Extensions allow declarative extensions to "JsRuntime" (ops, state, JS or middleware).
This allows for:
- `op_crates` to be plug-and-play & self-contained, reducing complexity leaked to consumers
- op middleware (like metrics_op) to be opt-in and for new middleware (unstable, tracing,...)
- `MainWorker` and `WebWorker` to be composable, allowing users to extend workers with their ops whilst benefiting from the other infrastructure (inspector, etc...)
In short extensions improve deno's modularity, reducing complexity and leaky abstractions for embedders and the internal codebase.
- Improves op performance.
- Handle op-metadata (errors, promise IDs) explicitly in the op-layer vs
per op-encoding (aka: out-of-payload).
- Remove shared queue & custom "asyncHandlers", all async values are
returned in batches via js_recv_cb.
- The op-layer should be thought of as simple function calls with little
indirection or translation besides the conceptually straightforward
serde_v8 bijections.
- Preserve concepts of json/bin/min as semantic groups of their
inputs/outputs instead of their op-encoding strategy, preserving these
groups will also facilitate partial transitions over to v8 Fast API for the
"min" and "bin" groups
This commit rewrites "dispatch_minimal" into "dispatch_buffer".
It's part of an effort to unify JS interface for ops for both json
and minimal (buffer) ops.
Before this commit "minimal ops" could be either sync or async
depending on the return type from the op, but this commit changes
it to have separate signatures for sync and async ops (just like
in case of json ops).
