Workflow commands for GitHub Actions

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}"

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:

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.

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 steps running next in a job. The step that creates or updates the environment variable does not have access to the new value, but all subsequent steps 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