The new .stream() API allows the client to consume streaming responses from the WIP streaming callable functions in Firebase Functions Node.js SDK.
When client makes a request to the callable function w/ header Accept: text/event-stream, the callable function responds with response chunks in Server-Sent Event format.
The sdk changes here abstracts over the wire-protocol by parsing the response chunks and returning an instance of a AsyncIterable to consume to data:
import { getFunctions, httpsCallable } from "firebase/functions";
const functions = getFunctions();
const generateText = httpsCallable(functions, 'generateText');
const resp = await generateText.stream(
{ text: 'What is your favorite Firebase service and why?' },
{ signal: AbortSignal.timeout(60_000) },
);
try {
for await (const message of resp.stream) {
console.log(message); // prints "foo", "bar"
}
console.log(await resp.data) // prints "foo bar"
} catch (e) {
// FirebaseError(code='cancelled', message='Request was cancelled.');
console.error(e)
}
