Lasp PG
=======================================================
[](https://travis-ci.org/lasp-lang/lasp_pg)
Eventually consistent process registry, the spirtual successor to [Riak PG](https://github.com/cmeiklejohn/riak_pg).
## Usage
What are groups?
```erlang
-type group() :: term().
```
Join a process to a group (no need to pre-declare)
```erlang
lasp_pg:join(group(), pid()) -> ok.
```
What about removing?
```erlang
lasp_pg:leave(group(), pid()) -> ok.
```
You can also return the members.
```erlang
lasp_pg:members(group()) -> {ok, sets:set(pid())}.
```
## Clustering
Use the ```lasp_peer_service``` API to join and leave nodes:
```erlang
lasp_peer_service:join({Name, IP, Port}).
```
## Partisan
Our [Partisan](http://github.com/lasp-lang/partisan) library drives what
distribution facility you use: you can use the custom HyParView inspired
backend, which scales to 512+ node Erlang clusters, or fall back to
client/server or full-mesh with distributed Erlang.
This can be configured using the following command, before the Partisan
application is started:
```erlang
partisan_config:set(partisan_peer_service_manager, partisan_hyparview_peer_service_manager).
```
Available options are: ```partisan_client_server_peer_service_manager```, ```partisan_default_peer_service_manager``` or ```partisan_hyparview_peer_service_manager```.
## Replication
Lasp PG uses the underlying Lasp KV store, which only has in-memory
persistence currently, but a configurable API so that can be changed to
use either RocksDB or LevelDB. Lasp KV is fully replicated across all
nodes, but partial replication is coming soon.
