Generate protobuf type-conversion functions (#118)

Author: pglass

Makefile

@@ -79,14 +79,16 @@ generate-rpcwrappers:
 	rm -rf $(GENRPCWRAPPERS_DIR)/*_gen.go
 	cd $(GENRPCWRAPPERS_DIR); go run .  -service frontend -license_file ../../../LICENSE
 	cp $(GENRPCWRAPPERS_DIR)/lazy_client_gen.go client/frontend/lazy_client_gen.go
+	mkdir -p proto/compat
+	cp $(GENRPCWRAPPERS_DIR)/conversion_gen.go proto/compat/frontend_conversion_gen.go
 
 	rm -rf ./cmd/tools/genrpcwrappers/*_gen.go
 	cd $(GENRPCWRAPPERS_DIR); go run .  -service admin -license_file ../../../LICENSE
 	cp ./cmd/tools/genrpcwrappers/lazy_client_gen.go client/admin/lazy_client_gen.go
+	cp $(GENRPCWRAPPERS_DIR)/conversion_gen.go proto/compat/admin_conversion_gen.go
 
 	rm -rf ./cmd/tools/genrpcwrappers/*_gen.go
-
-	go fmt ./client/...
+	go fmt ./client/... ./proto/compat/...
 
 test: generate-test-certs
 	go test $(TEST_ARG) ./...

client/admin/lazy_client_gen.go

@@ -1,12 +1,51 @@
 package main
 
-import "io"
+import (
+	"io"
+)
 
 var (
 	lazyClientMap = map[string]string{
 		"admin":    "GetAdminClient",
 		"frontend": "GetWorkflowServiceClient",
 	}
+
+	ignoreMethodsNotIn122 = map[string]bool{
+		// adminservice methods
+		"AddTasks":                            true,
+		"CancelDLQJob":                        true,
+		"DeepHealthCheck":                     true,
+		"DescribeDLQJob":                      true,
+		"DescribeTaskQueuePartition":          true,
+		"ForceUnloadTaskQueuePartition":       true,
+		"GenerateLastHistoryReplicationTasks": true,
+		"GetDLQTasks":                         true,
+		"GetWorkflowExecutionRawHistory":      true,
+		"ImportWorkflowExecution":             true,
+		"ListQueues":                          true,
+		"MergeDLQTasks":                       true,
+		"PurgeDLQTasks":                       true,
+		"SyncWorkflowState":                   true,
+
+		// workflowservice
+		"DescribeDeployment":             true,
+		"ExecuteMultiOperation":          true,
+		"GetCurrentDeployment":           true,
+		"GetDeploymentReachability":      true,
+		"GetWorkerVersioningRules":       true,
+		"ListDeployments":                true,
+		"PauseActivityById":              true,
+		"PollNexusTaskQueue":             true,
+		"ResetActivityById":              true,
+		"RespondNexusTaskCompleted":      true,
+		"RespondNexusTaskFailed":         true,
+		"SetCurrentDeployment":           true,
+		"ShutdownWorker":                 true,
+		"UnpauseActivityById":            true,
+		"UpdateActivityOptionsById":      true,
+		"UpdateWorkerVersioningRules":    true,
+		"UpdateWorkflowExecutionOptions": true,
+	}
 )
 
 func init() {
@@ -59,3 +98,43 @@ func (c *lazyClient) {{.Method}}(
 }
 `)
 }
+
+func generate122ConversionCode(w io.Writer, service service) {
+	writeTemplatedCode(w, service, `
+package compat
+import (
+	svc "{{.ServicePackagePath}}"
+	svc122 "{{.ServicePackagePath122}}"
+	"github.com/temporalio/s2s-proxy/common"
+)
+
+// {{.ServiceNameTitle}}ConvertTo122 accepts a protobuf type and returns
+// the corresponding gogo-based protobuf type from Temporal v1.22.
+func {{.ServiceNameTitle}}ConvertTo122(vAny any) (common.Marshaler, bool) {
+	switch vAny.(type) {
+`)
+
+	writeTemplatedMethods122(w, service, "conversion", `
+case *svc.{{.Method}}Response:
+	return &svc122.{{.Method}}Response{}, true
+case *svc.{{.Method}}Request:
+	return &svc122.{{.Method}}Request{}, true
+`)
+
+	writeTemplatedCode(w, service, `}
+	return nil, false
+}
+`)
+}
+
+func writeTemplatedMethods122(w io.Writer, service service, impl string, text string) {
+	sType := service.clientType.Elem()
+	for n := 0; n < sType.NumMethod(); n++ {
+		m := sType.Method(n)
+		if ignoreMethodsNotIn122[m.Name] {
+			continue
+		}
+
+		writeTemplatedMethod(w, service, impl, m, text)
+	}
+}

client/frontend/lazy_client_gen.go

@@ -156,9 +156,13 @@ func panicIfErr(err error) {
 }
 
 func writeTemplatedCode(w io.Writer, service service, text string) {
+	pkgPath := service.clientType.Elem().PkgPath()
+	titleCase := strings.ToUpper(service.name[:1]) + service.name[1:]
 	panicIfErr(template.Must(template.New("code").Parse(text)).Execute(w, map[string]string{
-		"ServiceName":        service.name,
-		"ServicePackagePath": service.clientType.Elem().PkgPath(),
+		"ServiceName":           service.name,
+		"ServicePackagePath":    pkgPath,
+		"ServiceNameTitle":      titleCase,
+		"ServicePackagePath122": strings.Replace(pkgPath, "go.temporal.io", "github.com/temporalio/s2s-proxy/proto/1_22", 1),
 	}))
 }
 
@@ -409,21 +413,13 @@ func makeGetMatchingClient(reqType reflect.Type) string {
 	panic("I don't know how to get a client from a " + t.String())
 }
 
-func writeTemplatedMethod(w io.Writer, service service, impl string, m reflect.Method, text string) {
-	key := fmt.Sprintf("%s.%s.%s", impl, service.name, m.Name)
-	if ignoreMethod[key] {
-		return
-	}
-
-	mt := m.Type // should look like: func(context.Context, request reqType, opts []grpc.CallOption) (respType, error)
-	if !mt.IsVariadic() ||
-		mt.NumIn() != 3 ||
-		mt.NumOut() != 2 ||
-		mt.In(0).String() != "context.Context" ||
-		mt.Out(1).String() != "error" {
-		panic(key + " doesn't look like a grpc handler method")
-	}
+func methodKey(impl string, svc service, m reflect.Method) string {
+	return fmt.Sprintf("%s.%s.%s", impl, svc.name, m.Name)
+}
 
+func writeTemplatedMethod(w io.Writer, service service, impl string, m reflect.Method, text string) {
+	key := methodKey(impl, service, m)
+	mt := m.Type
 	reqType := mt.In(1)
 	respType := mt.Out(0)
 
@@ -460,7 +456,22 @@ func writeTemplatedMethod(w io.Writer, service service, impl string, m reflect.M
 func writeTemplatedMethods(w io.Writer, service service, impl string, text string) {
 	sType := service.clientType.Elem()
 	for n := 0; n < sType.NumMethod(); n++ {
-		writeTemplatedMethod(w, service, impl, sType.Method(n), text)
+		m := sType.Method(n)
+		key := methodKey(impl, service, m)
+		if ignoreMethod[key] {
+			continue
+		}
+
+		// should look like: func(context.Context, request reqType, opts []grpc.CallOption) (respType, error)
+		mt := m.Type
+		if !mt.IsVariadic() ||
+			mt.NumIn() != 3 ||
+			mt.NumOut() != 2 ||
+			mt.In(0).String() != "context.Context" ||
+			mt.Out(1).String() != "error" {
+			panic(key + " doesn't look like a grpc handler method")
+		}
+		writeTemplatedMethod(w, service, impl, m, text)
 	}
 }
 
@@ -675,4 +686,6 @@ func main() {
 	if svc.name == "admin" {
 		callWithFile(generateACLServer, svc, "acl_server", "")
 	}
+
+	callWithFile(generate122ConversionCode, svc, "conversion", "")
 }

cmd/tools/genrpcwrappers/extra.go

@@ -0,0 +1,6 @@
+package common
+
+type Marshaler interface {
+	Marshal() ([]byte, error)
+	Unmarshal([]byte) error
+}