update to [email protected]

[Gozala]

This is largest breaking change ucanto has ever introduced, which was motivated by:

1. Implementing receipts per UCAN Invocation spec.
2. Versioning wire protocol to make future breaking changes (which will happen as we implement specs and update between versions) less disruptive.

Here is a non exhaustive task list for this upgrade

1. Invocations will return receipt promises as opposed to results. In the past await invocation.execute(connection) would resolve to the value that had Result type. After update it will resolve to receipts instead which will contain result under .out field.

2. Result type has changed to align with Result in Invocatino spec. ucanto implementation used result that avoided boxing ok branch, and instead error branch had error: true so we used result?.error to differentiate.

   UCAN invocation spec was optimized for different use case and consequently it's Result type looks like type Result<T, X> = { ok: T } | { error: X }. Instead of translating between two all of ucanto has migrated to using later Result type.

   • This meant bunch of code that used to do if (!result?.error) { doSomething(result) } has to change to if (result.ok) { doSomething(result.ok) } else { doSomethingElse(result.error) }

3. Result type on ok branch no longer supports falsy values implying that all the returns that are null or undefined are no longer supported. They changed to {} instead (as in unit type, empty js object). I don't suspect it would break any code but TS will likely report issues in places where null or undefined is success branch of the result type.

4. Capability parser's derivse hook used to return Result<true, Failure>, which changed to Result<{}, Failure>. This is probably where most of the changes will be required, but they are pretty mechanical.

5. Client and server no longer take transport encoder / decoder pairs. Now they take codec field instead that is Transport.OutboundCodec on client and Transport.InboundCodec on the server. That is because they can implement several formats and select one based on content-type and accept headers. Other than passing the different field it should not really affect client / servers.

6. Schema stuff moved from @ucanto/validator to @ucanto/core although validator will still re-export it.

7. To support old clients we have Transport.Legacy codecs which will detect if requests are coming from old clients and transcode responses in a format that those clients expect.