Simulate a failing receiver - DevHelm

The mock reply is what the sender receives after the inbox stores the request. Status is 200–599. Delay is 0–30000 milliseconds. The default is HTTP 200, text/plain, an empty body, and no delay. Use this to force a retry or a client timeout. The capture still happens. Only the reply changes.

Change an existing inbox

import { Devhelm } from "@devhelm/sdk";

const client = new Devhelm({
  token: process.env.DEVHELM_API_TOKEN!,
});

await client.inboxes.update("<inbox-id>", {
  httpResponse: {
    status: 500,
    contentType: "text/plain",
    body: "unavailable",
    delayMs: 5000,
  },
});

Omitted httpResponse fields stay as they are. Set delayMs to 0 and status to 200 to return to a fast success. The same patch over HTTP:

API

curl -X PATCH "https://api.devhelm.io/api/v1/webhook/inboxes/<inbox-id>" \
  -H "Authorization: Bearer $DEVHELM_API_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"httpResponse":{"status":500,"contentType":"text/plain","body":"unavailable","delayMs":5000}}'

Set the reply at create time

export DEVHELM_API_TOKEN=dh_live_xxxxxxxx
devhelm inboxes create \
  --name failing-receiver \
  --response-status 500 \
  --response-body unavailable \
  --response-content-type text/plain \
  --response-delay-ms 5000 \
  -o json

devhelm inboxes update changes name, status, CORS, retention, and max events. It does not change the mock reply. Use the SDK or the PATCH above for an inbox that already exists.

Next steps

Assert in a test

Wait for the request your retry logic sends.

How capture works

What is stored, and when a sender is dropped.