Merge pull request #444 from olsaki/devel

Add docker_login module

cloud/docker/docker_login.py

@@ -0,0 +1,259 @@
+#!/usr/bin/python
+#
+
+# (c) 2015, Olaf Kilian <olaf.kilian@symanex.com>
+#
+# This file is part of Ansible
+#
+# This module is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This software is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this software.  If not, see <http://www.gnu.org/licenses/>.
+
+######################################################################
+
+DOCUMENTATION = '''
+---
+module: docker_login
+author: Olaf Kilian
+version_added: "2.0"
+short_description: Manage Docker registry logins
+description:
+     - Ansible version of the "docker login" CLI command.
+     - This module allows you to login to a Docker registry without directly pulling an image or performing any other actions.
+     - It will write your login credentials to your local .dockercfg file that is compatible to the Docker CLI client as well as docker-py and all other Docker related modules that are based on docker-py.
+options:
+  registry:
+    description:
+       - URL of the registry, defaults to: https://index.docker.io/v1/
+    required: false
+    default: https://index.docker.io/v1/
+  username:
+    description:
+       - The username for the registry account
+    required: true
+  password:
+    description:
+       - The plaintext password for the registry account
+    required: true
+  email:
+    description:
+       - The email address for the registry account. Note that private registries usually don't need this, but if you want to log into your Docker Hub account (default behaviour) you need to specify this in order to be able to log in.
+    required: false
+    default: None
+  reauth:
+    description:
+       - Whether refresh existing authentication on the Docker server (boolean)
+    required: false
+    default: false
+  dockercfg_path:
+    description:
+       - Use a custom path for the .dockercfg file
+    required: false
+    default: ~/.docker/config.json
+  docker_url:
+    descriptions:
+       - Refers to the protocol+hostname+port where the Docker server is hosted
+    required: false
+    default: unix://var/run/docker.sock
+  timeout:
+    description:
+       - The HTTP request timeout in seconds
+    required: false
+    default: 600
+
+requirements: [ "python >= 2.6", "docker-py >= 1.1.0" ]
+'''
+
+EXAMPLES = '''
+Login to a Docker registry without performing any other action. Make sure that the user you are using is either in the docker group which owns the Docker socket or use sudo to perform login actions:
+
+- name: login to DockerHub remote registry using your account
+  docker_login:
+    username: docker
+    password: rekcod
+    email: docker@docker.io
+
+- name: login to private Docker remote registry and force reauthentification
+  docker_login:
+    registry: your.private.registry.io
+    username: yourself
+    password: secrets3
+    reauth: yes
+
+- name: login to DockerHub remote registry using a custom dockercfg file location
+  docker_login:
+    username: docker
+    password: rekcod
+    email: docker@docker.io
+    dockercfg_path: /tmp/.mydockercfg
+
+'''
+
+import os.path
+import json
+import base64
+from urlparse import urlparse
+from distutils.version import StrictVersion
+
+try:
+    import docker.client
+    from docker.errors import APIError as DockerAPIError
+    has_lib_docker = True
+    if StrictVersion(docker.__version__) >= StrictVersion("1.1.0"):
+        has_correct_lib_docker_version = True
+    else:
+        has_correct_lib_docker_version = False
+except ImportError, e:
+    has_lib_docker = False
+
+try:
+    from requests.exceptions import *
+    has_lib_requests_execeptions = True
+except ImportError, e:
+    has_lib_requests_execeptions = False
+
+class DockerLoginManager:
+
+    def __init__(self, module):
+
+        self.module = module
+        self.registry = self.module.params.get('registry')
+        self.username = self.module.params.get('username')
+        self.password = self.module.params.get('password')
+        self.email = self.module.params.get('email')
+        self.reauth = self.module.params.get('reauth')
+        self.dockercfg_path = os.path.expanduser(self.module.params.get('dockercfg_path'))
+
+        docker_url = urlparse(module.params.get('docker_url'))
+        self.client = docker.Client(base_url=docker_url.geturl(), timeout=module.params.get('timeout'))
+
+        self.changed = False
+        self.response = False
+        self.log = list()
+
+    def login(self):
+
+        if self.reauth:
+            self.log.append("Enforcing reauthentification")
+
+        # Connect to registry and login if not already logged in or reauth is enforced.
+        try:
+            self.response = self.client.login(
+                self.username,
+                password=self.password,
+                email=self.email,
+                registry=self.registry,
+                reauth=self.reauth,
+                dockercfg_path=self.dockercfg_path
+            )
+        except DockerAPIError as e:
+            self.module.fail_json(msg="Docker API Error: %s" % e.explanation)
+        except Exception as e:
+            self.module.fail_json(msg="failed to login to the remote registry", error=repr(e))
+
+        # Get status from registry response.
+        if self.response.has_key("Status"):
+            self.log.append(self.response["Status"])
+
+        # Update the dockercfg if not in check mode.
+        if not self.module.check_mode:
+            self.update_dockercfg()
+
+    # This is what the underlaying docker-py unfortunately doesn't do (yet).
+    def update_dockercfg(self):
+
+        # Create dockercfg file if it does not exist.
+        if not os.path.exists(self.dockercfg_path):
+            dockercfg_path_dir = os.path.dirname(self.dockercfg_path)
+            if not os.path.exists(dockercfg_path_dir):
+                os.makedirs(dockercfg_path_dir)
+            open(self.dockercfg_path, "w")
+            self.log.append("Created new Docker config file at %s" % self.dockercfg_path)
+        else:
+            self.log.append("Found existing Docker config file at %s" % self.dockercfg_path)
+
+        # Build a dict for the existing dockercfg.
+        try:
+            docker_config = json.load(open(self.dockercfg_path, "r"))
+        except ValueError:
+            docker_config = dict()
+        if not docker_config.has_key("auths"):
+            docker_config["auths"] = dict()
+        if not docker_config["auths"].has_key(self.registry):
+            docker_config["auths"][self.registry] = dict()
+
+        # Calculate docker credentials based on current parameters.
+        new_docker_config = dict(
+            auth  = base64.b64encode(self.username + b':' + self.password),
+            email = self.email
+        )
+
+        # Update config if persisted credentials differ from current credentials.
+        if new_docker_config != docker_config["auths"][self.registry]:
+            docker_config["auths"][self.registry] = new_docker_config
+            try:
+                json.dump(docker_config, open(self.dockercfg_path, "w"), indent=4, sort_keys=True)
+            except Exception as e:
+                self.module.fail_json(msg="failed to write auth details to file", error=repr(e))
+            self.log.append("Updated Docker config with new credentials.")
+            self.changed = True
+
+    # Compatible to docker-py auth.decode_docker_auth()
+    def encode_docker_auth(self, auth):
+        s = base64.b64decode(auth)
+        login, pwd = s.split(b':', 1)
+        return login.decode('ascii'), pwd.decode('ascii')
+
+    def get_msg(self):
+        return ". ".join(self.log)
+
+    def has_changed(self):
+        return self.changed
+
+def main():
+
+    module = AnsibleModule(
+        argument_spec = dict(
+            registry        = dict(required=False, default='https://index.docker.io/v1/'),
+            username        = dict(required=True),
+            password        = dict(required=True, no_log=True),
+            email           = dict(required=False, default=None),
+            reauth          = dict(required=False, default=False, type='bool'),
+            dockercfg_path  = dict(required=False, default='~/.docker/config.json'),
+            docker_url      = dict(default='unix://var/run/docker.sock'),
+            timeout         = dict(default=10, type='int')
+        ),
+        supports_check_mode=True
+    )
+
+    if not has_lib_docker:
+        module.fail_json(msg="python library docker-py required: pip install docker-py>=1.1.0")
+
+    if not has_correct_lib_docker_version:
+        module.fail_json(msg="your version of docker-py is outdated: pip install docker-py>=1.1.0")
+
+    if not has_lib_requests_execeptions:
+        module.fail_json(msg="python library requests required: pip install requests")
+
+    try:
+        manager = DockerLoginManager(module)
+        manager.login()
+        module.exit_json(changed=manager.has_changed(), msg=manager.get_msg())
+
+    except Exception as e:
+        module.fail_json(msg="Module execution has failed due to an unexpected error", error=repr(e))
+
+# import module snippets
+from ansible.module_utils.basic import *
+
+if __name__ == '__main__':
+    main()