Wasm RPC Protocol Specification

This is the specification of the Protocol Buffers that wasm/node modules will use to setup their RPC interfaces with the central RPC server.

RPC Overview

Borrowed from gRPC

Overall in the MVP of this RPC Framework only the above server and node implimentation will be used. Direct node communication will not be supported.

When a node is initialized it will pass a protobuf describing it's functions and how to call them. Once initialized any other module or direct JS Call can be made to that module.

What the overall structure of wRPC looks like

The blue nodes above represent the wasm modules that wRPC will orchestrate. Eventually wRPC will communicate with more traditional RPC frameworks such as gRPC.

What still needs to be figured out

• Will Data be returned as another proto or as a direct JS value?
• Will the core be written in JS or Wasm?
• What's the best way to make this easy for other Devs to use?
• What are some default failure modes/exceptions?

Proto Descriptions

Initialization Proto

The information that the initialization proto will provide are as follows

• Module name
• How to initialize
• Any extra steps to call functions

• Functions

  • name
  • params
  • return type
  • failure types?
  • async?

• Public info/Data
• Meta data?

Curent Draft

.. literalinclude:: examples/RPC_Module.proto
    :language: proto

Response proto

The idea of this protobuf response is based on Rust's std::option type. Depending on the error and if the remote client can raise an exception wRPC may insert a generic failure.

• Success/Fail

  • if fail why
  • Data

Current Draft

.. literalinclude:: examples/result.proto
    :language: proto

Examples

See the examples folder.

What's next?

See :ref:`js_bindings` for how to interact with JavaScript.