Create an action

• You have the following:
  • A test web server that has access to the Internet, so that it can receive POST requests from Shopify Flow
  • A test app that works with the test web server
  • A development store that has Shopify Flow and the test app installed

To give your Flow action a meaningful name, use the following guidelines:

• Use a present-tense verb + object acted on format. For example, Place auction bid.
• Use sentence case.
• Don't use punctuation.
• Separate words using spaces.

Use the Shopify CLI to generate a new extension:

1. Navigate to your app directory.
2. Run the following command:

1. Select the Flow Action as the type of extension.
2. Provide a meaningful name for your extension.
   

After you've followed the prompts, Shopify CLI generates the extension’s file representation in your app's /extensions directory and gives you a success message. You can then go into your app's /extensions directory and start editing your new extension.

The file structure of your extension should look like the following:

To learn more about the extensions file structure, refer to App structure and the documentation for your extension type.

1. In your Partner Dashboard, click Apps.
2. Select the app that you want to add your Shopify Flow action to.
3. Click Extensions, then click Create or Create extension.
4. Under the Flow tab, click Flow/Actions.
5. In the Extension name field, name your action, such as Place auction bid. This name is used only for internal purposes.
6. Enter a title and description for the action. In the Action Preview area, you can see how the title and action display to merchants when they're choosing actions in Shopify Flow.
7. Enter the URL for the action execution endpoint that you created. Shopify Flow sends the action's JSON payload to this endpoint when it's about to execute your action.

In this section you'll use the default action template and update it to be a functional extension example. Once you have generated a Flow extension using Shopify CLI, follow the instructions below:

1. Change the description to Place a bid on an auction.
2. Update the extensions.runtime_url to an endpoint where you can receive the runtime request.
3. On the second settings.fields field, update the following values:
   • type to number_decimal
   • key to amount
   • name to Bid Amount
   • Add a description property and set it to The amount of the bid

To build a Shopify Flow action, you need to add a service to your web server to listen for the JSON payload that Shopify Flow sends when the action runs.

Optionally, you can also add the following:

• An endpoint to validate actions
• A custom configuration page, and an endpoint that lets merchants preview your custom configuration page

Add the following API endpoints to your server:

To learn more about the endpoint requirements for your server, refer to Action endpoints.

To learn how to create a custom configuration page, refer to Build a custom configuration page.

Running app dev allows changes made to local files to update the draft version of your Flow task extensions. The draft version is only available in your development store.

1. Navigate to your app directory.
2. Run the following command to start using draft versions of your extension(s):

1. Follow the prompts.

After you've created an action in the Partner Dashboard and added support for it in your web server, you can test the action in Shopify Flow on your development store.

1. In your development store, create a workflow that uses the action. For example, add the trigger that you created in the Triggers guide and this action to a workflow.

2. If you created a custom configuration page, then ensure that the preview displays and that the custom configuration page is accessible.

3. If you added any custom validation, then ensure that it works as expected.

4. Trigger the workflow. For example, in your web server, run the event that sends the trigger information to Shopify Flow.

When the workflow completes, your web server has sent data to Shopify Flow because of the trigger. Shopify Flow has sent this data to a web server that logged the information to its console because of the action.

Use Shopify CLI to deploy your extensions:

1. Navigate to your app directory.
2. Run the following command to start deploying your extension(s):

1. Follow the prompts.

When you receive confirmation that the deploy was successful, your extensions have been released.

For security reasons, make sure that you verify the following elements in each request:

• The POST request's HMAC header (either x-shopify-hmac-sha256 or http-x-shopify-hmac-sha256). The HMAC header should be verified before you process the payload. For more information, refer to Verifying requests.
• The payload handle. This ID should match the handle of the action that you created, and can be retrieved from the payload preview.

• Connect your app to Shopify Flow so that events that occur in your app can trigger workflows.
• Learn how to receive lifecycle events from Shopify Flow about the stores that are using your triggers in enabled workflows.
• Learn more about how to return complex data in a Flow action.