Real-Time Telemetry (SSE)

4. Real-Time Telemetry & Server-Sent Events (SSE)

Streaming Protocol (/v1/stream/{did})

The SSE endpoint streams stages as they execute inside the Rust runtime:

GET /v1/stream/did:web:identity.foundation HTTP/1.1
Host: did.is
Accept: text/event-stream

Stream event lifecycle:

1. event: stage: Emitted on completion of each trace stage (startedUs, durationUs, status: PASS|FAIL).
2. event: result: Emitted once with the full EnrichedResolution payload.
3. event: error: Emitted if resolution halts prematurely (carries RFC 9457 problem JSON).
4. event: done: Emits {} and closes the stream.

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Consuming SSE in TypeScript

import { DidisClient } from "@didis/client";

const didis = new DidisClient();

async function streamDemo() {
  const iterator = didis.stream("did:web:identity.foundation", { noCache: true });

  for await (const event of iterator) {
    if (event.event === "stage") {
      const { stage, status, durationUs } = event.data;
      console.log(`⏱️ [${status}] ${stage} (${durationUs} µs)`);
    } else if (event.event === "result") {
      console.log(`\n🎉 Resolution Complete: ${event.data.verdict.headline}`);
    } else if (event.event === "error") {
      console.error(`❌ Stream Failed: ${event.data.title}`);
    }
  }
}

streamDemo();

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Consuming SSE in Python

from didis import DidisClient

with DidisClient() as client:
    for event_type, payload in client.stream("did:web:identity.foundation", no_cache=True):
        if event_type == "stage":
            print(f"⏱️ [{payload['status']}] {payload['stage']} ({payload['durationUs']} µs)")
        elif event_type == "result":
            print(f"\n🎉 Resolution Complete: {payload['verdict']['headline']}")
        elif event_type == "error":
            print(f"❌ Error: {payload['title']}")

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