Network Proxy to dump the application level forward traffic in plain text in the console and in a file.

mkfifo fifo; while true ; do echo "Waiting for new event"; nc -l 8080 < fifo | tee -a proxy.txt /dev/stderr | nc 192.168.0.1 80 > fifo ; done
If you have a client that connects to a server via plain text protocol such as HTTP or FTP, with this command you can monitor the messages that the client sends to the server. Application level text stream will be dumped on the command line as well as saved in a file called proxy.txt. You have to change 8080 to the local port where you want your client to connect to. Change also 192.168.0.1 to the IP address of the destination server and 80 to the port of the destination server. Then simply point your client to localhost 8080 (or whatever you changed it to). The traffic will be redirected to host 192.168.0.1 on port 80 (or whatever you changed them to). Any requests from the client to the server will be dumped on the console as well as in the file "proxy.txt". Unfortunately the responses from the server will not be dumped.
Sample Output 
Waiting for new event
GET / HTTP/1.1
User-Agent: curl/7.35.0
Host: localhost:8080
Accept: */*

6
By: ynedelchev
2015-01-14 09:26:54
echo mkfifo tee true
2
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What Others Think

You can simplify the command a little by being clever with tee. Drop: tail -f proxy and change tee to: ... | tee -a proxy.txt /dev/stderr | ... The traffic will now be saved to the file and displayed on the screen.
flatcap · 575 weeks and 2 days ago
:-)
flatcap · 575 weeks and 1 day ago

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