Migrate Macro Annotations
juanpedromoreno opened this issue · 2 comments
juanpedromoreno commented
As part of the #290 plan, we need to migrate the current Scalameta macros to the new generation of Macro Annotations.
The current scalameta annotations are:
| Annotation | Scope | Arguments | Description |
|---|---|---|---|
| @service | Trait |
- | Tags the trait as an [RPC] service, in order to derive server and client code (macro expansion). |
| @rpc | Method |
(SerializationType, Compression) |
Indicates that the method is an RPC request. As SerializationType parameter value, Protobuf and Avro are the current supported serialization methods. As Compression parameter value, only Gzip is supported. |
| @stream | Method |
[S <: StreamingType] |
Indicates the method's streaming type: server, client, and bidirectional. Hence, the S type parameter can be ResponseStreaming, RequestStreaming, or BidirectionalStreaming, respectively. |
| @message | Case Class |
- | Tags the case class as an RPC message. |
| @option | Object |
(name: String, value: Any) |
Defines the equivalent headers in .proto files. |
| @outputPackage | Object |
(value: String) |
Defines the package declaration in .proto files, and the namespace tag in .avpr files. |
| @outputName | Object |
(value: String) |
Defines the protocol tag in .avpr files; if missing the idlGen tool will use the source file name (without .scala extension) instead. |
For all these annotations, the only one that is being actually expanded (in terms of expanded code) is @service. The rest of them can be considered as like "anchors"/"settings" used by the @service annotation.
We could consider doing this work creating smaller issues under the feature-branch feature/scalamacros-migration, for example.
L-Lavigne commented
WIP branch: https://github.com/frees-io/freestyle-rpc/commits/MacroConversionWIP (won't compile idlGen module until #298 is done).