Can't pass host device or volume to container if host path contains colon

[kavefish]

Steps to reproduce

1. Create a host path containing a colon

sudo mkdir /test:dir

2. Use "recommended dictionary notation" to pass volume to container

import docker
client = docker.from_env()
vols={'/test:dir': {'bind': '/test'}}
client.containers.create("ubuntu:latest", volumes=vols)

Error

APIError: 500 Server Error: Internal Server Error ("invalid volume specification: '/test:dir:/testdir:rw'")

Stack trace

APIError                                  Traceback (most recent call last)                                                                                       <ipython-input-11-9017b6f19e04> in <module>()                                                                                                                            
----> 1 client.containers.create("ubuntu:latest", volumes=vols)                                                                                                          
                                                                                                                                                                         
/home/kavefish/Documents/devel/docker-py-bug/docker/models/containers.pyc in create(self, image, command, **kwargs)                                                      
    822         kwargs['version'] = self.client.api._version                                                                                                             
    823         create_kwargs = _create_container_args(kwargs)                                                                                                           
--> 824         resp = self.client.api.create_container(**create_kwargs)
    825         return self.get(resp['Id'])
    826

/home/kavefish/Documents/devel/docker-py-bug/docker/api/container.pyc in create_container(self, image, command, hostname, user, detach, stdin_open, tty, ports, environm$
nt, volumes, network_disabled, name, entrypoint, working_dir, domainname, host_config, mac_address, labels, stop_signal, networking_config, healthcheck, stop_timeout, r$
ntime)
    408             stop_timeout, runtime
    409         )
--> 410         return self.create_container_from_config(config, name)
    411
    412     def create_container_config(self, *args, **kwargs):

/home/kavefish/Documents/devel/docker-py-bug/docker/api/container.pyc in create_container_from_config(self, config, name)
    419         }
    420         res = self._post_json(u, data=config, params=params)
--> 421         return self._result(res, True)
    422
    423     def create_host_config(self, *args, **kwargs):

/home/kavefish/Documents/devel/docker-py-bug/docker/api/client.pyc in _result(self, response, json, binary)
    229     def _result(self, response, json=False, binary=False):
    230         assert not (json and binary)
--> 231         self._raise_for_status(response)
    232
    233         if json:

/home/kavefish/Documents/devel/docker-py-bug/docker/api/client.pyc in _raise_for_status(self, response)
    225             response.raise_for_status()
    226         except requests.exceptions.HTTPError as e:
--> 227             raise create_api_error_from_http_exception(e)
    228
    229     def _result(self, response, json=False, binary=False):

/home/kavefish/Documents/devel/docker-py-bug/docker/errors.pyc in create_api_error_from_http_exception(e)
     29         else:
     30             cls = NotFound
---> 31     raise cls(e, response=response, explanation=explanation)

APIError: 500 Server Error: Internal Server Error ("invalid volume specification: '/test:dir:/testdir:rw'")

Environment

docker-py: 3.3.0
Python: 2.7.15rc1
engine: 17.12.1-ce
Ubuntu 18.04

[kavefish]

The same error occurs if the colon appears in the bind mount path for the container, e.g.

import docker
client = docker.from_env()
vols={'/somedir': {'bind': '/test:path'}}
client.containers.create("ubuntu:latest", volumes=vols)

[thaJeztah]

The volumes format is known to have some limitations, because it uses a colon as separator between options; does it work if you useMount option instead? https://docker-py.readthedocs.io/en/stable/api.html#docker.types.Mount

Looks like you want to do a bind-mount, in which case you have to set type to "bind"

[kavefish]

@thaJeztah, thanks very much for the suggestion.

Yes, I do want a bind mount. I thought I was specifying a bind mount by using the dictionary notation which specifies "bind" in the dictionary.

Is the recommendation that the low-level API is required to accomplish a bind mount with a colon in the path?

[thaJeztah]

I'll have to defer that one to @shin-, I'm not very familiar with the docker-py sdk (or python, for that matter) 😊

[shin-]

Sorry for the confusion on the earlier thread.

1. mounts and binds are 2 different things, as explained here (in the context of the CLI). mounts is more modern and a better choice 99% of the time.
2. Because of the way the binds API was designed, {'/test:dir': {'bind': '/test'}} has to be transformed into ['test:dir:/test'], which the daemon fails to parse (as it expects the colon to be a path separator). This is not a SDK issue. (See here for the Docker daemon API)
3. As @thaJeztah pointed out, the correct approach to this problem is to use mounts instead

import docker
c = docker.from_env()
mnt = docker.types.Mount(type='bind', source='/tmp/colon:colon/', target='/colon')
ctnr = c.containers.create('busybox', mounts=[mnt]) # <Container: 38869806cb>

HTH

[ijc]

Closing since this seems to have been answered.