feat: RPC Versioning

[akhercha]

Pull Request type

Please add the labels corresponding to the type of changes your PR introduces:

• Feature

What is the current behavior?

Resolves: #NA

What is the new behavior?

Introduction of versions for our RPC API.

Versions are defined in the mc-rpc::versions module, organized as follow:

versions
├── mod.rs
└── v0_7_1
    ├── mod.rs
    ├── api.rs               # contains the API definition of the current version
    └── methods              # contains all the methods implementation
         ├── mod.rs
         ├── read/
         ├── trace/
         └── write/

All the implementations are then merged in our RpcModule in the versioned_rpc_api function.

Methods will be version-prefixed to avoid collisions, for example:

• starknet_V0_7_1_blockNumber,
• starknet_V0_8_0_blockNumber
• etc...

The "routing" is done in the VersionMiddlewareLayer middleware, where depending on the version provided in the route by the request's user, we forward to the right method.

If no version is provided, the latest RPC version available is used, defined in RpcVersion::RPC_VERSION_LATEST.

Does this introduce a breaking change?

No

Possible improvement

I don't like the current process of adding a new version ; it is:

1. Create a new constant in the RpcVersion primitive, like: pub const RPC_VERSION_0_7_1: RpcVersion = RpcVersion([0, 7, 1]);
2. Add it in the SUPPORTED_RPC_VERSIONS array,
3. Add the version API + implementation in the mc-rpc::versions module,
4. Add the module when merging the API methods:

pub fn versioned_rpc_api(starknet: &Starknet, read: bool, write: bool, trace: bool) -> anyhow::Result<RpcModule<()>> {
    let mut rpc_api = RpcModule::new(());

    merge_rpc_versions!(
        rpc_api, starknet, read, write, trace,
        v0_7_1, // We can add new versions by adding the version module below
        // , v0_8_0 (for example)
    );
// ...

Lot of dependency between objects, the middleware also uses the SUPPORTED_RPC_VERSIONS array for routing.

It is fine though because we don't have new versions everyday, that's an uncommon event.
But happy to hear your suggestions!

[github-actions]

Coverage report

The coverage rate is 67.64327108821635%

74% of new lines are covered.

Diff Coverage details (click to unfold)

crates/node/src/service/rpc/middleware.rs

48.33333333333333% of new lines are covered

crates/client/rpc/src/versions/v0_7_1/methods/read/lib.rs

0.0% of new lines are covered

crates/client/rpc/src/versions/v0_7_1/api.rs

100.0% of new lines are covered

crates/proc-macros/src/lib.rs

88.70967741935485% of new lines are covered

crates/client/rpc/src/test_utils.rs

0.0% of new lines are covered

crates/node/src/service/rpc.rs

100.0% of new lines are covered

crates/node/src/main.rs

100.0% of new lines are covered

crates/node/src/service/rpc/server.rs

100.0% of new lines are covered

crates/primitives/chain_config/src/rpc_version.rs

87.73584905660377% of new lines are covered

crates/client/rpc/src/lib.rs

75.0% of new lines are covered

[antiyro]

Approving this since it has been reviewed correctly in #242