Add Kubeapps apis docs (#2885)

* Add protoc-gen-openapiv2 into the project

* Configure openapiv2 buf plugin

* Add very initial openapi file

* Add openapi annotations

* Add generated files

* Add generated files

* Add more docs

* Rename svc from the plugins

* Remove base_path

* Fix leftover

* Changes in go after rename in proto

cmd/kubeapps-apis/Makefile

@@ -26,7 +26,8 @@ cli-dependencies:
 	go get \
 		github.com/spf13/cobra/cobra \
 		google.golang.org/grpc/cmd/protoc-gen-go-grpc \
-		google.golang.org/protobuf/cmd/protoc-gen-go
+		google.golang.org/protobuf/cmd/protoc-gen-go \
+		github.com/grpc-ecosystem/grpc-gateway/v2/protoc-gen-openapiv2 
 
 # Not sure if it's worth having targets for buf, but at least the targets can
 # be tooling agnostic.

cmd/kubeapps-apis/buf.gen.yaml

@@ -12,3 +12,14 @@ plugins:
     out: gen
     opt:
       - module=github.com/kubeapps/kubeapps/cmd/kubeapps-apis/gen
+  # Consider migrating to openapiv3 once ready
+  # https://github.com/grpc-ecosystem/grpc-gateway/pull/2147
+  - name: openapiv2
+    out: docs
+    strategy: all
+    opt:
+      - allow_merge=true
+      - merge_file_name=kubeapps-apis
+      - allow_repeated_fields_in_body=true
+      # - generate_unbound_methods=true # have to re-check it
+      # - json_names_for_fields=false # have to re-check it

cmd/kubeapps-apis/buf.lock

@@ -4,6 +4,13 @@ deps:
     owner: beta
     repository: googleapis
     branch: main
-    commit: aced890b7e944f9ca174481ad810ca5f
-    digest: b1-guLHfQhGOhlEA-QaPyQLoT-ZVFGJkRkluWgkzPT0ma0=
-    create_time: 2021-03-04T14:52:47.094456Z
+    commit: 2e73676eef8642dfba4ed782b7c8d6fe
+    digest: b1-vB11w98W2vFtEP4Veknm56Pi6DU6MpOuocESiOzvbqw=
+    create_time: 2021-04-26T14:55:30.644663Z
+  - remote: buf.build
+    owner: grpc-ecosystem
+    repository: grpc-gateway
+    branch: main
+    commit: d19475fa22444a289c46af009acce62c
+    digest: b1-_zhDPyr_Ctc1QRAKuad6_0xvoyPd6QaB22ldm9gzS0Q=
+    create_time: 2021-04-26T15:19:26.742789Z