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API

The API block connects your workflow to external services through HTTP requests. Supports GET, POST, PUT, DELETE, and PATCH methods for interacting with REST APIs.

API Block

Configuration Options

URL

The endpoint URL for the API request. This can be:

  • A static URL entered directly in the block
  • A dynamic URL connected from another block's output
  • A URL with path parameters

Method

Select the HTTP method for your request:

  • GET: Retrieve data from the server
  • POST: Send data to the server to create a resource
  • PUT: Update an existing resource on the server
  • DELETE: Remove a resource from the server
  • PATCH: Partially update an existing resource

Query Parameters

Define key-value pairs that will be appended to the URL as query parameters. For example:

Key: apiKey
Value: your_api_key_here

Key: limit
Value: 10

These would be added to the URL as ?apiKey=your_api_key_here&limit=10.

Headers

Configure HTTP headers for your request. Common headers include:

Key: Content-Type
Value: application/json

Key: Authorization
Value: Bearer your_token_here

Request Body

For methods that support a request body (POST, PUT, PATCH), you can define the data to send. The body can be:

  • JSON data entered directly in the block
  • Data connected from another block's output
  • Dynamically generated during workflow execution

Accessing Results

After an API request completes, you can access its outputs:

  • <api.data>: The response body data from the API
  • <api.status>: HTTP status code (200, 404, 500, etc.)
  • <api.headers>: Response headers from the server
  • <api.error>: Error details if the request failed

Advanced Features

Dynamic URL Construction

Build URLs dynamically using variables from previous blocks:

// In a Function block before the API
const userId = <start.userId>;
const apiUrl = `https://api.example.com/users/${userId}/profile`;

Request Retries

The API block automatically handles:

  • Network timeouts with exponential backoff
  • Rate limit responses (429 status codes)
  • Server errors (5xx status codes) with retry logic
  • Connection failures with reconnection attempts

Response Validation

Validate API responses before processing:

// In a Function block after the API
if (<api.status> === 200) {
  const data = <api.data>;
  // Process successful response
} else {
  // Handle error response
  console.error(`API Error: ${<api.status>}`);
}

Outputs

  • <api.data>: Response body data from the API
  • <api.status>: HTTP status code
  • <api.headers>: Response headers
  • <api.error>: Error details if request failed

Example Use Cases

Fetch User Profile Data - Retrieve user information from external service

Function (Build ID) → API (GET /users/{id}) → Function (Format) → Response

Payment Processing - Process payment through Stripe API

Function (Validate) → API (Stripe) → Condition (Success) → Supabase (Update)

Best Practices

  • Use environment variables for sensitive data: Don't hardcode API keys or credentials
  • Handle errors gracefully: Connect error handling logic for failed requests
  • Validate responses: Check status codes and response formats before processing data
  • Respect rate limits: Be mindful of API rate limits and implement appropriate throttling
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