| // Copyright 2016 The LUCI Authors. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| // Command svcdec stands for 'service decorator'. It reads a service interface |
| // XYZServer generated by protoc and generates DecoratedXYZ with this structure: |
| // |
| // type DecoratedXYZ struct { |
| // Service XYZServer |
| // Prelude func(ctx context.Context, methodName string, req proto.Message) (context.Context, error) |
| // } |
| // |
| // DecoratedXYZ has the same methods as XYZServer: they call Prelude before |
| // forwarding the call to the corresponding XYZServer method. |
| // |
| // svcdec is designed to be run through go generate: |
| // |
| // //go:generate svcdec -type GreetServer |
| package main |
| |
| import ( |
| "context" |
| "os" |
| "strings" |
| |
| "go.chromium.org/luci/grpc/internal/svctool" |
| ) |
| |
| func generate(ctx context.Context, a *svctool.GeneratorArgs) error { |
| args := templateArgs{ |
| PackageName: a.PackageName, |
| ExtraImports: a.ExtraImports, |
| } |
| for _, svc := range a.Services { |
| args.Services = append(args.Services, &service{ |
| Service: svc, |
| StructName: "Decorated" + strings.TrimSuffix(svc.TypeName, "Server"), |
| }) |
| } |
| |
| // Execute template. |
| return tmpl.Execute(a.Out, args) |
| } |
| |
| func tool() *svctool.Tool { |
| return &svctool.Tool{Name: "svcdec", OutputFilenameSuffix: "dec"} |
| } |
| |
| func main() { |
| tool().Main(os.Args[1:], generate) |
| } |