mirror of
https://github.com/zebrajr/react.git
synced 2026-01-15 12:15:22 +00:00
6e169fc65d
It can be efficient to accept raw string chunks to pass through a stream instead of encoding them into a binary copy first. Previously our Flight parsers didn't accept receiving string chunks. That's partly because we sometimes need to encode binary chunks anyway so string only transport isn't enough but some chunks can be strings. This adds a partial ability for chunks to be received as strings. However, accepting strings comes with some downsides. E.g. if the strings are split up we need to buffer it which compromises the perf for the common case. If the chunk represents binary data, then we'd need to encode it back into a typed array which would require a TextEncoder dependency in the parser. If the string chunk represents a byte length encoded string we don't know how many unicode characters to read without measuring them in terms of binary - also requiring a TextEncoder. This PR is mainly intended for use for pass-through within the same memory. We can simplify the implementation by assuming that any string chunk is passed as the original chunk. This requires that the server stream config doesn't arbitrarily concatenate strings (e.g. large strings should not be concatenated which is probably a good heuristic anyway). It also means that this is not suitable to be used with for example receiving string chunks on the client by passing them through SSR hydration data - except if the encoding that way was only used with chunks that were already encoded as strings by Flight. Web streams mostly just work on binary data anyway so they can't use this. In Node.js streams we concatenate precomputed and small strings into larger buffers. It might make sense to do that using string ropes instead. However, in the meantime we can at least pass large strings that are outside our buffer view size as raw strings. There's no benefit to us eagerly encoding those. Also, let Node accept string chunks as long as they're following our expected constraints. This lets us test the mixed protocol using pass-throughs. This can also be useful when the RSC server is in the same environment as the SSR server as they don't have to go from strings to typed arrays back to strings. Now we can also use this in the pass-through used in renderToMarkup. This lets us avoid the dependency on TextDecoder/TextEncoder in that package.
The error code system substitutes React's error messages with error IDs to provide a better debugging support in production. Check out the blog post here.
codes.jsoncontains the mapping from IDs to error messages. This file is generated by the Gulp plugin and is used by both the Babel plugin and the error decoder page in our documentation. This file is append-only, which means an existing code in the file will never be changed/removed.extract-errors.jsis an node script that traverses our codebase and updatescodes.json. You can test it by runningyarn extract-errors. It works by crawling the build artifacts directory, so you need to have either run the build script or downloaded pre-built artifacts (e.g. withyarn download build). It works with partial builds, too.transform-error-messagesis a Babel pass that rewrites error messages to IDs for a production (minified) build.