Sqerl/Squirrel Market Trade Processor. Accepts incoming currency trade information encoded in JSON through POST to the trade controller and records it in the configured MySQL database after decoding and validation. Implements two-tier rate limiting; all requests can be rate-limited based on IP Address while trade submissions can be rate-limited based on the user ID of the trade.
After successful storage an event is fired through a gen_event manager. Clients connected via web socket to the feed controller will have trade data sent to them as they are processed. For an example of a trade feed display front-end based on Google's WebGL Globe, see Peacock.
- Erlang HiPE R17+
- MySQL Server
git clone [email protected]:wrren/sqerl.git
cd sqerl
make
./_rel/sqerl_release/bin/sqerl_release start
Run Unit Tests:
make ct
Edit src/sqerl.app.src to set configuration values. Listen port, database connection and rate limiting options can be set. Changes to this file will only take effect after rebuilding the app using make.
Rate limiting factors indicates the rate limiters and the order in which they are applied. Both ip and user settings share the configured window length and request limit settings. Set the sqerl_rate_limit_factors settings to an empty list ([]) to disable rate limiting.
Bootstrap your MySQL database with the trade schema using the sqerl.sql file included in the repository.
mysql -u <user> -p <database> < sqerl.sql
Trade data should be POST'ed to the /trade route with a content type of application/json. To test trade recording, use the request.sh script included with the repo. The first argument to the script is the trade submission URL. When running on the same server with the default listen port, the address would be http://localhost:8080/trade. Request frequency is set to 10/s.
To receive trade submission events over websocket, connect to the /feed route. If using peacock, edit public/app/js/config.js and set the websocket URL. Example configuration:
var config = { server: "ws://example.com:8080/feed", max_feed_items: 30 };