Welcome

Director is a production-ready supervisor and manager for Erlang/Elixir processes with focus on speed, performance and flexibility.

Synopsis

According to the Erlang's manual:

A supervisor is a process that supervises other processes called child processes. A child process can either be another supervisor or a worker process. Supervisors are used to build a hierarchical process structure called a supervision tree, a nice way to structure a fault-tolerant application.
In Erlang we tell supervisors to start other processes. Every process has its own options called childspec and its supervisor maybe restart it if it crashed based these options, etc.

Features:

• If a child process crashed, Director can do followings (Depends on childspec):
  • Restart child. In next crash Director will do another action (Depends on childspec)
  • Restart child after time interval. In next crash Director will do another action (Depends on childspec)
  • Delete child from its children.
  • Does nothing and Waits for calling restart_child/2-3 for restarting. In next crash Director will do another action (Depends on childspec)
  • Crash entire supervision tree.
• Director has three database modules for keeping children:
  • director_table_list: An Erlang list. You have to get all children information directly from Director process.
  • director_table_ets: Getting children info is very fast because you can get info directly from table instead of Director process and a number of Director processes can share a table for keeping their children which increases speed of starting and stoping them.
  • director_table_mnesia: Many Director processes in one node or cluster of nodes can share a table for keeping their children. You can get children info directly from table in any node that has a copy of table. With true configuration if one node goes down, your children on that node will restart on other node.
• In Director, your callback module which should give childspecs from its init/1 function, should return an State value too. In termination Director calls YourCallback:terminate(Reason, State).
• A Director process can give response for all API functions of OTP/Supervisor module (for example director:which_children(Pid) =:= supervisor:which_children(Pid)). It has its own interesting API too.
• Director does not write on top of generic behaviors like gen_server, etc. It was written as Erlang special process and it is blazingly fast.
• Director has its own clean debug output for any working state (Standard OTP/sys debug).
• In Director every child can has its own filter for validating its log for starting and crashing.
• Director provides robust and flexible approach for starting and managing many children with one childspec. (Like simple_one_for_one strategy of OTP/Supervisor but better)
• Backend table modules director_table_ets and director_table_mnesia have some useful API for getting children information directly from table.
• Since Director is modular, You can write your own backend table for keeping children and give it to Director for using by implementing director_table behavior. Some test cases are ready for testing your table in /test directory too.

All features not listed here. For more info see wiki or examples directory.
For contributing see CONTRIBUTING.md file.

License

BSD 3-Clause

Author

pouriya.jahanbakhsh@gmail.com

Hex version

18.1.1