such variables. In most cases `bash` or `sh` is used to execute the job script. To access environment variables, use the syntax for your Runner's [shell][shellexecutors]. | Shell | Usage | |----------------------|-----------------| | bash/sh | `$variable` | | windows batch | `%variable%` | | PowerShell | `$env:variable` | To access environment variables in bash, prefix the variable name with (`$`): ```yaml job_name: script: - echo $CI_JOB_ID ``` To access environment variables in **Windows Batch**, surround the variable with (`%`): ```yaml job_name: script: - echo %CI_JOB_ID% ``` To access environment variables in a **Windows PowerShell** environment, prefix the variable name with (`$env:`): ```yaml job_name: script: - echo $env:CI_JOB_ID ``` You can also list all environment variables with the `export` command, but be aware that this will also expose the values of all the variables you set, in the job log: ```yaml job_name: script: - export ``` Example values: ```bash export CI_JOB_ID="50" export CI_COMMIT_SHA="1ecfd275763eff1d6b4844ea3168962458c9f27a" export CI_COMMIT_REF_NAME="master" export CI_REPOSITORY_URL="https://gitlab-ci-token:abcde-1234ABCD5678ef@example.com/gitlab-org/gitlab-ce.git" export CI_COMMIT_TAG="1.0.0" export CI_JOB_NAME="spec:other" export CI_JOB_STAGE="test" export CI_JOB_MANUAL="true" export CI_JOB_TRIGGERED="true" export CI_JOB_TOKEN="abcde-1234ABCD5678ef" export CI_PIPELINE_ID="1000" export CI_PIPELINE_IID="10" export CI_PROJECT_ID="34" export CI_PROJECT_DIR="/builds/gitlab-org/gitlab-ce" export CI_PROJECT_NAME="gitlab-ce" export CI_PROJECT_NAMESPACE="gitlab-org" export CI_PROJECT_PATH="gitlab-org/gitlab-ce" export CI_PROJECT_URL="https://example.com/gitlab-org/gitlab-ce" export CI_REGISTRY="registry.example.com" export CI_REGISTRY_IMAGE="registry.example.com/gitlab-org/gitlab-ce" export CI_RUNNER_ID="10" export CI_RUNNER_DESCRIPTION="my runner" export CI_RUNNER_TAGS="docker, linux" export CI_SERVER="yes" export CI_SERVER_NAME="GitLab" export CI_SERVER_REVISION="70606bf" export CI_SERVER_VERSION="8.9.0" export GITLAB_USER_ID="42" export GITLAB_USER_EMAIL="user@example.com" export CI_REGISTRY_USER="gitlab-ci-token" export CI_REGISTRY_PASSWORD="longalfanumstring" ``` ## Variables expressions > Variables expressions were added in GitLab 10.7. It is possible to use variables expressions with only / except policies in `.gitlab-ci.yml`. By using this approach you can limit what jobs are going to be created within a pipeline after pushing a code to GitLab. This is particularly useful in combination with variables and triggered pipeline variables. ```yaml deploy: script: cap staging deploy environment: staging only: variables: - $RELEASE == "staging" - $STAGING ``` Each expression provided is going to be evaluated before creating a pipeline. If any of the conditions in `variables` evaluates to truth when using `only`, a new job is going to be created. If any of the expressions evaluates to truth when `except` is being used, a job is not going to be created. This follows usual rules for [`only` / `except` policies][builds-policies]. ### Supported syntax Below you can find supported syntax reference: 1. Equality matching using a string > Example: `$VARIABLE == "some value"` You can use equality operator `==` to compare a variable content to a string. We support both, double quotes and single quotes to define a string value, so both `$VARIABLE == "some value"` and `$VARIABLE == 'some value'` are supported. `"some value" == $VARIABLE` is correct too. 1. Checking for an undefined value > Example: `$VARIABLE == null` It sometimes happens that you want to check whether a variable is defined or not. To do that, you can compare a variable to `null` keyword, like `$VARIABLE == null`. This expression is going to evaluate to truth if variable is not defined. 1. Checking for an empty variable > Example: `$VARIABLE == ""` If you want to check whether a variable is defined, but is empty, you can simply compare it against an empty string, like `$VAR == ''`. 1. Comparing two variables > Example: `$VARIABLE_1 == $VARIABLE_2` It is possible to compare two variables. This is going to compare values of these variables. 1. Variable presence check > Example: `$STAGING` If you only want to create a job when there is some variable present, which means that it is defined and non-empty, you can simply use variable name as an expression, like `$STAGING`. If `$STAGING` variable is defined, and is non empty, expression will evaluate to truth. `$STAGING` value needs to a string, with length higher than zero. Variable that contains only whitespace characters is not an empty variable. 1. Pattern matching _(added in 11.0)_ > Example: `$VARIABLE =~ /^content.*/` It is possible perform pattern matching against a variable and regular expression. Expression like this evaluates to truth if matches are found. Pattern matching is case-sensitive by default. Use `i` flag modifier, like `/pattern/i` to make a pattern case-insensitive. [ce-13784]: https://gitlab.com/gitlab-org/gitlab-ce/issues/13784 "Simple protection of CI variables" [eep]: https://about.gitlab.com/pricing/ "Available only in GitLab Premium" [envs]: ../environments.md [protected branches]: ../../user/project/protected_branches.md [protected tags]: ../../user/project/protected_tags.md [runner]: https://docs.gitlab.com/runner/ [shellexecutors]: https://docs.gitlab.com/runner/executors/ [triggered]: ../triggers/README.md [triggers]: ../triggers/README.md#pass-job-variables-to-a-trigger [subgroups]: ../../user/group/subgroups/index.md [builds-policies]: ../yaml/README.md#only-and-except-complex [gitlab-deploy-token]: ../../user/project/deploy_tokens/index.md#gitlab-deploy-token