Gandolf is an implemention of Raft algorithm which can be used to bring consensus over any database.
This project is consisted of two module gandalf-consensus and gandalf-kvs which is the gandalf own database which can be replaced by others. The overala architecture of project is like the image below.
Each number represent a RaftMessage which is emmited in the system.
| No. | Name |
|---|---|
| 1 | VoteMsg |
| 2 | VoteResp |
| 3 | AppendMsg |
| 4 | AppendResp |
| 5 | ClientReadMsg |
| 6 | ClientWriteMsg |
| 7 | ClientResp |
| 8 | ClientError |
| 9 | SnapMsg |
| 10 | InstallSnapshot |
| 11 | InstallSnapshotResp |
Gandol-consensus is the implemention of Raft algorithm so, it is responsible for bringing consensus to our system. It's also responsible for interacting with database and perform the command on it after the entry got commited. For connecting gandalf to your database you need to implement Parser and Tracker traits for your database, then connect gandalf to your database and point your client to gandalf instead. You can use gandalf.conf files existing in repo to launch a cluster.
Parser trait is responsible for converting client reqeust using the database protocol to somthing understandable for gandalf, so it can decide whether the request is from Read or Write kind. Then it will append the request to log and replicate it to other nodes if it's Write one or just perfrom it if it's a Read.
Tracker trait is responsible for managing the raft log and also comunicating with database.
Gandolf-KVS is a redis like key-value store which is highly ispired from tokio mini-redis and is used as the currently only supported database for Gandolf-onsensus module. It uses RESP for comunicating over tcp with client and also the consesnsus module. This module is consisted of two binary file which gandalf-kvs-server which is used for starting server and, gandalf-kvs which is the client for interacting with the server.
Currently supported commands are:
| Command | Functionality |
|---|---|
| Set | Set a value for a key |
| Get | Retrieve a value for a key |
| Load | Perform multiple set at one or load an snappshot |
| Snap | Take an snappshot |
The overal Architecture of kvs is like image below:
To install gandalf-kvs use:
cargo install gandalf-kvs
To install gandalf use:
cargo install gandalf