deis.py

#!/usr/bin/env python
"""
This Deis command-line client issues API calls to a Deis controller.

Usage: deis <command> [--formation <formation>] [<args>...]

Auth commands::

  register      register a new user with a controller
  login         login to a controller
  logout        logout from the current controller

Shortcut commands::

  create        create a new container formation
  scale         scale container types (web=2, worker=1)
  logs          print most recent logs for the formation
  open          open a URL for the formation in a browser
  info          print a representation of the formation
  converge      force-converge all nodes in the formation
  calculate     recalculate and update the formation databag
  destroy       destroy a container formation

Subcommands, use ``deis help [subcommand]`` to learn more::

  formations    manage container formations
  layers        manage layers of nodes
  nodes         manage nodes of all types
  containers    manage runtime containers

  providers     manage cloud provider credentials
  flavors       manage node flavors on a provider
  keys          manage ssh keys

  config        manage environment variables for a formation
  builds        manage git-push or docker builds
  releases      manage a formation's release history

Use ``git push deis master`` to deploy to a formation.

"""

from cookielib import MozillaCookieJar
from getpass import getpass
import glob
import json
import os.path
import random
import re
import subprocess
import sys
import time
import urlparse
import webbrowser
import yaml

from docopt import docopt
from docopt import DocoptExit
import requests

__version__ = '0.0.5'


class Session(requests.Session):
    """
    Session for making API requests and interacting with the filesystem
    """

    def __init__(self):
        super(Session, self).__init__()
        self.trust_env = False
        cookie_file = os.path.expanduser('~/.deis/cookies.txt')
        cookie_dir = os.path.dirname(cookie_file)
        self.cookies = MozillaCookieJar(cookie_file)
        # Create the $HOME/.deis dir if it doesn't exist
        if not os.path.isdir(cookie_dir):
            os.mkdir(cookie_dir, 0700)
        # Load existing cookies if the cookies.txt exists
        if os.path.isfile(cookie_file):
            self.cookies.load()
            self.cookies.clear_expired_cookies()

    def clear(self, domain):
        """Clear cookies for the specified domain."""
        try:
            self.cookies.clear(domain)
            self.cookies.save()
        except KeyError:
            pass

    def git_root(self):
        """
        Return the absolute path from the git repository root

        If no git repository exists, raise an EnvironmentError
        """
        try:
            git_root = subprocess.check_output(
                ['git', 'rev-parse', '--show-toplevel'],
                stderr=subprocess.PIPE).strip('\n')
        except subprocess.CalledProcessError:
            raise EnvironmentError('Current directory is not a git repository')
        return git_root

    def get_formation(self):
        """
        Return the formation name for the current directory

        The formation is determined by parsing `git remote -v` output.
        If no formation is found, raise an EnvironmentError.
        """
        git_root = self.git_root()
        # try to match a deis remote
        remotes = subprocess.check_output(['git', 'remote', '-v'],
                                          cwd=git_root)
        m = re.match(r'^deis\W+(?P<url>\S+)\W+\(', remotes, re.MULTILINE)
        if not m:
            raise EnvironmentError(
                'Could not find deis remote in `git remote -v`')
        url = m.groupdict()['url']
        m = re.match('\S+:(?P<formation>[a-z0-9-]+)(.git)?', url)
        if not m:
            raise EnvironmentError("Could not parse: {url}".format(**locals()))
        return m.groupdict()['formation']

    formation = property(get_formation)

    def request(self, *args, **kwargs):
        """
        Issue an HTTP request with proper cookie handling including
        `Django CSRF tokens <https://docs.djangoproject.com/en/dev/ref/contrib/csrf/>`
        """
        for cookie in self.cookies:
            if cookie.name == 'csrftoken':
                if 'headers' in kwargs:
                    kwargs['headers']['X-CSRFToken'] = cookie.value
                else:
                    kwargs['headers'] = {'X-CSRFToken': cookie.value}
                break
        response = super(Session, self).request(*args, **kwargs)
        self.cookies.save()
        return response


class Settings(dict):
    """
    Settings backed by a file in the user's home directory

    On init, settings are loaded from ~/.deis/client.yaml
    """

    def __init__(self):
        path = os.path.expanduser('~/.deis')
        if not os.path.exists(path):
            os.mkdir(path)
        self._path = os.path.join(path, 'client.yaml')
        if not os.path.exists(self._path):
            with open(self._path, 'w') as f:
                f.write(yaml.safe_dump({}))
        # load initial settings
        self.load()

    def load(self):
        """
        Deserialize and load settings from the filesystem
        """
        with open(self._path) as f:
            data = f.read()
        settings = yaml.safe_load(data)
        self.update(settings)
        return settings

    def save(self):
        """
        Serialize and save settings to the filesystem
        """
        data = yaml.safe_dump(dict(self))
        with open(self._path, 'w') as f:
            f.write(data)
        return data


def dictify(args):
    """Converts a list of key=val strings into a python dict.

    >>> dictify(['MONGODB_URL=http://mongolabs.com/test', 'scale=5'])
    {'MONGODB_URL': 'http://mongolabs.com/test', 'scale': 5}
    """
    data = {}
    for arg in args:
        try:
            var, val = arg.split('=')
        except ValueError:
            raise DocoptExit()
        # Try to coerce the value to an int since that's a common use case
        try:
            data[var] = int(val)
        except ValueError:
            data[var] = val
    return data


def trim(docstring):
    """
    Function to trim whitespace from docstring

    c/o PEP 257 Docstring Conventions
    <http://www.python.org/dev/peps/pep-0257/>
    """
    if not docstring:
        return ''
    # Convert tabs to spaces (following the normal Python rules)
    # and split into a list of lines:
    lines = docstring.expandtabs().splitlines()
    # Determine minimum indentation (first line doesn't count):
    indent = sys.maxint
    for line in lines[1:]:
        stripped = line.lstrip()
        if stripped:
            indent = min(indent, len(line) - len(stripped))
    # Remove indentation (first line is special):
    trimmed = [lines[0].strip()]
    if indent < sys.maxint:
        for line in lines[1:]:
            trimmed.append(line[indent:].rstrip())
    # Strip off trailing and leading blank lines:
    while trimmed and not trimmed[-1]:
        trimmed.pop()
    while trimmed and not trimmed[0]:
        trimmed.pop(0)
    # Return a single string:
    return '\n'.join(trimmed)


class DeisClient(object):
    """
    A client which interacts with a Deis controller.
    """

    def __init__(self):
        self._session = Session()
        self._settings = Settings()

    def _dispatch(self, method, path, body=None,
                  headers={'content-type': 'application/json'}, **kwargs):
        """
        Dispatch an API request to the active Deis controller
        """
        func = getattr(self._session, method.lower())
        controller = self._settings['controller']
        if not controller:
            raise EnvironmentError(
                'No active controller. Use `deis login` or `deis register` to get started.')
        url = urlparse.urljoin(controller, path, **kwargs)
        response = func(url, data=body, headers=headers)
        return response

    def auth_register(self, args):
        """
        Register a new user with a Deis controller

        Usage: deis auth:register <controller> [options]

        Options:

        --username=USERNAME    provide a username for the new account
        --password=PASSWORD    provide a password for the new account
        --email=EMAIL          provide an email address
        """
        controller = args['<controller>']
        username = args.get('--username')
        if not username:
            username = raw_input('username: ')
        password = args.get('--password')
        if not password:
            password = getpass('password: ')
        email = args.get('--email')
        if not email:
            email = raw_input('email: ')
        url = urlparse.urljoin(controller, '/api/auth/register')
        payload = {'username': username, 'password': password, 'email': email}
        response = self._session.post(url, data=payload, allow_redirects=False)
        if response.status_code == requests.codes.created:  # @UndefinedVariable
            self._settings['controller'] = controller
            self._settings.save()
            print("Registered {}".format(username))
            login_args = {'--username': username, '--password': password,
                          '<controller>': controller}
            if self.auth_login(login_args) is False:
                print('Login failed')
                return
            print
            self.keys_add({})
            print
            self.providers_discover({})
            print
            print 'Use `deis create --flavor=ec2-us-east-1` to create a new formation'
        else:
            print('Registration failed', response.content)
            return False

    def auth_login(self, args):
        """
        Login by authenticating against a controller

        Usage: deis auth:login <controller> [--username=<username> --password=<password>]
        """
        controller = args['<controller>']
        username = args.get('--username')
        headers = {}
        if not username:
            username = raw_input('username: ')
        password = args.get('--password')
        if not password:
            password = getpass('password: ')
        url = urlparse.urljoin(controller, '/api/auth/login/')
        payload = {'username': username, 'password': password}
        # clear any cookies for this controller's domain
        self._session.clear(urlparse.urlparse(url).netloc)
        # prime cookies for login
        self._session.get(url, headers=headers)
        # post credentials to the login URL
        response = self._session.post(url, data=payload, allow_redirects=False)
        if response.status_code == requests.codes.found:  # @UndefinedVariable
            self._settings['controller'] = controller
            self._settings.save()
            print("Logged in as {}".format(username))
            return True
        else:
            print('Login failed')
            self._session.cookies.clear()
            self._session.cookies.save()
            return False

    def auth_logout(self, args):
        """
        Logout from a controller and clear the user session

        Usage: deis auth:logout
        """
        controller = self._settings.get('controller')
        if controller:
            self._dispatch('get', '/api/auth/logout/')
        self._session.cookies.clear()
        self._session.cookies.save()
        self._settings['controller'] = None
        self._settings.save()
        print('Logged out')

    def builds(self, args):
        """
        Valid commands for builds:

        builds:list        list build history for a formation
        builds:create      coming soon!

        Use `deis help [command]` to learn more
        """
        return self.builds_list(args)

    def builds_create(self, args):
        """
        Create a new build for a formation

        Usage: deis builds:create - [--formation=<formation>]
        """
        formation = args.get('--formation')
        if not formation:
            formation = self._session.formation
        data = sys.stdin.read()
        # url / sha / slug_size / procfile / checksum
        j = json.loads(data)
        response = self._dispatch('post',
                                  "/api/formations/{}/builds".format(formation),
                                  body=json.dumps(j))
        if response.status_code == requests.codes.created:  # @UndefinedVariable
            print('Build created.')
        else:
            print('Error!', response.text)

    def builds_list(self, args):
        """
        List build history for a formation

        Usage: deis builds:list
        """
        formation = args.get('--formation')
        if not formation:
            formation = self._session.formation
        response = self._dispatch('get', "/api/formations/{}/builds".format(formation))
        if response.status_code == requests.codes.ok:  # @UndefinedVariable
            print("=== {} Builds".format(formation))
            data = response.json()
            for item in data['results']:
                print("{0[uuid]:<23} {0[created]}".format(item))
        else:
            print('Error!', response.text)

    def config(self, args):
        """
        Valid commands for config:

        config:list        list environment variables for a formation
        config:set         set environment variables for a formation
        config:unset       unset environment variables for a formation

        Use `deis help [command]` to learn more
        """
        return self.config_list(args)

    def config_list(self, args):
        """
        List environment variables for a formation

        Usage: deis config:list
        """
        formation = args.get('--formation')
        if not formation:
            formation = self._session.formation
        response = self._dispatch('get', "/api/formations/{}/config".format(formation))
        if response.status_code == requests.codes.ok:  # @UndefinedVariable
            config = response.json()
            values = json.loads(config['values'])
            print("=== {} Config".format(formation))
            items = values.items()
            if len(items) == 0:
                print('No configuration')
                return
            for k, v in values.items():
                print("{k}: {v}".format(**locals()))
        else:
            print('Error!', response.text)

    def config_set(self, args):
        """
        Set environment variables for a formation

        Usage: deis config:set <var>=<value>...
        """
        formation = args.get('--formation')
        if not formation:
            formation = self._session.formation
        body = {'values': json.dumps(dictify(args['<var>=<value>']))}
        response = self._dispatch('post',
                                  "/api/formations/{}/config".format(formation),
                                  json.dumps(body))
        if response.status_code == requests.codes.created:  # @UndefinedVariable
            config = response.json()
            values = json.loads(config['values'])
            print("=== {}".format(formation))
            items = values.items()
            if len(items) == 0:
                print('No configuration')
                return
            for k, v in values.items():
                print("{k}: {v}".format(**locals()))
        else:
            print('Error!', response.text)

    def config_unset(self, args):
        """
        Unset an environment variable for a formation

        Usage: deis config:unset <key>...
        """
        formation = args.get('--formation')
        if not formation:
            formation = self._session.formation
        values = {}
        for k in args.get('<key>'):
            values[k] = None
        body = {'values': json.dumps(values)}
        response = self._dispatch('post',
                                  "/api/formations/{}/config".format(formation),
                                  data=json.dumps(body))
        if response.status_code == requests.codes.created:  # @UndefinedVariable
            config = response.json()
            values = json.loads(config['values'])
            print("=== {}".format(formation))
            items = values.items()
            if len(items) == 0:
                print('No configuration')
                return
            for k, v in values.items():
                print("{k}: {v}".format(**locals()))
        else:
            print('Error!', response.text)

    def containers(self, args):
        """
        Valid commands for containers:

        containers:list        list containers for a formation
        containers:scale       scale a formation's containers (i.e web=4 worker=2)

        Use `deis help [command]` to learn more
        """
        return self.containers_list(args)

    def containers_list(self, args):
        """
        List containers for a formation

        Usage: deis containers:list
        """
        formation = args.get('--formation')
        if not formation:
            formation = self._session.formation
        response = self._dispatch('get',
                                  "/api/formations/{}/containers".format(formation))
        databag = self.formations_calculate({}, quiet=True)
        procfile = databag['release']['build'].get('procfile', {})
        if response.status_code == requests.codes.ok:  # @UndefinedVariable
            data = response.json()
            print("=== {} Containers".format(formation))
            c_map = {}
            for item in data['results']:
                c_map.setdefault(item['type'], []).append(item)
            print
            for c_type in c_map.keys():
                command = procfile.get(c_type, '<none>')
                print("--- {c_type}: `{command}`".format(**locals()))
                for c in c_map[c_type]:
                    print("{type}.{num} up {created} ({node})".format(**c))
                print
        else:
            print('Error!', response.text)

    def containers_scale(self, args):
        """
        Scale containers for a formation

        Example: deis containers:scale web=4 worker=2

        Usage: deis containers:scale <type=num>...
        """
        formation = args.get('--formation')
        if not formation:
            formation = self._session.formation
        body = {}
        for type_num in args.get('<type=num>'):
            typ, count = type_num.split('=')
            body.update({typ: int(count)})
        print('Scaling containers... but first, coffee!')
        before = time.time()
        response = self._dispatch('post',
                                  "/api/formations/{}/scale/containers".format(formation),
                                  json.dumps(body))
        if response.status_code == requests.codes.ok:  # @UndefinedVariable
            print('done in {}s\n'.format(int(time.time() - before)))
            self.containers_list({})
        else:
            print('Error!', response.text)

    def flavors(self, args):
        """
        Valid commands for flavors:

        flavors:create        create a new node flavor
        flavors:info          print information about a node flavor
        flavors:list          list available flavors
        flavors:delete        delete a node flavor

        Use `deis help [command]` to learn more
        """
        return self.flavors_list(args)

    def flavors_create(self, args):
        """
        Create a new node flavor

        Usage: deis flavors:create --id=<id> --provider=<provider> --params=<params> [options]

        Options:

        --params=PARAMS    provider-specific parameters (size, region, zone, etc.)
        --init=INIT        override Ubuntu cloud-init with custom YAML
        """
        body = {'id': args.get('--id'), 'provider': args.get('--provider')}
        fields = ('params', 'init', 'ssh_username', 'ssh_private_key',
                  'ssh_public_key')
        for fld in fields:
            opt = args.get('--' + fld)
            if opt:
                body.update({fld: opt})
        response = self._dispatch('post', '/api/flavors', json.dumps(body))
        if response.status_code == requests.codes.created:  # @UndefinedVariable
            print("{0[id]}".format(response.json()))
        else:
            print('Error!', response.text)

    def flavors_delete(self, args):
        """
        Delete a node flavor

        Usage: deis flavors:delete <id>
        """
        flavor = args.get('<id>')
        response = self._dispatch('delete', "/api/flavors/{}".format(flavor))
        if response.status_code == requests.codes.no_content:  # @UndefinedVariable
            pass
        else:
            print('Error!', response.status_code, response.text)

    def flavors_info(self, args):
        """
        Print information about a node flavor

        Usage: deis flavors:info <flavor>
        """
        flavor = args.get('<flavor>')
        response = self._dispatch('get', "/api/flavors/{}".format(flavor))
        if response.status_code == requests.codes.ok:  # @UndefinedVariable
            print(json.dumps(response.json(), indent=2))
        else:
            print('Error!', response.text)

    def flavors_list(self, args):
        """
        List available node flavors

        Usage: deis flavors:list
        """
        response = self._dispatch('get', '/api/flavors')
        if response.status_code == requests.codes.ok:  # @UndefinedVariable
            data = response.json()
            if data['count'] == 0:
                print 'No flavors found'
                return
            print("=== {owner} Flavors".format(**data['results'][0]))
            for item in data['results']:
                print("{id}: params => {params}".format(**item))
        else:
            print('Error!', response.text)

    def formations(self, args):
        """
        Valid commands for formations:

        formations:create        create a new container formation
        formations:info          print a represenation of the formation
        formations:scale         scale container types (web=2, worker=1)
        formations:balance       rebalance the container formation
        formations:converge      force-converge all nodes in the formation
        formations:calculate     recalculate and update the formation databag
        formations:destroy       destroy a container formation

        Use `deis help [command]` to learn more
        """
        return self.formations_list(args)

    def formations_create(self, args):
        """
        Create a new formation

        If no ID is provided, one will be generated automatically.
        Providing a flavor automatically create a default runtime
        and proxy layer.

        Usage: deis formations:create [--id=<id> --flavor=<flavor>]
        """
        body = {}
        try:
            self._session.git_root()  # check for a git repository
        except EnvironmentError:
            print 'No git repository found, use `git init` to create one.'
            return
        for opt in ('--id',):
            o = args.get(opt)
            if o:
                body.update({opt.strip('-'): o})
        # if a flavor was passed, make sure its valid
        flavor = args.get('--flavor')
        if flavor:
            response = self._dispatch('get', '/api/flavors/{}'.format(flavor))
            if response.status_code != 200:
                print 'Flavor not found'
                return
        sys.stdout.write('Creating formation... ')
        sys.stdout.flush()
        response = self._dispatch('post', '/api/formations',
                                  json.dumps(body))
        if response.status_code == requests.codes.created:  # @UndefinedVariable
            data = response.json()
            formation = data['id']
            print("done, created {}".format(formation))
            # add a git remote
            hostname = urlparse.urlparse(self._settings['controller']).netloc
            git_remote = "git@{hostname}:{formation}.git".format(**locals())
            try:
                subprocess.check_call(
                    ['git', 'remote', 'add', '-f', 'deis', git_remote],
                    stdout=subprocess.PIPE)
            except subprocess.CalledProcessError:
                sys.exit(1)
            print('Git remote deis added')
            # create default layers if a flavor was provided
            if flavor:
                print
                self.layers_create({'<id>': 'runtime', '<flavor>': flavor})
                self.layers_create({'<id>': 'proxy', '<flavor>': flavor})
                print('\nUse `deis layers:scale proxy=1 runtime=1` to scale a basic formation')
        else:
            print('Error!', response.text)

    def formations_info(self, args):
        """
        Print info about a formation

        Usage: deis formations:info
        """
        formation = args.get('<formation>')
        if not formation:
            formation = self._session.formation
        response = self._dispatch('get', "/api/formations/{}".format(formation))
        if response.status_code == requests.codes.ok:  # @UndefinedVariable
            data = response.json()
            print("=== {} Formation".format(formation))
            print
            args = {'<formation>': data['id']}
            self.layers_list(args)
            print
            self.nodes_list(args)
            print
            self.containers_list(args)
        else:
            print('Error!', response.text)

    def formations_list(self, args):
        """
        List available formations

        Usage: deis formations:list
        """
        response = self._dispatch('get', '/api/formations')
        if response.status_code == requests.codes.ok:  # @UndefinedVariable
            data = response.json()
            if data['count'] == 0:
                print 'No formations found'
                return
            print("=== {owner} Formations".format(**data['results'][0]))
            for item in data['results']:
                formation = item['id']
                layers = json.loads(item.get('layers', {}))
                containers = json.loads(item.get('containers', {}))
                print("{formation}: layers => {layers} containers => {containers}".format(
                    **locals()))
        else:
            print('Error!', response.text)

    def formations_destroy(self, args):
        """
        Destroy a formation

        Usage: deis formations:destroy [<formation>] [--confirm=<confirm>]
        """
        formation = args.get('<formation>')
        if not formation:
            formation = self._session.formation
        confirm = args.get('--confirm')
        if confirm == formation:
            pass
        else:
            print """
 !    WARNING: Potentially Destructive Action
 !    This command will destroy: {formation}
 !    To proceed, type "{formation}" or re-run this command with --confirm={formation}
""".format(**locals())
            confirm = raw_input('> ').strip('\n')
            if confirm != formation:
                print('Destroy aborted')
                return
        sys.stdout.write("Destroying {}... ".format(formation))
        sys.stdout.flush()
        before = time.time()
        response = self._dispatch('delete', "/api/formations/{}".format(formation))
        if response.status_code in (requests.codes.no_content,  # @UndefinedVariable
                                    requests.codes.not_found):  # @UndefinedVariable
            print('done in {}s'.format(int(time.time() - before)))
            try:
                subprocess.check_call(
                    ['git', 'remote', 'rm', 'deis'],
                    stdout=subprocess.PIPE, stderr=subprocess.PIPE)
                print('Git remote deis removed')
            except subprocess.CalledProcessError:
                pass  # ignore error
        else:
            print('Error!', response.text)

    def formations_calculate(self, args, quiet=False):
        """
        Recalculate the formation's databag

        This command will recalculate the databag, update the Chef server
        and return the databag JSON.

        Usage: deis formations:calculate
        """
        formation = args.get('--formation')
        if not formation:
            formation = self._session.formation
        response = self._dispatch('post',
                                  "/api/formations/{}/calculate".format(formation))
        if response.status_code == requests.codes.ok:  # @UndefinedVariable
            databag = json.loads(response.content)
            if quiet is False:
                print(json.dumps(databag, indent=2))
            return databag
        else:
            print('Error!', response.text)

    def formations_converge(self, args):
        """
        Force converge a formation

        Converging a formation will force a Chef converge on
        all nodes in the formation, ensuring the formation is
        completely up-to-date.

        Usage: deis formations:converge
        """
        formation = args.get('--formation')
        if not formation:
            formation = self._session.formation
        sys.stdout.write('Converging {}... '.format(formation))
        sys.stdout.flush()
        before = time.time()
        response = self._dispatch('post',
                                  "/api/formations/{}/converge".format(formation))
        if response.status_code == requests.codes.ok:  # @UndefinedVariable
            print('done in {}s'.format(int(time.time() - before)))
            databag = json.loads(response.content)
            print(json.dumps(databag, indent=2))
        else:
            print('Error!', response.text)

    def keys(self, args):
        """
        Valid commands for SSH keys:

        keys:list        list SSH keys for the logged in user
        keys:add         add an SSH key
        keys:remove      remove an SSH key

        Use `deis help [command]` to learn more
        """
        return self.keys_list(args)

    def keys_add(self, args):
        """
        Add SSH keys for the logged in user

        Usage: deis keys:add [<key>]
        """
        path = args.get('<key>')
        if not path:
            ssh_dir = os.path.expanduser('~/.ssh')
            pubkeys = glob.glob(os.path.join(ssh_dir, '*.pub'))
            print('Found the following SSH public keys:')
            for i, k in enumerate(pubkeys):
                key = k.split(os.path.sep)[-1]
                print("{0}) {1}".format(i + 1, key))
            inp = raw_input('Which would you like to use with Deis? ')
            try:
                path = pubkeys[int(inp) - 1]
                key_id = path.split(os.path.sep)[-1].replace('.pub', '')
            except:
                print 'Aborting'
                return
        with open(path) as f:
            data = f.read()
        match = re.match(r'^(ssh-...) ([^ ]+) (.+)', data)
        if not match:
            print 'Could not parse public key material'
            return
        key_type, key_str, _key_comment = match.groups()
        body = {'id': key_id, 'public': "{0} {1}".format(key_type, key_str)}
        sys.stdout.write("Uploading {} to Deis... ".format(path))
        sys.stdout.flush()
        response = self._dispatch('post', '/api/keys', json.dumps(body))
        if response.status_code == requests.codes.created:  # @UndefinedVariable
            print('done')
        else:
            print('Error!', response.text)

    def keys_list(self, args):
        """
        List SSH keys for the logged in user

        Usage: deis keys:list
        """
        response = self._dispatch('get', '/api/keys')
        if response.status_code == requests.codes.ok:  # @UndefinedVariable
            data = response.json()
            if data['count'] == 0:
                print 'No keys found'
                return
            print("=== {owner} Keys".format(**data['results'][0]))
            for key in data['results']:
                public = key['public']
                print("{0} {1}...{2}".format(
                    key['id'], public[0:16], public[-10:]))
        else:
            print('Error!', response.text)

    def keys_remove(self, args):
        """
        Remove an SSH key for the logged in user

        Usage: deis keys:remove <key>
        """
        key = args.get('<key>')
        sys.stdout.write("Removing {} SSH Key... ".format(key))
        sys.stdout.flush()
        response = self._dispatch('delete', "/keys/{}".format(key))
        if response.status_code == requests.codes.no_content:  # @UndefinedVariable
            print('done')
        else:
            print('Error!', response.text)

    def layers(self, args):
        """
        Valid commands for node layers:

        layers:create        create a layer of nodes for a formation
        layers:scale         scale nodes in a layer (e.g. proxy=1 runtime=2)
        layers:list          list layers in a formation
        layers:destroy       destroy a layer of nodes in a formation

        Use `deis help [command]` to learn more
        """
        return self.layers_list(args)

    def layers_create(self, args):
        """
        Create a layer of nodes

        Usage: deis layers:create <id> <flavor> [options]

        Chef Options:

        --run_list=RUN_LIST         run-list to use when bootstrapping nodes
        --environment=ENVIRONMENT   chef environment to place nodes [default: _default]
        --attributes=INITIAL_ATTRS  initial attributes for nodes

        SSH Options:

        --ssh_username=USERNAME         username for ssh connections [default: ubuntu]
        --ssh_private_key=PRIVATE_KEY   private key for ssh comm (default: auto-gen)
        --ssh_public_key=PUBLIC_KEY     public key for ssh comm (default: auto-gen)

        """
        formation = args.get('--formation')
        if not formation:
            formation = self._session.formation
        body = {'id': args['<id>'], 'flavor': args['<flavor>']}
        for opt in ('--environment', '--initial_attributes', '--run_list',
                    '--ssh_username', '--ssh_private_key', '--ssh_public_key'):
            o = args.get(opt)
            if o:
                body.update({opt.strip('-'): o})
        # provide default run_list for runtime and proxy
        if not 'run_list' in body:
            if body['id'] == 'runtime':
                body['run_list'] = 'recipe[deis],recipe[deis::runtime]'
            elif body['id'] == 'proxy':
                body['run_list'] = 'recipe[deis],recipe[deis::proxy]'
        sys.stdout.write("Creating {} layer... ".format(args['<id>']))
        sys.stdout.flush()
        before = time.time()
        response = self._dispatch('post', "/api/formations/{}/layers".format(formation),
                                  json.dumps(body))
        if response.status_code == requests.codes.created:  # @UndefinedVariable
            print('done in {}s'.format(int(time.time() - before)))
        else:
            print('Error!', response.text)

    def layers_destroy(self, args):
        """
        Destroy a layer of nodes

        Usage: deis layers:destroy <id>
        """
        formation = args.get('--formation')
        if not formation:
            formation = self._session.formation
        layer = args['<id>']  # noqa
        sys.stdout.write("Destroying {layer} layer... ".format(**locals()))
        sys.stdout.flush()
        before = time.time()
        response = self._dispatch(
            'delete', "/api/formations/{formation}/layers/{layer}".format(**locals()))
        if response.status_code == requests.codes.no_content:  # @UndefinedVariable
            print('done in {}s'.format(int(time.time() - before)))
        else:
            print('Error!', response.text)

    def layers_list(self, args):
        """
        List layers for a formation

        Usage deis layers:list
        """
        formation = args.get('--formation')
        if not formation:
            formation = self._session.formation
        response = self._dispatch('get',
                                  "/api/formations/{}/layers".format(formation))
        if response.status_code == requests.codes.ok:  # @UndefinedVariable
            print("=== {} Layers".format(formation))
            data = response.json()
            format_str = "{id}: run_list => {run_list}"
            for item in data['results']:
                print(format_str.format(**item))
        else:
            print('Error!', response.text)

    def layers_scale(self, args):
        """
        Scale layers in a formation

        Scaling layers will launch or terminate nodes to meet the
        requested structure.

        Usage: deis layers:scale <type=num>...
        """
        formation = args.get('--formation')
        if not formation:
            formation = self._session.formation
        body = {}
        for type_num in args.get('<type=num>'):
            typ, count = type_num.split('=')
            body.update({typ: int(count)})
        print('Scaling layers... but first, coffee!')
        before = time.time()
        # TODO: add threaded spinner to print dots
        response = self._dispatch('post',
                                  "/api/formations/{}/scale/layers".format(formation),
                                  json.dumps(body))
        if response.status_code == requests.codes.ok:  # @UndefinedVariable
            print('done in {}s\n'.format(int(time.time() - before)))
            print('Use `git push deis master` to deploy to your formation')
        else:
            print('Error!', response.text)

    def logs(self, args):
        """
        Retrieve the most recent log events

        Usage: deis logs
        """
        formation = args.get('--formation')
        if not formation:
            formation = self._session.formation
        response = self._dispatch('post',
                                  "/api/formations/{}/logs".format(formation))
        if response.status_code == requests.codes.ok:  # @UndefinedVariable
            print(response.json())
        elif response.status_code == requests.codes.not_found:  # @UndefinedVariable
            print(response.json())
        else:
            print('Error!', response.text)

    def nodes(self, args):
        """
        Valid commands for nodes:

        nodes:list            list nodes for a formation
        nodes:info            print info for a given node
        nodes:destroy         destroy a node by ID

        Use `deis help [command]` to learn more
        """
        return self.nodes_list(args)

    def nodes_info(self, args):
        """
        Print info about a particular node

        Usage: deis nodes:info <node>
        """
        node = args.get('<node>')
        response = self._dispatch('get', "/api/nodes/{}".format(node))
        if response.status_code == requests.codes.ok:  # @UndefinedVariable
            print(json.dumps(response.json(), indent=2))
        else:
            print('Error!', response.text)

    def nodes_list(self, args):
        """
        List nodes for this formation

        Usage: deis nodes:list
        """
        formation = args.get('--formation')
        if not formation:
            formation = self._session.formation
        response = self._dispatch('get',
                                  "/api/formations/{}/nodes".format(formation))
        if response.status_code == requests.codes.ok:  # @UndefinedVariable
            print("=== {} Nodes".format(formation))
            data = response.json()
            format_str = "{id} {provider_id} {fqdn}"
            for item in data['results']:
                print(format_str.format(**item))
        else:
            print('Error!', response.text)

    def nodes_destroy(self, args):
        """
        Destroy a node by ID

        Nodes should normally be added/removed using a layers:scale
        command.  In the event you need to destroy a specific node,
        this command will terminate it at the cloud provider and
        purge it from the Chef server.

        Warning: Destroying a node will orphans any containers
        associated with it.  Use `formations:balance` to rebalance
        containers after destroying node(s) with this command.

        Usage: deis nodes:destroy <id>
        """
        formation = args.get('--formation')
        if not formation:
            formation = self._session.formation
        node = args['<id>']
        sys.stdout.write("Destroying {}... ".format(node))
        sys.stdout.flush()
        before = time.time()
        response = self._dispatch('delete',
                                  "/api/formations/{formation}/nodes/{node}".format(**locals()))
        if response.status_code == requests.codes.no_content:  # @UndefinedVariable
            print('done in {}s\n'.format(int(time.time() - before)))
        else:
            print('Error!', response.status_code, response.text)

    def providers(self, args):
        """
        Valid commands for providers:

        providers:list        list available providers for the logged in user
        providers:discover    discover provider credentials using envvars
        providers:create      create a new provider for use by deis
        providers:info        print information about a specific provider

        Use `deis help [command]` to learn more
        """
        return self.providers_list(args)

    def open(self, args):
        """
        Open a URL to the application in a browser

        Usage: deis open
        """
        formation = args.get('--formation')
        if not formation:
            formation = self._session.formation
        # TODO: replace with a proxy lookup that doesn't have any side effects
        # this currently recalculates and updates the databag
        response = self._dispatch('post',
                                  "/api/formations/{}/calculate".format(formation))
        if response.status_code == requests.codes.ok:  # @UndefinedVariable
            databag = json.loads(response.content)
            proxy = random.choice(databag['nodes'].get('proxy', {}).values())
            # use the OS's default handler to open this URL
            webbrowser.open('http://{}/'.format(proxy))
            return proxy
        else:
            print('Error!', response.text)

    def providers_create(self, args):
        """
        Create a provider for use by Deis

        This command is only necessary when adding a duplicate
        set of credentials for a provider like EC2.  User accounts
        already come with a default EC2 provider that has empty
        credentials, which should be updated in place.

        Use `providers:discover` to update credentials of the
        default providers and flavors that come pre-installed.

        Usage: deis providers:create --type=<type> [--id=<id> --creds=<creds>]
        """
        type = args.get('--type')  # @ReservedAssignment
        if type == 'ec2':
            # read creds from envvars
            for k in ('AWS_ACCESS_KEY', 'AWS_SECRET_KEY'):
                if not k in os.environ:
                    msg = "Missing environment variable: {}".format(k)
                    raise EnvironmentError(msg)
            creds = {'access_key': os.environ['AWS_ACCESS_KEY'],
                     'secret_key': os.environ['AWS_SECRET_KEY']}
        id = args.get('--id')  # @ReservedAssignment
        if not id:
            id = type  # @ReservedAssignment
        body = {'id': id, 'type': type, 'creds': json.dumps(creds)}
        response = self._dispatch('post', '/api/providers',
                                  json.dumps(body))
        if response.status_code == requests.codes.created:  # @UndefinedVariable
            print("{0[id]}".format(response.json()))
        else:
            print('Error!', response.text)

    def providers_discover(self, args):
        """
        Discover and update provider credentials

        This command will discover provider credentials using
        standard environment variables like AWS_ACCESS_KEY and
        AWS_SECRET_KEY.  It will use those credentials to update
        the existing provider record, allowing you to use
        pre-installed node flavors.

        Usage: deis providers:discover
        """
        # look for ec2 credentials
        if 'AWS_ACCESS_KEY' in os.environ and 'AWS_SECRET_KEY' in os.environ:
            print("Found EC2 credentials: {}".format(os.environ['AWS_ACCESS_KEY']))
            inp = raw_input('Import these credentials? (y/n) : ')
            if inp.lower().strip('\n') != 'y':
                print 'Aborting.'
                return
            creds = {'access_key': os.environ['AWS_ACCESS_KEY'],
                     'secret_key': os.environ['AWS_SECRET_KEY']}
            body = {'creds': json.dumps(creds)}
            sys.stdout.write('Uploading EC2 credentials... ')
            sys.stdout.flush()
            response = self._dispatch('patch', '/api/providers/ec2',
                                      json.dumps(body))
            if response.status_code == requests.codes.ok:  # @UndefinedVariable
                print 'done'
            else:
                print('Error!', response.text)
        else:
            print 'No credentials discovered, did you install the EC2 Command Line tools?'
            return

    def providers_info(self, args):
        """
        Print information about a specific provider

        Usage: deis providers:info <provider>
        """
        provider = args.get('<provider>')
        response = self._dispatch('get', "/api/providers/{}".format(provider))
        if response.status_code == requests.codes.ok:  # @UndefinedVariable
            print(json.dumps(response.json(), indent=2))
        else:
            print('Error!', response.text)

    def providers_list(self, args):
        """
        List providers for the logged in user

        Usage: deis providers:list
        """
        response = self._dispatch('get', '/api/providers')
        if response.status_code == requests.codes.ok:  # @UndefinedVariable
            data = response.json()
            if data['count'] == 0:
                print 'No providers found'
                return
            print("=== {owner} Providers".format(**data['results'][0]))
            for item in data['results']:
                creds = json.loads(item['creds'])
                creds.pop('secret_key')
                print("{} => {}".format(item['id'], creds))
        else:
            print('Error!', response.text)

    def releases(self, args):
        """
        Valid commands for releases:

        releases:list        list a formation's release history
        releases:info        print information about a specific release
        releases:rollback    coming soon!

        Use `deis help [command]` to learn more
        """
        return self.releases_list(args)

    def releases_info(self, args):
        """
        Print info about a particular release

        Usage: deis releases:info <version>
        """
        version = args.get('<version>')
        formation = args.get('--formation')
        if not formation:
            formation = self._session.formation
        response = self._dispatch(
            'get', "/api/formations/{formation}/releases/{version}".format(**locals()))
        if response.status_code == requests.codes.ok:  # @UndefinedVariable
            print(json.dumps(response.json(), indent=2))
        else:
            print('Error!', response.text)

    def releases_list(self, args):
        """
        List release history for a formation

        Usage: deis releases:list
        """
        formation = args.get('--formation')
        if not formation:
            formation = self._session.formation
        response = self._dispatch('get', '/api/formations/{formation}/releases'.format(**locals()))
        if response.status_code == requests.codes.ok:  # @UndefinedVariable
            print('=== {0} Releases'.format(formation))
            data = response.json()
            for item in data['results']:
                print('{version} {created}'.format(**item))
        else:
            print('Error!', response.text)


def parse_args(cmd):
    """
    Parse command-line args applying shortcuts and looking for help flags
    """
    shortcuts = {
        'register': 'auth:register',
        'login': 'auth:login',
        'logout': 'auth:logout',
        'create': 'formations:create',
        'info': 'formations:info',
        'balance': 'formations:balance',
        'calculate': 'formations:calculate',
        'converge': 'formations:converge',
        'destroy': 'formations:destroy',
        'scale': 'containers:scale',
        'ps': 'containers:list',
    }
    if cmd == 'help':
        cmd = sys.argv[-1]
        help_flag = True
    else:
        cmd = sys.argv[1]
        help_flag = False
    # swap cmd with shortcut
    if cmd in shortcuts:
        cmd = shortcuts[cmd]
        # change the cmdline arg itself for docopt
        if not help_flag:
            sys.argv[1] = cmd
        else:
            sys.argv[2] = cmd
    # convert : to _ for matching method names and docstrings
    if ':' in cmd:
        cmd = '_'.join(cmd.split(':'))
    return cmd, help_flag


def main():
    """
    Create a client, parse the arguments received on the command line, and
    call the appropriate method on the client.
    """
    cli = DeisClient()
    args = docopt(__doc__, version='Deis CLI {}'.format(__version__),
                  options_first=True)
    cmd = args['<command>']
    cmd, help_flag = parse_args(cmd)
    # print help if it was asked for
    if help_flag:
        if cmd != 'help':
            if cmd in dir(cli):
                print trim(getattr(cli, cmd).__doc__)
                return
        docopt(__doc__, argv=['--help'])
    # re-parse docopt with the relevant docstring
    if cmd in dir(cli):
        docstring = trim(getattr(cli, cmd).__doc__)
        if 'Usage: ' in docstring:
            args.update(docopt(docstring))
    # find the method for dispatching
    if hasattr(cli, cmd):
        method = getattr(cli, cmd)
    else:
        raise DocoptExit('Found no matching command')
    # dispatch the CLI command
    try:
        method(args)
    except EnvironmentError as err:
        raise DocoptExit(err.message)


if __name__ == '__main__':
    main()
    sys.exit(0)