Treat URI_PORT as a known option in proxy server

[pacheco017]

Current implementation of proxy server replies with

4.02 Bad Option
Unsafe options in request: URI_PORT

when a client makes a request through it specifying the port it wants to use.

Is there any rationale behind treating URI_PORT as a not-known option in proxy.server.raise_unless_safe?

Adding URI_PORT to the set of known options lets the request reach the desired server and the final response arrive to the client.

Example:

# Server listening on 172.17.0.26:5683
./server.py

# Reverse Proxy listening on 172.17.0.46:6666, forwards requests to the server above
./coap-proxy --reverse --server-address 172.17.0.46 --server-port 6666 --pathbased "xyz":"172.17.0.26"

# Client on 172.17.0.27, requests to the proxy server
./coap-client -v coap://172.17.0.46:6666/xyz/time
4.02 Bad Option
Unsafe options in request: URI_PORT

Adding URI_PORT to the set of known options in proxy.server.raise_unless_safe lets the client get the expected reply from the server:

# Same setup as above
./coap-client.py -v coap://172.17.0.46:6666/xyz/time
2015-07-24 12:39
(No newline at end of message)

[chrysn]

it's just an oversight