'''

Facebook error classes also see

http://fbdevwiki.com/wiki/Error_codes#User_Permission_Errors

'''

import ssl

try:

import urllib2

except ImportError:

import urllib.error as urllib2

class OpenFacebookException(Exception):

'''

BaseClass for all open facebook errors

'''

@classmethod

def codes_list(cls):

'''

Returns the codes as a list of instructions

'''

if hasattr(cls, 'codes'):

codes_list = [cls.codes]

if isinstance(cls.codes, list):

codes_list = cls.codes

return codes_list

@classmethod

def range(cls):

'''

Returns for how many codes this Exception, matches with the eventual

goal of matching an error to the most specific error class

'''

range = 0

codes_list = cls.codes_list()

for c in codes_list:

if isinstance(c, tuple):

start, stop = c

range += stop - start + 1

else:

range += 1

# make sure none specific exceptions are last in the order

if not range:

range = 1000

return range

class ParameterException(OpenFacebookException):

'''

100-189

190 and up are oauth errors

'''

codes = (100, 189)

class UnknownException(OpenFacebookException):

'''

Raised when facebook themselves don't know what went wrong

'''

codes = 1

class OAuthException(OpenFacebookException):

pass

class PermissionException(OAuthException):

'''

200-300

'''

codes = [3, (200, 299)]

class UserPermissionException(PermissionException):

codes = (300, 399)

class FeedActionLimit(UserPermissionException):

'''

When you posted too many times from one user acount

'''

codes = 341

class OpenGraphException(OpenFacebookException):

'''

Raised when we get error 3502, representing a problem with facebook

open graph data on the page

'''

codes = 3502

class DuplicateStatusMessage(OpenFacebookException):

codes = 506

class MissingParameter(OpenFacebookException):

pass

class AliasException(OpenFacebookException):

'''

When you send a request to a non existant url facebook gives this error

instead of a 404....

'''

codes = 803

class UnsupportedDeleteRequest(OpenFacebookException):

pass

class ParseException(OpenFacebookException):

'''

Anything preventing us from parsing the Facebook response

'''

pass

class FacebookUnreachable(OpenFacebookException):

'''

Timeouts, 500s, SSL errors etc

'''

pass

class FacebookSSLError(FacebookUnreachable, ssl.SSLError):

pass

class FacebookHTTPError(FacebookUnreachable, urllib2.HTTPError):

pass

class FacebookURLError(FacebookUnreachable, urllib2.URLError):

pass

def map_unreachable_exception(e):

'''

We always raise the original and new subclass to

- preserve backwards compatibility

'''

exception_class = FacebookUnreachable

if isinstance(e, ssl.SSLError):

exception_class = FacebookSSLError

elif isinstance(e, urllib2.HTTPError):

exception_class = FacebookHTTPError

elif isinstance(e, urllib2.URLError):

exception_class = FacebookURLError

return exception_class

def convert_unreachable_exception(e, error_format='Facebook is unreachable %s'):

'''

Converts an SSLError, HTTPError or URLError into something subclassing

FacebookUnreachable allowing code to easily try except this

'''

exception_class = map_unreachable_exception(e)

error_message = error_format % str(e)

exception = exception_class(error_message)

return exception

def get_exception_classes():

from open_facebook import exceptions as facebook_exceptions

all_exceptions = dir(facebook_exceptions)

classes = [getattr(facebook_exceptions, e, None) for e in all_exceptions]

exception_classes = [e for e in classes if getattr(

e, 'codes', None) and issubclass(

e, OpenFacebookException)]

return exception_classes