Addition of custom http grpc handlers to support reverse proxy by Ori…

…on (#170) * add code handlers * add customCodec and unknown service handler to grpc handler * add custom http handler * add grpc server options only if they are not nil * using encoding.codec as grpc.codec is deprecated * removing custom codec as Orion server option as it was not necessary * handlers name refactoring * add handlers in orion config * adding handlers via options * passing pointer of notfoundhandler * removing http handler option * adding server options in GetDefaultServer * Apply suggestions from code review Co-authored-by: Benjamin Heng <[email protected]> Co-authored-by: Ganesh <[email protected]> Co-authored-by: Benjamin Heng <[email protected]> Co-authored-by: Achi Chen <[email protected]>
carousell · Jul 22, 2022 · d30c4e5 · d30c4e5
1 parent fae579f
commit d30c4e5
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Showing 3 changed files with 53 additions and 11 deletions.
diff --git a/orion/config.go b/orion/config.go
@@ -4,7 +4,6 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
-
 	"github.com/afex/hystrix-go/hystrix"
 	"github.com/spf13/viper"
 

diff --git a/orion/core.go b/orion/core.go
@@ -69,10 +69,11 @@ type middlewareInfo struct {
 
 //DefaultServerImpl provides a default implementation of orion.Server this can be embedded in custom orion.Server implementations
 type DefaultServerImpl struct {
-	config Config
-	mu     sync.Mutex
-	wg     sync.WaitGroup
-	inited bool
+	config                    Config
+	mu                        sync.Mutex
+	wg                        sync.WaitGroup
+	grpcUnknownServiceHandler grpc.StreamHandler
+	inited                    bool
 
 	services     map[string]*svcInfo
 	encoders     map[string]*encoderInfo
@@ -263,6 +264,7 @@ func (d *DefaultServerImpl) buildHandlers() []*handlerInfo {
 			CommonConfig: handlers.CommonConfig{
 				DisableDefaultInterceptors: d.config.DisableDefaultInterceptors,
 			},
+			UnknownServiceHandler: d.grpcUnknownServiceHandler,
 		}
 		handler := grpcHandler.NewGRPCHandler(config)
 		hlrs = append(hlrs, &handlerInfo{
@@ -498,8 +500,14 @@ func (d *DefaultServerImpl) Stop(timeout time.Duration) error {
 }
 
 //GetDefaultServer returns a default server object that can be directly used to start orion server
-func GetDefaultServer(name string) Server {
-	return GetDefaultServerWithConfig(BuildDefaultConfig(name))
+func GetDefaultServer(name string, opts ...DefaultServerOption) Server {
+	server := &DefaultServerImpl{
+		config: BuildDefaultConfig(name),
+	}
+	for _, opt := range opts {
+		opt.apply(server)
+	}
+	return server
 }
 
 //GetDefaultServerWithConfig returns a default server object that uses provided configuration
@@ -508,3 +516,29 @@ func GetDefaultServerWithConfig(config Config) Server {
 		config: config,
 	}
 }
+
+type DefaultServerOption interface {
+	apply(*DefaultServerImpl)
+}
+
+// WithGrpcUnknownHandler returns a DefaultServerOption which sets
+// UnknownServiceHandler option in grpc server
+func WithGrpcUnknownHandler(grpcUnknownServiceHandler grpc.StreamHandler) DefaultServerOption {
+	return newFuncDefaultServerOption(func(h *DefaultServerImpl) {
+		h.grpcUnknownServiceHandler = grpcUnknownServiceHandler
+	})
+}
+
+type funcDefaultServerOption struct {
+	f func(options *DefaultServerImpl)
+}
+
+func (fdso *funcDefaultServerOption) apply(ds *DefaultServerImpl) {
+	fdso.f(ds)
+}
+
+func newFuncDefaultServerOption(f func(options *DefaultServerImpl)) *funcDefaultServerOption {
+	return &funcDefaultServerOption{
+		f: f,
+	}
+}
diff --git a/orion/handlers/grpc/grpc.go b/orion/handlers/grpc/grpc.go
@@ -10,11 +10,13 @@ import (
 	"github.com/carousell/Orion/utils/log"
 	grpc_prometheus "github.com/grpc-ecosystem/go-grpc-prometheus"
 	"google.golang.org/grpc"
+
 )
 
 // Config is the configuration for GRPC Handler
 type Config struct {
 	handlers.CommonConfig
+	UnknownServiceHandler grpc.StreamHandler
 }
 
 //NewGRPCHandler creates a new GRPC handler
@@ -31,10 +33,17 @@ type grpcHandler struct {
 
 func (g *grpcHandler) init() {
 	if g.grpcServer == nil {
-		g.grpcServer = grpc.NewServer(
-			grpc.UnaryInterceptor(g.grpcInterceptor()),
-			grpc.StreamInterceptor(g.grpcStreamInterceptor()),
-		)
+		var opts []grpc.ServerOption
+		if g.grpcInterceptor() != nil {
+			opts = append(opts, grpc.UnaryInterceptor(g.grpcInterceptor()))
+		}
+		if g.grpcStreamInterceptor() != nil {
+			opts = append(opts, grpc.StreamInterceptor(g.grpcStreamInterceptor()))
+		}
+		if g.config.UnknownServiceHandler != nil {
+			opts = append(opts, grpc.UnknownServiceHandler(g.config.UnknownServiceHandler))
+		}
+		g.grpcServer = grpc.NewServer(opts...)
 	}
 	if g.middlewares == nil {
 		g.middlewares = handlers.NewMiddlewareMapping()