Improved error reporting when rdiff-backup doesn't start correctly on

the remote side.


git-svn-id: http://svn.savannah.nongnu.org/svn/rdiff-backup@27 2b77aa54-bcbc-44c9-a7ec-4f6cf2b41109

trunk/rdiff-backup/rdiff_backup/connection.py

@@ -7,6 +7,7 @@ import types, os, tempfile, cPickle, shutil, traceback
 #
 
 class ConnectionError(Exception): pass
+class ConnectionReadError(ConnectionError): pass
 
 class ConnectionQuit(Exception): pass
 
@@ -210,8 +211,9 @@ class LowLevelPipeConnection(Connection):
 	def _get(self):
 		"""Read an object from the pipe and return (req_num, value)"""
 		header_string = self.inpipe.read(9)
-		assert len(header_string) == 9, \
-			   "Error reading from pipe (problem probably originated remotely)"
+		if not len(header_string) == 9:
+			raise ConnectionReadError("Truncated header string (problem "
+									  "probably originated remotely)")
 		try:
 			format_string, req_num, length = (header_string[0],
 											  ord(header_string[1]),

trunk/rdiff-backup/src/connection.py

@@ -7,6 +7,7 @@ import types, os, tempfile, cPickle, shutil, traceback
 #
 
 class ConnectionError(Exception): pass
+class ConnectionReadError(ConnectionError): pass
 
 class ConnectionQuit(Exception): pass
 
@@ -210,8 +211,9 @@ class LowLevelPipeConnection(Connection):
 	def _get(self):
 		"""Read an object from the pipe and return (req_num, value)"""
 		header_string = self.inpipe.read(9)
-		assert len(header_string) == 9, \
-			   "Error reading from pipe (problem probably originated remotely)"
+		if not len(header_string) == 9:
+			raise ConnectionReadError("Truncated header string (problem "
+									  "probably originated remotely)")
 		try:
 			format_string, req_num, length = (header_string[0],
 											  ord(header_string[1]),

trunk/rdiff-backup/src/setconnections.py

@@ -109,15 +109,26 @@ class SetConnections:
 		conn_number = len(Globals.connections)
 		conn = PipeConnection(stdout, stdin, conn_number)
 
-		cls.check_connection_version(conn)
+		cls.check_connection_version(conn, remote_cmd)
 		Log("Registering connection %d" % conn_number, 7)
 		cls.init_connection_routing(conn, conn_number, remote_cmd)
 		cls.init_connection_settings(conn)
 		return conn
 
-	def check_connection_version(cls, conn):
+	def check_connection_version(cls, conn, remote_cmd):
 		"""Log warning if connection has different version"""
-		remote_version = conn.Globals.get('version')
+		try: remote_version = conn.Globals.get('version')
+		except ConnectionReadError, exception:
+			Log.FatalError("""%s
+
+Couldn't start up the remote connection by executing
+
+    %s
+
+Remember that, under the default settings, rdiff-backup must be
+installed in the PATH on the remote system.  See the man page for more
+information.""" % (exception, remote_cmd))
+		
 		if remote_version != Globals.version:
 			Log("Warning: Local version %s does not match remote version %s."
 				% (Globals.version, remote_version), 2)