Net tools - proxy servers

Description:

Jetty is a powerful embedded web container / web server. Among many other features it has support for proxies. This is some small proxy utilities based on Jettys proxy capability. Note that it is less than a hundred lines of mine on top of Jetty per proxy, so my contribution is pretty small.

Proxies:

NullProxy: proxy that just proxies without doing anything special
LimitingProxy: proxy that limit number of concurrent requests
SlowProxy: proxy that provides an artificial delay in response
HeaderProxy: proxy that injects headers into request
LogProxy: LogProxy that logs requests and responses

Installation:

System requirements:

Java 5 or newer.

Installation Windows:

cd <location>
unzip proxy-bin
unzip win

Installation VMS:

set def <location>
unzip proxy-bin
set file/attr=rfm:stmlf *.jar
unzip -aa vms

Run:

Run Windows:

<location>null ...

or:

<location>limit ...

or:

<location>slow ...

or:

<location>header ...

or:

<location>log ...

Run VMS:

@<location>null ...

or:

@<location>limit ...

or:

@<location>slow ...

or:

@<location>header ...

or:

@<location>log ...

Usage:

NullProxy:

Standard transperent proxy. This can be useful for network/port reasons.

Command:

null listenport forwardurl_prefix

Arguments:

listenport: the local port the proxy will listen on
forwardurl_prefix: prefix for URL that will be requested

Example:

null 10080 http://localhost:80

This proxy will:

listen on port 10080
forward /* to http://localhost:80/*

LimitingProxy:

Limit number of concurrent requests for some resources. This can be useful to protect the server from being overwhelmed by requests.

Command:

limit listenport forwardurl_prefix targetpath_prefix concurrencylimit busyurl verbose

Arguments:

listenport: the local port the proxy will listen on
forwardurl_prefix: prefix for URL that will be requested
targetpath_prefix: path prefix of what will be limited (use / for all)
concurrencylimit: max. concurrent requests
busyurl: URL requested in case concurrencylimit exceeded
verbose: verbosity: 0 => no output, 1 => output requests resulting in busy, 2 => output all request

Example:

limit 10080 http://localhost:80 /script 10 http://localhost/busy.html 1

This proxy will:

listen on port 10080
forward /* to http://localhost:80/*
limit requests for /script/* to max. 10 concurrent
if exceeded forward to http://localhost/busy.html
log all busy requests

SlowProxy:

Slow down response to some resources. This can be useful to simulate slow network.

Command:

slow listenport forwardurl_prefix targetpath_prefix delay

Arguments:

listenport: the local port the proxy will listen on
forwardurl_prefix: prefix for URL that will be requested
targetpath_prefix: path prefix of what will be slowed down (use / for all)
delay: slow down delay in milliseconds

Example:

slow 10080 http://localhost:80 /foo 500

This proxy will:

listen on port 10080
forward /* to http://localhost:80/*
slow down requests for /foo/* with a 500 millisecond delay

HeaderProxy:

Modify headers in request. This can be useful to insert something the server requires.

Command:

header listenport forwardurl_prefix targetpath_prefix hdr1 hdrval1 ... hdrn hdrvaln

Arguments:

listenport: the local port the proxy will listen on
forwardurl_prefix: prefix for URL that will be requested
targetpath_prefix: path prefix of what will be modified (use / for all)
hdr1: header #1 to modify/add
hdrval1: header #1 value
...: ...
...: ...
hdrn: header #n to modify/add
hdrvaln: header #n value

Example:

header 10080 http://localhost:80 /bar User-Agent "None of your business" X-Dummy Nothing

This proxy will:

listen on port 10080
forward /* to http://localhost:80/*
modify requests for /bar/* so that they have headers:
```
User-Agent: None of your business
X-Dummy: Nothing
```

LogProxy:

Logs requests and responses for some resources. This can be useful for troubleshooting.

Note that it just logs headers and byte count for body - not full body (that would be problematic for some types of content).

Command:

log listenport forwardurl_prefix targetpath_prefix logfile

Arguments:

listenport: the local port the proxy will listen on
forwardurl_prefix: prefix for URL that will be requested
targetpath_prefix: path prefix of what will be logged (use / for all)
logfile: file with log output

Important: requests will be serialized to avoid messing up log output - this will impact performance.

Example:

log 10080 http://localhost:80 /foobar foobar.log

This proxy will:

listen on port 10080
forward /* to http://localhost:80/*
log requests and responses for /foobar/* tp foobar.log

License:

Both my code and the Jetty code are available under Apache 2.0 license.