[Rust][Compiler] Add Configuration/Document Query Persisting in the OSS Compiler

[alunyov]

• Add config to SingleProjectConfigFile
• Add documentation #3660

[maraisr]

This in order to support @preloadable in OSS? Or more not to support the FormData upload mechanism, and be back to the JS version of json files?

[alunyov]

In the rust version, we decided to expose the persisting mechanism we are using internally. Basically, we're sending (HTTP post) full query text to the API endpoint, that knows how/where to save the query text, and it can return a persisted query ID for it.

See: https://github.com/facebook/relay/blob/main/compiler/crates/persist-query/src/lib.rs#L53-L72

This task is just to add documentation for it and expose it via SingleProjectConfigFile, here: https://github.com/facebook/relay/blob/main/compiler/crates/relay-compiler/src/config.rs#L630

And yeah, with persisted query IDs @preloadable can generate $parameters files that can be used with entry-points. But maybe there is something else we need to add.

[wongmjane]

It’s great to know the Rust version of the Relay compiler has RemotePersister for persisting queries remotely:

https://github.com/facebook/relay/blob/87696f9cbf61739cb7474be447cf1d88e6eec0c8/compiler/crates/relay-compiler/src/remote_persister.rs

Will there still be a way to locally persist the queries (e.g. writing into a JSON file locally like the JS version)? Thanks!

Update: @vincentriemer is working on it #3666 🚀

[alunyov]

Thanks @wongmjane!

Currently, we don't have this, but it should not be difficult change to add support for this.
This new JSON local persister just needs to implement the OperationPersister trait.

We always welcome contributions and are happy to review and merge them :-)