Help using docker.service.update()

[lhenry7]

Hi, trying to understand how to use this method? The docker api needs version in query string and Spec in Post body. Do you have any examples? I'm not a native js programmer and I'm not sure how I should be calling: var version = service.data["Version"]["Index"]; service.data.Spec.Mode.Replicated.Replicas=update_count; service.update({version: version}) .catch(error => console.log(error));

gives { Error: (HTTP code 400) unexpected - rpc error: code = InvalidArgument desc = TaskSpec: missing runtime at /etc/chef/compose-stacks/node_modules/docker-modem/lib/modem.js:239:17 at getCause (/etc/chef/compose-stacks/node_modules/docker-modem/lib/modem.js:269:7) at Modem.buildPayload (/etc/chef/compose-stacks/node_modules/docker-modem/lib/modem.js:238:5) at IncomingMessage. (/etc/chef/compose-stacks/node_modules/docker-modem/lib/modem.js:214:14) at emitNone (events.js:111:20) at IncomingMessage.emit (events.js:208:7) at endReadableNT (_stream_readable.js:1055:12) at _combinedTickCallback (internal/process/next_tick.js:138:11) at process._tickCallback (internal/process/next_tick.js:180:9) reason: undefined, statusCode: 400, json: { message: 'rpc error: code = InvalidArgument desc = TaskSpec: missing runtime' } }

P.S. - Just saw this, seems related: (https://github.com/docker-java/docker-java/issues/958) does the api version need to be updated someplace?

[herlon214]

This example is working on my machine:

// Load docker etc etc

const scale = (service, replicas) => {
  const data = service.data.Spec
  data.version = service.data.Version.Index
  data.Mode.Replicated.Replicas = replicas

  return service.update(data)
}

scale(yourServiceObject, 5)

[lhenry7]

Thanks @herlon214, I see why your code works. Not being a native JS programmer was tripping me up!