Send streaming response

Stream event data back to the caller while your API Endpoint workflow runs. This is useful when you want to show progress for long tasks (like imports, file generation, or AI responses).

How it works

Instead of waiting until your workflow is finished, WeWeb can send updates as they happen.

Here’s what that means in practice:

• The first time Send streaming response runs, WeWeb starts a “live” response.
• Each next Send streaming response adds another message to that same response.
• Your app can read those messages and update the UI (for example show progress, or display new text as it arrives).

What “streaming” means

Streaming is just a way of keeping the connection open so WeWeb can send multiple updates. This uses a standard called Server‑Sent Events (SSE).

Configuration

Setting	What it does
Event Data	The data to send as the next message in the stream.

Using the stream in your interface

To receive streaming messages in an interface workflow, you need to call your endpoint and enable stream handling:

1. In Interface, create a workflow (for example “On click”).
2. Click + Add an action, then go to Workflows → API and select your API Endpoint.
3. Open the action’s Advanced section and enable Handle stream.
4. Run the workflow.

While the workflow is running, you can use the streaming data in bindings from that action:

• stream.chunk — The latest message received
• stream.chunks — All messages received so far

Example: stream progress updates

In your API Endpoint workflow, you can send progress messages as you go:

1. Start your long task (for example, looping through rows to import)
2. After each step, add Send streaming response with Event Data like:
   • { "step": "import", "done": 5, "total": 20 }
3. In your interface, bind stream.chunk to a progress UI (like a text label or progress bar)

Common pitfalls

Nothing shows up in the interface

• Make sure you enabled Handle stream on the API Endpoint action you added from Workflows → API.
• Make sure your API Endpoint workflow actually runs Send streaming response at least once.

CONTINUE LEARNING

Learn how to call endpoints from your interface workflows.

Executing from interface workflows →