Fix #34, initialized compute engine support.

gcloud/compute/__init__.py

@@ -0,0 +1,14 @@
+__version__ = '0.1'
+
+# TODO: Allow specific scopes and authorization levels.
+SCOPE = ('https://www.googleapis.com/auth/compute')
+"""The scope required for authenticating as a Compute Engine consumer."""
+
+
+def get_connection(project_name, client_email, private_key_path):
+  from gcloud.credentials import Credentials
+  from gcloud.compute.connection import Connection
+
+  credentials = Credentials.get_for_service_account(
+      client_email, private_key_path, scope=SCOPE)
+  return Connection(project_name=project_name, credentials=credentials)

gcloud/compute/connection.py

@@ -0,0 +1,115 @@
+import json
+import urllib
+
+from gcloud import connection
+from gcloud.compute import exceptions
+from gcloud.compute.instance import Instance
+
+
+class Connection(connection.Connection):
+  """A connection to the Google Compute Engine via the Protobuf API.
+
+  This class should understand only the basic types (and protobufs)
+  in method arguments, however should be capable of returning advanced types.
+
+  :type credentials: :class:`gcloud.credentials.Credentials`
+  :param credentials: The OAuth2 Credentials to use for this connection.
+  """
+
+  API_BASE_URL = 'https://www.googleapis.com'
+  """The base of the API call URL."""
+
+  API_VERSION = 'v1'
+  """The version of the API, used in building the API call's URL."""
+
+  API_URL_TEMPLATE = ('{api_base_url}/compute/{api_version}/{path}')
+  """A template used to craft the URL pointing toward a particular API call."""
+
+  _EMPTY = object()
+  """A pointer to represent an empty value for default arguments."""
+
+  def __init__(self, project_name=None, *args, **kwargs):
+
+    super(Connection, self).__init__(*args, **kwargs)
+
+    self.project_name = project_name
+
+  def build_api_url(self, path, query_params=None, api_base_url=None,
+                    api_version=None):
+
+    url = self.API_URL_TEMPLATE.format(
+        api_base_url=(api_base_url or self.API_BASE_URL),
+        api_version=(api_version or self.API_VERSION),
+        path=path)
+
+    query_params = query_params or {}
+    query_params.update({'project': self.project_name})
+    url += '?' + urllib.urlencode(query_params)
+
+    return url
+
+  def make_request(self, method, url, data=None, content_type=None,
+                   headers=None):
+
+    headers = headers or {}
+    headers['Accept-Encoding'] = 'gzip'
+
+    if data:
+      content_length = len(str(data))
+    else:
+      content_length = 0
+
+    headers['Content-Length'] = content_length
+
+    if content_type:
+      headers['Content-Type'] = content_type
+
+    return self.http.request(uri=url, method=method, headers=headers,
+                             body=data)
+
+  def api_request(self, method, path=None, query_params=None,
+                  data=None, content_type=None,
+                  api_base_url=None, api_version=None,
+                  expect_json=True):
+
+    url = self.build_api_url(path=path, query_params=query_params,
+                             api_base_url=api_base_url,
+                             api_version=api_version)
+
+    # Making the executive decision that any dictionary
+    # data will be sent properly as JSON.
+    if data and isinstance(data, dict):
+      data = json.dumps(data)
+      content_type = 'application/json'
+
+    response, content = self.make_request(
+        method=method, url=url, data=data, content_type=content_type)
+
+    # TODO: Add better error handling.
+    if response.status == 404:
+      raise exceptions.NotFoundError(response, content)
+    elif not 200 <= response.status < 300:
+      raise exceptions.ConnectionError(response, content)
+
+    if content and expect_json:
+      # TODO: Better checking on this header for JSON.
+      content_type = response.get('content-type', '')
+      if not content_type.startswith('application/json'):
+        raise TypeError('Expected JSON, got %s' % content_type)
+      return json.loads(content)
+
+    return content
+
+  def get_instance(self, instance_name, zone):
+    instance = self.new_instance(instance_name, zone)
+    response = self.api_request(method='GET', path=instance.path)
+    return Instance.from_dict(response, connection=self)
+
+  def reset_instance(self, instance):
+    self.api_request(method='POST', path=instance.path + 'reset')
+    return True
+
+  # TODO: Add instance and error handling.
+  def new_instance(self, instance, zone):
+    if isinstance(instance, basestring):
+      return Instance(connection=self, name=instance, zone=zone)

gcloud/compute/demo/__init__.py

@@ -0,0 +1,15 @@
+import os
+from gcloud import compute
+
+
+__all__ = ['get_connection', 'CLIENT_EMAIL', 'PRIVATE_KEY_PATH',
+           'PROJECT_NAME']
+
+
+CLIENT_EMAIL = '524635209885-rda26ks46309o10e0nc8rb7d33rn0hlm@developer.gserviceaccount.com'
+PRIVATE_KEY_PATH = os.path.join(os.path.dirname(__file__), 'demo.key')
+PROJECT_NAME = 'gceremote'
+
+
+def get_connection():
+  return compute.get_connection(PROJECT_NAME, CLIENT_EMAIL, PRIVATE_KEY_PATH)

gcloud/compute/demo/demo.py

@@ -0,0 +1,17 @@
+# Welcome to the gCloud Compute Demo! (hit enter)
+
+# We're going to walk through some of the basics...,
+# Don't worry though. You don't need to do anything, just keep hitting enter...
+
+# Let's start by importing the demo module and getting a connection:
+from gcloud.compute import demo
+connection = demo.get_connection()
+
+# OK, now let's retrieve an instance
+instance = connection.get_instance('gcloud-computeengine-instance',
+                                   'us-central1-b')
+
+# Let us give that instance a reset - Got the reset!
+instance.reset()
+
+# Thats it for now more is coming soon

gcloud/compute/exceptions.py

@@ -0,0 +1,18 @@
+# TODO: Make these super useful.
+
+
+class ComputeError(Exception):
+  pass
+
+
+class ConnectionError(ComputeError):
+
+  def __init__(self, response, content):
+    message = str(response) + content
+    super(ConnectionError, self).__init__(message)
+
+
+class NotFoundError(ConnectionError):
+
+  def __init__(self, response, content):
+    self.message = 'GET %s returned a 404.' % (response.url)

gcloud/compute/instance.py

@@ -0,0 +1,33 @@
+class Instance(object):
+
+  def __init__(self, connection=None, name=None, zone=None):
+    self.connection = connection
+    self.name = name
+    self.zone = zone
+
+  @classmethod
+  def from_dict(cls, instance_dict, connection=None):
+    """Construct a new bucket from a dictionary of data from Cloud Storage.
+
+    :type bucket_dict: dict
+    :param bucket_dict: The dictionary of data to construct a bucket from.
+
+    :rtype: :class:`Bucket`
+    :returns: A bucket constructed from the data provided.
+    """
+
+    return cls(connection=connection, name=instance_dict['name'],
+               zone=instance_dict['zone'].split('/').pop())
+
+  @property
+  def path(self):
+    """The URL path to this instances."""
+
+    if not self.name:
+      raise ValueError('Cannot determine path without instance zone and name.')
+
+    return ('projects/%s/zones/%s/instances/%s/' %
+            (self.connection.project_name, self.zone, self.name))
+
+  def reset(self):
+    return self.connection.reset_instance(self)