gem-hunter
Language: Erlang
Erlang Postgres application that uses Poolboy and deals with the database being unavailable
This code is a front end for epgsql that adds a pool (poolboy, for the moment), and code to isolate crashes in the epgsql library: if your database goes down, you probably don't want the rest of the application to fail as well.
Build and start the application with Make:
- Copy and/or rename the file `pgapp.config.sample` into `pgapp.config`
- Enter your configuration data in `pgapp.config`
- Run:
~:$ make
~:$ make run
- To test it, just run:
> pgapp:equery(a_pool_name, "select current_date", []).
where `a_pool_name` is the name of one of the pools in your `pgapp.config` file.
API use: - Simple pool:
application:ensure_all_started(pgapp).
pgapp:connect([{size, 10}, {database, "mydb"}, {username, "foo"}, {password, "bar"}]).
pgapp:equery("select current_date", []),
pgapp:with_transaction(fun() ->
pgapp:squery("update ..."),
pgapp:squery("delete from ..."),
pgapp:equery("select ? from ?", ["*", Table])
end).
- Multi pool:
application:ensure_all_started(pgapp).
pgapp:connect(a_pool_name, [{size, 10}, {database, "mydb"}, {username, "foo"}, {password, "bar"}]).
pgapp:equery(a_pool_name, "select current_date", []).
The equery and squery API's are the same as those of epgsql: https://github.com/epgsql/epgsql
Note: It is still experimental, and is likely to break. The API is not stable!
See [Changelog].