Feature

The wasi-runtime-config API has entered Phase 2, I think we can start implementing it.

Benefit

For users, the env API from wasi-cli can currently be used to achieve similar functionality. However, from a semantic standpoint, some configuration items that the runtime wants to pass to the user should be implemented through the config API.

Implementation

Because the wasi-runtime-config API is very simple, its implementation will be quick. However, there is one issue: I'm not sure whether this API should be merged into the current wasi crate or if we should create a separate wasi-runtime-config crate like wasi-http. The current wasi crate essentially only implements the wasi-cli API, so I'm uncertain how we should handle new wasi APIs, eg: wasi-runtime-config or wasi-keyvalue, etc.

If this proposal is accepted, I would be happy to implement this API.

cc @alexcrichton