Establish the supported importable interface

* Consumers of this client should not depend on being able to import
  any module other than glanceclient and glanceclient
* The only attributs of the glanceclient module are Client
  and __version__
* The attributes of the glanceclient.exc modules have yet to be
  locked down
* glanceclient.common.exceptions was replaced with a placeholder
  module until consumers of it are updated

Change-Id: Iea9648cd06906d65764987c1f2ee5a88ebeee748

1 files changed, 131 insertions, 0 deletions

diff --git a/glanceclient/exc.py b/glanceclient/exc.py
new file mode 100644
index 0000000..d88f94b
--- /dev/null
+++ b/glanceclient/exc.py
@@ -0,0 +1,131 @@
+"""
+Exception definitions.
+"""
+
+
+class CommandError(Exception):
+    pass
+
+
+class NoTokenLookupException(Exception):
+    """This form of authentication does not support looking up
+       endpoints from an existing token."""
+    pass
+
+
+class EndpointNotFound(Exception):
+    """Could not find Service or Region in Service Catalog."""
+    pass
+
+
+class SchemaNotFound(KeyError):
+    """Could not find schema"""
+    pass
+
+
+class ClientException(Exception):
+    """
+    The base exception class for all exceptions this library raises.
+    """
+    def __init__(self, code, message=None, details=None):
+        self.code = code
+        self.message = message or self.__class__.message
+        self.details = details
+
+    def __str__(self):
+        return "%s (HTTP %s)" % (self.message, self.code)
+
+
+class BadRequest(ClientException):
+    """
+    HTTP 400 - Bad request: you sent some malformed data.
+    """
+    http_status = 400
+    message = "Bad request"
+
+
+class Unauthorized(ClientException):
+    """
+    HTTP 401 - Unauthorized: bad credentials.
+    """
+    http_status = 401
+    message = "Unauthorized"
+
+
+class Forbidden(ClientException):
+    """
+    HTTP 403 - Forbidden: your credentials don't give you access to this
+    resource.
+    """
+    http_status = 403
+    message = "Forbidden"
+
+
+class NotFound(ClientException):
+    """
+    HTTP 404 - Not found
+    """
+    http_status = 404
+    message = "Not found"
+
+
+class Conflict(ClientException):
+    """
+    HTTP 409 - Conflict
+    """
+    http_status = 409
+    message = "Conflict"
+
+
+class OverLimit(ClientException):
+    """
+    HTTP 413 - Over limit: you're over the API limits for this time period.
+    """
+    http_status = 413
+    message = "Over limit"
+
+
+# NotImplemented is a python keyword.
+class HTTPNotImplemented(ClientException):
+    """
+    HTTP 501 - Not Implemented: the server does not support this operation.
+    """
+    http_status = 501
+    message = "Not Implemented"
+
+
+# In Python 2.4 Exception is old-style and thus doesn't have a __subclasses__()
+# so we can do this:
+#     _code_map = dict((c.http_status, c)
+#                      for c in ClientException.__subclasses__())
+#
+# Instead, we have to hardcode it:
+_code_map = dict((c.http_status, c) for c in [BadRequest, Unauthorized,
+                   Forbidden, NotFound, OverLimit, HTTPNotImplemented])
+
+
+def from_response(response, body):
+    """
+    Return an instance of an ClientException or subclass
+    based on an httplib2 response.
+
+    Usage::
+
+        resp, body = http.request(...)
+        if resp.status != 200:
+            raise exception_from_response(resp, body)
+    """
+    cls = _code_map.get(response.status, ClientException)
+    if body:
+        if hasattr(body, 'keys'):
+            error = body[body.keys()[0]]
+            message = error.get('message', None)
+            details = error.get('details', None)
+        else:
+            # If we didn't get back a properly formed error message we
+            # probably couldn't communicate with Keystone at all.
+            message = "Unable to communicate with image service: %s." % body
+            details = None
+        return cls(code=response.status, message=message, details=details)
+    else:
+        return cls(code=response.status)