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stage | group | info | type |
---|---|---|---|
Verify | Pipeline Authoring | To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/product/ux/technical-writing/#assignments | reference |
Where variables can be used (FREE)
As it's described in the CI/CD variables documentation, you can define many different variables. Some of them can be used for all GitLab CI/CD features, but some of them are more or less limited.
This document describes where and how the different types of variables can be used.
Variables usage
There are two places defined variables can be used. On the:
- GitLab side, in the
.gitlab-ci.yml
file. - The GitLab Runner side, in
config.toml
.
.gitlab-ci.yml
file
Definition | Can be expanded? | Expansion place | Description |
---|---|---|---|
after_script |
yes | Script execution shell | The variable expansion is made by the execution shell environment. |
artifacts:name |
yes | Runner | The variable expansion is made by GitLab Runner's shell environment. |
before_script |
yes | Script execution shell | The variable expansion is made by the execution shell environment |
cache:key |
yes | Runner | The variable expansion is made by GitLab Runner's internal variable expansion mechanism. |
environment:name |
yes | GitLab | Similar to environment:url , but the variables expansion doesn't support the following:- CI_ENVIRONMENT_* variables.- Persisted variables. |
environment:url |
yes | GitLab | The variable expansion is made by the internal variable expansion mechanism in GitLab. Supported are all variables defined for a job (project/group variables, variables from .gitlab-ci.yml , variables from triggers, variables from pipeline schedules).Not supported are variables defined in the GitLab Runner config.toml and variables created in the job's script . |
environment:auto_stop_in |
yes | GitLab | The variable expansion is made by the internal variable expansion mechanism in GitLab. The value of the variable being substituted should be a period of time in a human readable natural language form. See possible inputs for more information. |
except:variables |
no | Not applicable | The variable must be in the form of $variable . Not supported are the following:- CI_ENVIRONMENT_* variables, except CI_ENVIRONMENT_NAME which is supported.- Persisted variables. |
image |
yes | Runner | The variable expansion is made by GitLab Runner's internal variable expansion mechanism. |
include |
yes | GitLab | The variable expansion is made by the internal variable expansion mechanism in GitLab. See Use variables with include for more information on supported variables. |
only:variables |
no | Not applicable | The variable must be in the form of $variable . Not supported are the following:- CI_ENVIRONMENT_* variables, except CI_ENVIRONMENT_NAME which is supported.- Persisted variables. |
resource_group |
yes | GitLab | Similar to environment:url , but the variables expansion doesn't support the following:- CI_ENVIRONMENT_URL - Persisted variables. |
rules:exists |
yes | GitLab | The variable expansion is made by the internal variable expansion mechanism in GitLab. |
rules:if |
no | Not applicable | The variable must be in the form of $variable . Not supported are the following:- CI_ENVIRONMENT_* variables, except CI_ENVIRONMENT_NAME which is supported.- Persisted variables. |
script |
yes | Script execution shell | The variable expansion is made by the execution shell environment. |
services:name |
yes | Runner | The variable expansion is made by GitLab Runner's internal variable expansion mechanism. |
services |
yes | Runner | The variable expansion is made by GitLab Runner's internal variable expansion mechanism. |
tags |
yes | GitLab | The variable expansion is made by the internal variable expansion mechanism in GitLab. Introduced in GitLab 14.1. |
trigger and trigger:project |
yes | GitLab | The variable expansion is made by the internal variable expansion mechanism in GitLab. Variable expansion for trigger:project introduced in GitLab 15.3. |
variables |
yes | GitLab/Runner | The variable expansion is first made by the internal variable expansion mechanism in GitLab, and then any unrecognized or unavailable variables are expanded by GitLab Runner's internal variable expansion mechanism. |
workflow:name |
yes | GitLab | The variable expansion is made by the internal variable expansion mechanism in GitLab. Supported are all variables available in workflow :- Project/Group variables. - Global variables and workflow:rules:variables (when matching the rule).- Variables inherited from parent pipelines. - Variables from triggers. - Variables from pipeline schedules. Not supported are variables defined in the GitLab Runner config.toml , variables defined in jobs, or Persisted variables. |
config.toml
file
Definition | Can be expanded? | Description |
---|---|---|
runners.environment |
yes | The variable expansion is made by GitLab Runner's internal variable expansion mechanism |
runners.kubernetes.pod_labels |
yes | The Variable expansion is made by GitLab Runner's internal variable expansion mechanism |
runners.kubernetes.pod_annotations |
yes | The Variable expansion is made by GitLab Runner's internal variable expansion mechanism |
You can read more about config.toml
in the GitLab Runner docs.
Expansion mechanisms
There are three expansion mechanisms:
- GitLab
- GitLab Runner
- Execution shell environment
GitLab internal variable expansion mechanism
The expanded part needs to be in a form of $variable
, or ${variable}
or %variable%
.
Each form is handled in the same way, no matter which OS/shell handles the job,
because the expansion is done in GitLab before any runner gets the job.
Nested variable expansion
- Introduced in GitLab 13.10. Deployed behind the
variable_inside_variable
feature flag, disabled by default. - Enabled on GitLab.com in GitLab 14.3.
- Enabled on self-managed in GitLab 14.4.
- Feature flag
variable_inside_variable
removed in GitLab 14.5.
GitLab expands job variable values recursively before sending them to the runner. For example, in the following scenario:
- BUILD_ROOT_DIR: '${CI_BUILDS_DIR}'
- OUT_PATH: '${BUILD_ROOT_DIR}/out'
- PACKAGE_PATH: '${OUT_PATH}/pkg'
The runner receives a valid, fully-formed path. For example, if ${CI_BUILDS_DIR}
is /output
, then PACKAGE_PATH
would be /output/out/pkg
.
References to unavailable variables are left intact. In this case, the runner
attempts to expand the variable value at runtime.
For example, a variable like CI_BUILDS_DIR
is known by the runner only at runtime.
GitLab Runner internal variable expansion mechanism
- Supported: project/group variables,
.gitlab-ci.yml
variables,config.toml
variables, and variables from triggers, pipeline schedules, and manual pipelines. - Not supported: variables defined inside of scripts (for example,
export MY_VARIABLE="test"
).
The runner uses Go's os.Expand()
method for variable expansion. It means that it handles
only variables defined as $variable
and ${variable}
. What's also important, is that
the expansion is done only once, so nested variables may or may not work, depending on the
ordering of variables definitions, and whether nested variable expansion
is enabled in GitLab.
Execution shell environment
This is an expansion phase that takes place during the script
execution.
Its behavior depends on the shell used (bash
, sh
, cmd
, PowerShell). For example, if the job's
script
contains a line echo $MY_VARIABLE-${MY_VARIABLE_2}
, it should be properly handled
by bash/sh (leaving empty strings or some values depending whether the variables were
defined or not), but don't work with Windows' cmd
or PowerShell, since these shells
use a different variables syntax.
Supported:
- The
script
may use all available variables that are default for the shell (for example,$PATH
which should be present in all bash/sh shells) and all variables defined by GitLab CI/CD (project/group variables,.gitlab-ci.yml
variables,config.toml
variables, and variables from triggers and pipeline schedules). - The
script
may also use all variables defined in the lines before. So, for example, if you define a variableexport MY_VARIABLE="test"
:- In
before_script
, it works in the subsequent lines ofbefore_script
and all lines of the relatedscript
. - In
script
, it works in the subsequent lines ofscript
. - In
after_script
, it works in subsequent lines ofafter_script
.
- In
In the case of after_script
scripts, they can:
- Only use variables defined before the script within the same
after_script
section. - Not use variables defined in
before_script
andscript
.
These restrictions exist because after_script
scripts are executed in a
separated shell context.
Persisted variables
Some predefined variables are called "persisted".
Pipeline-level persisted variables:
CI_PIPELINE_ID
CI_PIPELINE_URL
Job-level persisted variables:
CI_JOB_ID
CI_JOB_URL
CI_JOB_TOKEN
CI_JOB_STARTED_AT
CI_REGISTRY_USER
CI_REGISTRY_PASSWORD
CI_REPOSITORY_URL
CI_DEPLOY_USER
CI_DEPLOY_PASSWORD
Persisted variables are:
- Supported for definitions where the "Expansion place" is:
- Runner.
- Script execution shell.
- Not supported:
- For definitions where the "Expansion place" is GitLab.
- In the
only
,except
, andrules
variables expressions.
Pipeline trigger jobs cannot use job-level persisted variables, but can use pipeline-level persisted variables.
Some of the persisted variables contain tokens and cannot be used by some definitions due to security reasons.
Variables with an environment scope
Variables defined with an environment scope are supported. Given that
there is a variable $STAGING_SECRET
defined in a scope of
review/staging/*
, the following job that is using dynamic environments
is created, based on the matching variable expression:
my-job:
stage: staging
environment:
name: review/$CI_JOB_STAGE/deploy
script:
- 'deploy staging'
rules:
- if: $STAGING_SECRET == 'something'