support bi-directional RPC between two services
An RpcPeer (actually, an instance of a derived class) tries to open a
connection to another RpcPeer. If the other RpcPeer is not yet
running, the RpcPeer will create its own port and wait for the other
RpcPeer to open a connection. When either RpcPeer opens a connection,
each RpcPeer will create both a reader and a writer so each RpcPeer
can send RPC requests to its opposite over the same connection.
- RpcPeer(const char* lPath, int lPort = 0)
Store the arguments for later use since a base constructor can't call
a derived class's virtual function. The derived class's constructor
should call ``init'', described below.
- void init(const char* rPath)
Find the host name and port number registered by the other RpcPeer and
try to open a connection to it. If it's not running, create our own
port and wait for the other RpcPeer to open a connection.
- void run()
- void quitRunning()
Read RPC requests continuously until ``quitRunning()'' terminates the
loop. If you're using InterViews, you don't have to call ``run()''
since the InterViews event-reading code will also read RPC requests.
- virtual boolean createReaderAndWriter(const char* rHost, int rPort) = 0
- virtual void createReaderAndWriter(int fd) = 0
You must define both functions in a derived class in order to start
reading and writing RPC requests over the connection. Typically both
functions would create a writer using the given parameters and then
attach a reader to the writer's rpcstream.