Circular Initialization of kv store in contrib/raftexample

[DeamonDev]

What would you like to be added?

In contrib/raftexample/main.go there is definition of kvstore and raftNode:

// raft provides a commit stream for the proposals from the http api
var kvs *kvstore
getSnapshot := func() ([]byte, error) { return kvs.getSnapshot() }
commitC, errorC, snapshotterReady := newRaftNode(*id, strings.Split(*cluster, ","), *join, getSnapshot, proposeC, confChangeC)

kvs = newKVStore(<-snapshotterReady, proposeC, commitC, errorC)

// the key-value http handler will propose updates to raft
serveHTTPKVAPI(kvs, *kvport, confChangeC, errorC)

I see some circularity in these definitions: we use getSnapshot which is defined via (empty) kvs store in order to create raftNode and to use this raft node in order to initialize kvs store. It does not seem to be good design.

I don't have the solution ATM since I'm just getting into codebase, but I would like to start some discussion on that one.

Side question: Wouldn't it be better to rename kvstore to kvStore?

Why is this needed?

Separation of concerns. Code readability would be improved.

[BBQing]

kvs is pointer to kvstore not an empty kvstore
getSnapshot calls getSnapshot on whatever kvs points to

it seems like an example of applied dependency injection

hopefully it helps with readability

also have you tried to read it from the last row?