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diff --git a/Demo/pdist/README b/Demo/pdist/README deleted file mode 100644 index b3fac24..0000000 --- a/Demo/pdist/README +++ /dev/null @@ -1,121 +0,0 @@ -Filesystem, RCS and CVS client and server classes -================================================= - -*** See the security warning at the end of this file! *** - -This directory contains various modules and classes that support -remote file system operations. - -CVS stuff ---------- - -rcvs Script to put in your bin directory -rcvs.py Remote CVS client command line interface - -cvslib.py CVS admin files classes (used by rrcs) -cvslock.py CVS locking algorithms - -RCS stuff ---------- - -rrcs Script to put in your bin directory -rrcs.py Remote RCS client command line interface - -rcsclient.py Return an RCSProxyClient instance - (has reasonable default server/port/directory) - -RCSProxy.py RCS proxy and server classes (on top of rcslib.py) - -rcslib.py Local-only RCS base class (affects stdout & - local work files) - -FSProxy stuff -------------- - -sumtree.py Old demo for FSProxy -cmptree.py First FSProxy client (used to sync from the Mac) -FSProxy.py Filesystem interface classes - -Generic client/server stuff ---------------------------- - -client.py Client class -server.py Server class - -security.py Security mix-in class (not very secure I think) - -Other generic stuff -------------------- - -cmdfw.py CommandFrameWork class - (used by rcvs, should be used by rrcs as well) - - -Client/Server operation ------------------------ - -The Client and Server classes implement a simple-minded RPC protocol, -using Python's pickle module to transfer arguments, return values and -exceptions with the most generality. The Server class is instantiated -with a port number on which it should listen for requests; the Client -class is instantiated with a host name and a port number where it -should connect to. Once a client is connected, a TCP connection is -maintained between client and server. - -The Server class currently handles only one connection at a time; -however it could be rewritten to allow various modes of operations, -using multiple threads or processes or the select() system call as -desired to serve multiple clients simultaneously (when using select(), -still handling one request at a time). This would not require -rewriting of the Client class. It may also be possible to adapt the -code to use UDP instead of TCP, but then both classes will have to be -rewritten (and unless extensive acknowlegements and request serial -numbers are used, the server should handle duplicate requests, so its -semantics should be idempotent -- shrudder). - -Even though the FSProxy and RCSProxy modules define client classes, -the client class is fully generic -- what methods it supports is -determined entirely by the server. The server class, however, must be -derived from. This is generally done as follows: - - from server import Server - from client import Client - - # Define a class that performs the operations locally - class MyClassLocal: - def __init__(self): ... - def _close(self): ... - - # Derive a server class using multiple inheritance - class MyClassServer(MyClassLocal, Server): - def __init__(self, address): - # Must initialize MyClassLocal as well as Server - MyClassLocal.__init__(self) - Server.__init__(self, address) - def _close(self): - Server._close() - MyClassLocal._close() - - # A dummy client class - class MyClassClient(Client): pass - -Note that because MyClassLocal isn't used in the definition of -MyClassClient, it would actually be better to place it in a separate -module so the definition of MyClassLocal isn't executed when we only -instantiate a client. - -The modules client and server should probably be renamed to Client and -Server in order to match the class names. - - -*** Security warning: this version requires that you have a file -$HOME/.python_keyfile at the server and client side containing two -comma- separated numbers. The security system at the moment makes no -guarantees of actuallng being secure -- however it requires that the -key file exists and contains the same numbers at both ends for this to -work. (You can specify an alternative keyfile in $PYTHON_KEYFILE). -Have a look at the Security class in security.py for details; -basically, if the key file contains (x, y), then the security server -class chooses a random number z (the challenge) in the range -10..100000 and the client must be able to produce pow(z, x, y) -(i.e. z**x mod y). |