add gorilla and chi helpers

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

chi.go

@@ -0,0 +1,79 @@
+package main
+
+import (
+	"google.golang.org/protobuf/compiler/protogen"
+)
+
+var (
+	chiPackageFiles map[protogen.GoPackageName]struct{}
+)
+
+func (g *Generator) chiGenerate(component string, plugin *protogen.Plugin) error {
+	chiPackageFiles = make(map[protogen.GoPackageName]struct{})
+	for _, file := range plugin.Files {
+		if !file.Generate {
+			continue
+		}
+		if len(file.Services) == 0 {
+			continue
+		}
+		if _, ok := chiPackageFiles[file.GoPackageName]; ok {
+			continue
+		}
+
+		chiPackageFiles[file.GoPackageName] = struct{}{}
+		gname := "micro" + "_" + component + ".pb.go"
+		gfile := plugin.NewGeneratedFile(gname, ".")
+
+		gfile.P("// Code generated by protoc-gen-micro")
+		gfile.P("package ", file.GoPackageName)
+
+		gfile.P()
+		gfile.P("import (")
+		gfile.P(`"context"`)
+		gfile.P(`"fmt"`)
+		gfile.P(`"net/http"`)
+		gfile.P(`"reflect"`)
+		gfile.P(`"strings"`)
+		gfile.P(`chi "github.com/go-chi/chi/v4"`)
+		gfile.P(`middleware "github.com/go-chi/chi/v4/middleware"`)
+		gfile.P(`micro_api "github.com/unistack-org/micro/v3/api"`)
+		gfile.P(")")
+		gfile.P()
+
+		gfile.P("type routeKey struct{}")
+
+		gfile.P("func RouteName(ctx context.Context) (string, bool) {")
+		gfile.P("value, ok := ctx.Value(routeKey{}).(string)")
+		gfile.P("return value, ok")
+		gfile.P("}")
+		gfile.P()
+		gfile.P("func RegisterHandlers(r *chi.Mux, h interface{}, eps []*micro_api.Endpoint) error {")
+		gfile.P("v := reflect.ValueOf(h)")
+		gfile.P("if v.NumMethod() < 1 {")
+		gfile.P(`return fmt.Errorf("handler has no methods: %T", h)`)
+		gfile.P("}")
+		gfile.P("for _, ep := range eps {")
+		gfile.P(`idx := strings.Index(ep.Name, ".")`)
+		gfile.P("if idx < 1 || len(ep.Name) <= idx {")
+		gfile.P(`return fmt.Errorf("invalid api.Endpoint name: %s", ep.Name)`)
+		gfile.P("}")
+		gfile.P("name := ep.Name[idx+1:]")
+		gfile.P("m := v.MethodByName(name)")
+		gfile.P("if !m.IsValid() || m.IsZero() {")
+		gfile.P(`return fmt.Errorf("invalid handler, method %s not found", name)`)
+		gfile.P("}")
+		gfile.P("rh, ok := m.Interface().(func(http.ResponseWriter, *http.Request))")
+		gfile.P("if !ok {")
+		gfile.P(`return fmt.Errorf("invalid handler: %#+v", m.Interface())`)
+		gfile.P("}")
+		gfile.P("for _, method := range ep.Method {")
+		gfile.P("r.With(middleware.WithValue(routeKey{}, ep.Name)).MethodFunc(method, ep.Path[0], rh)")
+		gfile.P("}")
+		gfile.P("}")
+		gfile.P("return nil")
+		gfile.P("}")
+	}
+
+	return nil
+}