Handle container failures

In this section, you will learn how to handle container failures in app-compose.

When a container fails to start, you can detect this and take action.

Example

const unstableService = createContainer({
  id: 'unstable-service',
  domain: 'backend',
  start: () => {
    throw new Error('Service failed to start');
  },
});

const myFeature = createContainer({
  id: 'feature',
  domain: 'frontend',
  dependencies: [unstableService],
  start: () => ({ api: {} }),
});

const { up } = await compose({
  stages: [['stage-name', [myFeature]]],
});

await up({
  onContainerFail: ({ container, error, stageId }) => {
    // for example, sending the error
    // to an error tracking service.
    console.log({
      stageId,
      container,
      msg: error.message,
    });
  },
});

When you run this code, you should see the following output in the console:

{
  "stageId": "stage-name",
  "container": {
    "id": "unstable-service",
    "domain": "backend"
  },
  "msg": "Service failed to start"
}

Try it