Dockerode: TypeError: Cannot read property 'Promise' of undefined

[hyperlink]

Node: 6.9.4
dockerode: 2.3.3

/Users/hyperlink/dev/temp/node_modules/dockerode/lib/docker.js:24
  this.modem.Promise = opts.Promise || global.Promise;
                           ^

TypeError: Cannot read property 'Promise' of undefined
    at new Docker (/Users/hyperlink/dev/temp/node_modules/dockerode/lib/docker.js:24:28)
    at Object.<anonymous> (/Users/hyperlink/dev/temp/dockerode.js:2:10)
    at Module._compile (module.js:570:32)
    at Object.Module._extensions..js (module.js:579:10)
    at Module.load (module.js:487:32)
    at tryModuleLoad (module.js:446:12)
    at Function.Module._load (module.js:438:3)
    at Module.runMain (module.js:604:10)
    at run (bootstrap_node.js:394:7)
    at startup (bootstrap_node.js:149:9)

[knight42]

Uh... at present you have to pass an object to Docker(), i.e:

docker = new Docker({})

@apocas Perhaps we should handle the case that if opts is undefined:

opts =  opts || {}
this.modem = new Modem(opts);
this.modem.Promise = opts.Promise || global.Promise;

[tanuck]

This has also broken the instantiation of docker-modem.

By doing:
docker = new Docker({}) or docker = new Docker({Promise: require("bluebird")})

When reaching this line this.modem = new Modem(opts); on line 23 of lib/docker.js, opts is a non null object which prevents defaultOpts() in the docker-modem constructor ever being called. This is now broken for anyone relying on docker-modem to read the DOCKER_* env variables for the connection to the docker host.

---

On another note, this is a breaking change for anyone who previously promisifed the prototypes with bluebird.promisifyAll. Bluebird throws when it encounters methods with Async already in the name.

Definitely not a patch release in it's current state!

Cheers

[ThomWright]

So would this be a better fix?

this.modem = new Modem(opts);
this.modem.Promise = opts && opts.Promise || global.Promise;

Doesn't fix the problem with runAsync making bluebird.promisifyAll blow up, but that's a another issue.

By the way, what's the reason behind doing this.modem.Promise rather than just this.Promise?

[apocas]

https://github.com/apocas/dockerode/commit/014f5be40437fc2576f910e4dc438ef05180c464

v2.3.4 just published fixes this.

@ThomWright modem is the object that's everywhere. Example: https://github.com/apocas/dockerode/blob/master/lib/container.js#L65

[apocas]

@ThomWright run now also features a promise interface, you need to manually promisify it.

Example in the readme: https://github.com/apocas/dockerode/blob/master/README.md#equivalent-of-docker-run-in-dockerode

[tanuck]

@apocas this doesn't solve the first problem I mentioned above. Should I open another issue?

Cheers

[apocas]

@tanuck I already have a fix for it, but yes please so we can follow up there.