protoc-gen-grafbase-subgraph: release 0.3.0

[tomhoule]

Added

• Multiple subgraphs support added. Support for generating multiple GraphQL files based on service annotations:

  • Services can now have a subgraph_name option that maps them to different subgraph files
  • When any service has a subgraph_name, the tool automatically switches to multi-file mode
  • Generated files are named <subgraph_name>.graphql instead of the default schema.graphql
  • Each subgraph file only includes the services and types relevant to that specific subgraph
  • Multiple services can map to the same subgraph
  • Services without subgraph_name in multi-file mode are ignored without warning

• Proto3 optional field support added. The generator now properly handles proto3 optional fields:

  • Non-optional scalar and enum fields in proto3 are rendered as non-nullable (Type!) in GraphQL output types
  • Optional scalar and enum fields are rendered as nullable (Type) in GraphQL output types
  • Message type fields are always nullable regardless of the optional flag
  • Input types remain nullable for all fields
  • The generator now declares support for FEATURE_PROTO3_OPTIONAL to work with proto3 files containing optional fields

• Composite schemas shortcuts added. New protobuf options for simplified composite schemas directives:

  • grafbase.graphql.key option generates @key directives on types
  • grafbase.graphql.lookup option generates @lookup directive on RPC methods
  • grafbase.graphql.argument_is option on RPC methods generates @is directive on the input argument - a shortcut for grafbase.graphql.argument_directives = "@is(field: \"...\")"
  • grafbase.graphql.join_field option generates fields with @require and @grpcMethod directives, with proper type resolution

• Input argument directives added. You can now add GraphQL directives to RPC method input argument, that corresponds to the input of the RPC method, using the grafbase.graphql.argument_directives option on methods.

• Composite schema entity references with @derive added. You can now create federation-style entity references using the grafbase.graphql.derive_field option on messages:

  • Use option (grafbase.graphql.derive_field) = {entity: "User", is: "{ id: user_id }"}; on fields
  • Automatically generates reference fields with @derive and @is directives
  • Creates stub entity types with @key directives if the type is not already defined
  • Supports custom relation field names with the name parameter
  • The @is directive uses the value from the is parameter directly
  • Enables cross-subgraph entity references in federated schemas

• Input argument directives support added. You can now add GraphQL directives to RPC method input arguments using the grafbase.graphql.argument_directives option:

  • Use option (grafbase.graphql.argument_directives) = "@constraint(minLength: 1)"; in method options
  • Supports multiple directives in a single string, separated by spaces
  • Works with both Query and Mutation fields
  • Can be combined with existing method directives

Fixed

• In some scenarios, the plugin would panic because packages were not provided in alphabetical order. This is fixed. (protoc-gen-grafbase-subgraph: fix panics when pushing packages out of order #144)

closes GB-9518

[linear]

GB-9518 Release protoc-gen-grafbase-subgraph