racl: redis-backed access control lists

Status

racl stores explicit access permissions in redis. You can query who has which access levels as well as do blind checks for allowed/deny on specific features you specify.

Usage

1. Determine the types of properties you want to control e.g. user can be granted read, write, send, flag, moderate permissions
2. Add those permissions to a module. See src/racl_content.lfe for an example.
   • Basically, you use a macro that defines a module for you. (defacl my_racl_module_name (property1 property2 property3) ((export all)) ((defun extra_functions () 'hi) (defun more_functions () 'there)))
3. Compile. (rebar compile)
4. Your new module has five functions defined per property. For example, if your module is named "racl_forum" with a property named "flag", your functions are:
   • racl_forum:flag(ErServerName, RedisKey, IdOfUserForRequestedAccess)
     • Verifies the IdOfUserForRequestedAccess is authorized for the 'flag' property of RedisKey
   • racl_forum:is_flag(ErServerName, RedisKey)
     • Returns a list of user ids granted 'flag' access
   • racl_forum:allowed_flag(ErServerName, RedisKey)
     • Returns a list of user ids granted 'flag' access
   • racl_forum:denied_flag(ErServerName, RedisKey)
     • Returns a list of user ids denied 'flag' access
   • racl_forum:add_flag(ErServerName, RedisKey, UserIdToAllow)
     • Enable UserIdToAllow 'flag' access on RedisKey
   • racl_forum:remove_flag(ErServerName, RedisKey, UserIdToDeny)
     • Deny UserIdToDeny 'flag' access on RedisKey

Building

    rebar get-deps
    rebar compile

Testing

The tests here are mostly symbolic and kinda useless.

    rebar eunit skip_deps=true suite=racl

Next Steps

Create better examples of usage.