rate limiting http proxy server for JSON-based services.

Features

• HMAC signed keys require no key database for validation.
• Organization ID, Application ID, expiration date, and credit limit can be embedded in keys.
• Translate JSONP requests to non-JSONP requests on the backend.
• Strip cache busting headers and query params.
• Count credits based on IP address or key.
• Provide /credit.json for credits remaining, limit and reset times.

Overview

rl-keygen is used to generate keys

$ ./rl-keygen --secret=12345 --org_id=42 --app_id=1 --expire=1d --credits=240000
XQW2MHYHE3NTC2NDFIAAAAAAAAAQBXBHCIAIBKID
{org_id:42,app_id:1,expires:2012/2/18,flags:0,credits:240000}

$ ./rl-keygen --secret=12345 --org_id=42 --app_id=2 --expire=2000/1/1 --credits=240000
MVA26DOSEN4FD77CFIAAAAAAAABABUAXAEAIBKID
{org_id:42,app_id:2,expires:2000/1/1,flags:0,credits:240000}

rl-proxy sits in front of your caching reverse proxys and application servers

$ ./rl-proxy --backend=localhost:3000 --secret=12345 --reset-duration 24:00:00 --vhost api.example.com --port 8800

$ curl -i http://localhost:8800/credit.json
HTTP/1.1 200 OK
Content-Length: 202
Content-Type: application/json
Date: Sat, 18 Feb 2012 01:20:58 GMT

{"response":{"limit":3600,"reset":1329552000,"refresh_in_secs":23942,"remaining":3600},
"request":{"parameters":{},"response_type":"json","resource":"credit",
"url":"http://api.example.com/credit.json"}}

$ curl -i http://localhost:8800/credit.json?apikey=XQW2MHYHE3NTC2NDFIAAAAAAAAAQBXBHCIAIBKID
HTTP/1.1 200 OK
Content-Length: 254
Content-Type: application/json
Date: Sat, 18 Feb 2012 01:21:23 GMT

{"response":{"limit":240000,"reset":1329552000,"refresh_in_secs":23917,"remaining":240000},
"request":{"parameters":{},"response_type":"json","resource":"credit",
"url":"http://api.example.com/credit.json?apikey=XQW2MHYHE3NTC2NDFIAAAAAAAAAQBXBHCIAIBKID"}}

$ curl -i http://localhost:8800/credit.json?apikey=MVA26DOSEN4FD77CFIAAAAAAAABABUAXAEAIBKID
HTTP/1.1 400 Expired Key
Connection: close
Content-Length: 0
Date: Sat, 18 Feb 2012 01:55:31 GMT

credit-server is the central UDP-based in-memory storage for credits

$ ./credit-server --reset-duration 24:00:00

Dependencies

• cmake >= 2.8
• g++ >= 4.7
• libssl-dev >= 0.9.8
• libboost-dev >= 1.40
• libboost-date-time-dev >= 1.40
• libboost-program-options-dev >= 1.40
• libboost-test-dev >= 1.40
• ragel >= 6.5

Build

$ git clone https://toffaletti@github.com/toffaletti/rl-proxy.git
$ cd rl-proxy
$ git submodule update --init
$ mkdir build; cd build
$ cmake ..
$ make -j4