How to Set Up a Selection Flow?

Selection flows in Fastn allow you to fetch dynamic data (such as lists of items, projects, or files) that can then be displayed as selectable options inside configuration flows. These are reusable across widgets or connectors wherever a dynamic selection is required.

1. Create a Selection Flow

• Go to the Widgets section in Fastn.

• Click the arrow next to the Add Widget button (top-right corner).

• Select Add Selection Flow.

• Enter a name for your flow and click Build.

This will create a configuration flow that allows you to define the logic for your selection data source.

In this guide, we’ll build a selection flow using the Google Cloud Storage connector and its Get Buckets action.

2. Add a Connector Action Step

Inside your new flow, add a step and choose Connector Action.

This is where you define which connector and which specific endpoint will supply data to your selection flow.

1. Under Group Type, select Fastn Connectors.

   • You can also choose Workspace Connectors if you’ve built custom connectors in your workspace.

2. Under Connector, select Google Cloud Storage.

3. Under Endpoint, select Get Buckets.

Your step now represents the request that will fetch a list of storage buckets from Google Cloud Storage.

3. Configure the Connector Action

After selecting the endpoint, click Next. You’ll now see the Connection Configuration section.

Here you can decide how your widget or flow connects to an account:

• Fixed Connection: Uses a specific account that you connect here (e.g., your own Google Cloud Storage account).

• Dynamic Connection: Allows multiple users to connect their own accounts dynamically through widgets.

4. Define the Configuration Parameters

Once your connection is set, you’ll see the Configure section. This section displays the endpoint URL and the fields you can map.

For the Google Cloud Storage – Get Buckets endpoint, for example, you’ll see:

5. Test the Selection Flow

Next, open the Test section.

Here you can:

• View the Headers and Input fields used in your connector request.

• See the Tenant ID associated with your workspace or environment.

• Run a Test to verify that your selection flow returns the expected data (e.g., a list of buckets).

If successful, you’ll see the response data in the output preview.

6. Add a Final Step

Once you’ve confirmed the connector response, you can add any follow-up step to process or format the data.

For instance, in this use case,

• Add an Advanced Action to transform the output.

• Add a Loop step to iterate over the items returned (e.g., each bucket).

• Or simply return a Success Message as an object confirming completion:

Str "GCS buckets' fetching successful"

This final output will serve as the data source for your selection dropdown in configuration flows.

7. Using the Selection Flow in Configuration Flows

After saving, your newly created flow will appear in:

• Workspace Selection Flows (if created within your workspace), or

• Community Selection Flows (if shared publicly).

For example, in your GCS Configuration Flow, when you open the selection dropdown for a dynamic input, you’ll see “GCS – Get Buckets” listed as an available selection source. You can then enable pagination, apply limits, or transform the results based on your configuration.

Your selection flow is now ready and can be reused across configuration flows wherever dynamic data selection is required.

Example Scenarios

• Populate dropdowns with live data from connectors (e.g., list of buckets, projects, or files).

• Handle large datasets using pagination and limit controls.

• Provide a seamless experience for users to select external data dynamically from widgets.