X-Git-Url: https://git.notmuchmail.org/git?a=blobdiff_plain;f=bindings%2Fpython%2Fnotmuch%2Fglobals.py;h=a42f2a40d68f4217d9f29691d44eb9b8ac8ef97b;hb=05926adf73e7b1bad0faa4a0a5514d554353cdaa;hp=097ab96800d1dcaa3336f037605be61561b1d0fd;hpb=c16e47fe23901951399c9c463e82292a36462b73;p=notmuch

diff --git a/bindings/python/notmuch/globals.py b/bindings/python/notmuch/globals.py
index 097ab968..a42f2a40 100644
--- a/bindings/python/notmuch/globals.py
+++ b/bindings/python/notmuch/globals.py
@@ -23,7 +23,7 @@ from ctypes.util import find_library
 #-----------------------------------------------------------------------------
 #package-global instance of the notmuch library
 try:
-    nmlib = CDLL("libnotmuch.so.1")
+    nmlib = CDLL("libnotmuch.so.2")
 except:
     raise ImportError("Could not find shared 'notmuch' library.")
 
@@ -89,10 +89,46 @@ Invoke the class method `notmuch.STATUS.status2str` with a status value as
 argument to receive a human readable string"""
 STATUS.__name__ = 'STATUS'
 
-
 class NotmuchError(Exception):
+    """Is initiated with a (notmuch.STATUS[, message=None]). It will not
+    return an instance of the class NotmuchError, but a derived instance
+    of a more specific Error Message, e.g. OutOfMemoryError. Each status
+    but SUCCESS has a corresponding subclassed Exception."""
+
+    @classmethod
+    def get_exc_subclass(cls, status):
+        """Returns a fine grained Exception() type,detailing the error status"""
+        subclasses = {
+            STATUS.OUT_OF_MEMORY: OutOfMemoryError,
+            STATUS.READ_ONLY_DATABASE: ReadOnlyDatabaseError,
+            STATUS.XAPIAN_EXCEPTION: XapianError,
+            STATUS.FILE_ERROR: FileError,
+            STATUS.FILE_NOT_EMAIL: FileNotEmailError,
+            STATUS.DUPLICATE_MESSAGE_ID: DuplicateMessageIdError,
+            STATUS.NULL_POINTER: NullPointerError,
+            STATUS.TAG_TOO_LONG: TagTooLongError,
+            STATUS.UNBALANCED_FREEZE_THAW: UnbalancedFreezeThawError,
+            STATUS.UNBALANCED_ATOMIC: UnbalancedAtomicError,
+            STATUS.NOT_INITIALIZED: NotInitializedError
+        }
+        assert 0 < status <= len(subclasses)
+        return subclasses[status]
+
+    def __new__(cls, *args, **kwargs):
+        """Return a correct subclass of NotmuchError if needed
+
+        We return a NotmuchError instance if status is None (or 0) and a
+        subclass that inherits from NotmuchError depending on the
+        'status' parameter otherwise."""
+        # get 'status'. Passed in as arg or kwarg?
+        status = args[0] if len(args) else kwargs.get('status', None)
+        # no 'status' or cls is subclass already, return 'cls' instance
+        if not status or cls != NotmuchError:
+            return super(NotmuchError, cls).__new__(cls)
+        subclass = cls.get_exc_subclass(status) # which class to use?
+        return subclass.__new__(subclass, *args, **kwargs)
+
     def __init__(self, status=None, message=None):
-        """Is initiated with a (notmuch.STATUS[,message=None])"""
         self.status = status
         self.message = message
 
@@ -104,6 +140,36 @@ class NotmuchError(Exception):
         else:
             return 'Unknown error'
 
+# List of Subclassed exceptions that correspond to STATUS values and are
+# subclasses of NotmuchError.
+class OutOfMemoryError(NotmuchError):
+    pass
+class ReadOnlyDatabaseError(NotmuchError):
+    pass
+class XapianError(NotmuchError):
+    pass
+class FileError(NotmuchError):
+    pass
+class FileNotEmailError(NotmuchError):
+    pass
+class DuplicateMessageIdError(NotmuchError):
+    pass
+class NullPointerError(NotmuchError):
+    pass
+class TagTooLongError(NotmuchError):
+    pass
+class UnbalancedFreezeThawError(NotmuchError):
+    pass
+class UnbalancedAtomicError(NotmuchError):
+    pass
+class NotInitializedError(NotmuchError):
+    """Derived from NotmuchError, this occurs if the underlying data
+    structure (e.g. database is not initialized (yet) or an iterator has
+    been exhausted. You can test for NotmuchError with .status =
+    STATUS.NOT_INITIALIZED"""
+    pass
+
+
 def _str(value):
     """Ensure a nicely utf-8 encoded string to pass to libnotmuch