About workflow commands
Actions can communicate with the runner machine to set environment variables, output values used by other actions, add debug messages to the output logs, and other tasks.
Most workflow commands use the echo
command in a specific format, while others are invoked by writing to a file. For more information, see "Environment files".
echo "::workflow-command parameter1={data},parameter2={data}::{command value}"
Note: Workflow command and parameter names are not case-sensitive.
Warning: If you are using Command Prompt, omit double quote characters ("
) when using workflow commands.
Using workflow commands to access toolkit functions
The actions/toolkit includes a number of functions that can be executed as workflow commands. Use the ::
syntax to run the workflow commands within your YAML file; these commands are then sent to the runner over stdout
. For example, instead of using code to set an output, as below:
core.setOutput('SELECTED_COLOR', 'green');
You can use the set-output
command in your workflow to set the same value:
- name: Set selected color
run: echo '::set-output name=SELECTED_COLOR::green'
id: random-color-generator
- name: Get color
run: echo "The selected color is ${{ steps.random-color-generator.outputs.SELECTED_COLOR }}"
The following table shows which toolkit functions are available within a workflow:
Toolkit function | Equivalent workflow command |
---|---|
core.addPath | Accessible using environment file GITHUB_PATH |
core.debug | debug |
core.error | error |
core.endGroup | endgroup |
core.exportVariable | Accessible using environment file GITHUB_ENV |
core.getInput | Accessible using environment variable INPUT_{NAME} |
core.getState | Accessible using environment variable STATE_{NAME} |
core.isDebug | Accessible using environment variable RUNNER_DEBUG |
core.saveState | save-state |
core.setFailed | Used as a shortcut for ::error and exit 1 |
core.setOutput | set-output |
core.setSecret | add-mask |
core.startGroup | group |
core.warning | warning file |
Setting an output parameter
::set-output name={name}::{value}
Sets an action's output parameter.
Optionally, you can also declare output parameters in an action's metadata file. For more information, see "Metadata syntax for GitHub Actions."
Example
echo "::set-output name=action_fruit::strawberry"
Setting a debug message
::debug::{message}
Prints a debug message to the log. You must create a secret named ACTIONS_STEP_DEBUG
with the value true
to see the debug messages set by this command in the log. For more information, see "Enabling debug logging."
Example
echo "::debug::Set the Octocat variable"
Setting a warning message
::warning file={name},line={line},col={col}::{message}
Creates a warning message and prints the message to the log. You can optionally provide a filename (file
), line number (line
), and column (col
) number where the warning occurred.
Example
echo "::warning file=app.js,line=1,col=5::Missing semicolon"
Setting an error message
::error file={name},line={line},col={col}::{message}
Creates an error message and prints the message to the log. You can optionally provide a filename (file
), line number (line
), and column (col
) number where the error occurred.
Example
echo "::error file=app.js,line=10,col=15::Something went wrong"
Grouping log lines
::group::{title}
::endgroup::
Creates an expandable group in the log. To create a group, use the group
command and specify a title
. Anything you print to the log between the group
and endgroup
commands is nested inside an expandable entry in the log.
Example
echo "::group::My title"
echo "Inside group"
echo "::endgroup::"
Masking a value in log
::add-mask::{value}
Masking a value prevents a string or variable from being printed in the log. Each masked word separated by whitespace is replaced with the *
character. You can use an environment variable or string for the mask's value
.
Example masking a string
When you print "Mona The Octocat"
in the log, you'll see "***"
.
echo "::add-mask::Mona The Octocat"
Example masking an environment variable
When you print the variable MY_NAME
or the value "Mona The Octocat"
in the log, you'll see "***"
instead of "Mona The Octocat"
.
MY_NAME="Mona The Octocat"
echo "::add-mask::$MY_NAME"
Stopping and starting workflow commands
::stop-commands::{endtoken}
Stops processing any workflow commands. This special command allows you to log anything without accidentally running a workflow command. For example, you could stop logging to output an entire script that has comments.
Example stopping workflow commands
echo "::stop-commands::pause-logging"
To start workflow commands, pass the token that you used to stop workflow commands.
::{endtoken}::
Example starting workflow commands
echo "::pause-logging::"
Sending values to the pre and post actions
You can use the save-state
command to create environment variables for sharing with your workflow's pre:
or post:
actions. For example, you can create a file with the pre:
action, pass the file location to the main:
action, and then use the post:
action to delete the file. Alternatively, you could create a file with the main:
action, pass the file location to the post:
action, and also use the post:
action to delete the file.
If you have multiple pre:
or post:
actions, you can only access the saved value in the action where save-state
was used. For more information on the post:
action, see "Metadata syntax for GitHub Actions."
The save-state
command can only be run within an action, and is not available to YAML files. The saved value is stored as an environment value with the STATE_
prefix.
This example uses JavaScript to run the save-state
command. The resulting environment variable is named STATE_processID
with the value of 12345
:
console.log('::save-state name=processID::12345')
The STATE_processID
variable is then exclusively available to the cleanup script running under the main
action. This example runs in main
and uses JavaScript to display the value assigned to the STATE_processID
environment variable:
console.log("The running PID from the main action is: " + process.env.STATE_processID);
Environment Files
During the execution of a workflow, the runner generates temporary files that can be used to perform certain actions. The path to these files are exposed via environment variables. You will need to use UTF-8 encoding when writing to these files to ensure proper processing of the commands. Multiple commands can be written to the same file, separated by newlines.
Warning: Powershell does not use UTF-8 by default. Make sure you write files using the correct encoding. For example, you need to set UTF-8 encoding when you set the path:
steps:
- run: echo "mypath" | Out-File -FilePath $env:GITHUB_PATH -Encoding utf8 -Append
Setting an environment variable
echo "{name}={value}" >> $GITHUB_ENV
Creates or updates an environment variable for any actions running next in a job. The action that creates or updates the environment variable does not have access to the new value, but all subsequent actions in a job will have access. Environment variables are case-sensitive and you can include punctuation.
Example
steps:
- name: Set the value
id: step_one
run: |
echo "action_state=yellow" >> $GITHUB_ENV
- name: Use the value
id: step_two
run: |
echo "${{ env.action_state }}" # This will output 'yellow'
Multiline strings
For multiline strings, you may use a delimiter with the following syntax.
{name}<<{delimiter}
{value}
{delimiter}
Example
In this example, we use EOF
as a delimiter and set the JSON_RESPONSE
environment variable to the value of the curl response.
steps:
- name: Set the value
id: step_one
run: |
echo 'JSON_RESPONSE<<EOF' >> $GITHUB_ENV
curl https://httpbin.org/json >> $GITHUB_ENV
echo 'EOF' >> $GITHUB_ENV
Adding a system path
echo "{path}" >> $GITHUB_PATH
Prepends a directory to the system PATH
variable and makes it available to all subsequent actions in the current job; the currently running action cannot access the updated path variable. To see the currently defined paths for your job, you can use echo "$PATH"
in a step or an action.
Example
This example demonstrates how to add the user $HOME/.local/bin
directory to PATH
:
echo "$HOME/.local/bin" >> $GITHUB_PATH