interceptors: add chain interceptors

Signed-off-by: Adphi <philippe.adrien.nousse@gmail.com>

interceptors/chain/chain.go

@@ -0,0 +1,126 @@
+package chain
+
+import (
+	grpc_middleware "github.com/grpc-ecosystem/go-grpc-middleware"
+	"google.golang.org/grpc"
+
+	"go.linka.cloud/grpc/interceptors"
+)
+
+type Option func(*chain)
+
+func WithInterceptors(i ...interceptors.Interceptors) Option {
+	return func(c *chain) {
+		for _, i := range i {
+			if i := i.UnaryServerInterceptor(); i != nil {
+				c.usi = append(c.usi, i)
+			}
+			if i := i.StreamServerInterceptor(); i != nil {
+				c.ssi = append(c.ssi, i)
+			}
+			if i := i.UnaryClientInterceptor(); i != nil {
+				c.uci = append(c.uci, i)
+			}
+			if i := i.StreamClientInterceptor(); i != nil {
+				c.sci = append(c.sci, i)
+			}
+		}
+	}
+}
+
+func WithServerInterceptors(si ...interceptors.ServerInterceptors) Option {
+	return func(c *chain) {
+		for _, i := range si {
+			if i := i.UnaryServerInterceptor(); i != nil {
+				c.usi = append(c.usi, i)
+			}
+			if i := i.StreamServerInterceptor(); i != nil {
+				c.ssi = append(c.ssi, i)
+			}
+		}
+	}
+}
+
+func WithClientInterceptors(ci ...interceptors.ClientInterceptors) Option {
+	return func(c *chain) {
+		for _, i := range ci {
+			if i := i.UnaryClientInterceptor(); i != nil {
+				c.uci = append(c.uci, i)
+			}
+			if i := i.StreamClientInterceptor(); i != nil {
+				c.sci = append(c.sci, i)
+			}
+		}
+	}
+}
+
+func WithUnaryServerInterceptors(usi ...grpc.UnaryServerInterceptor) Option {
+	return func(c *chain) {
+		for _, i := range usi {
+			if i != nil {
+				c.usi = append(c.usi, i)
+			}
+		}
+	}
+}
+
+func WithStreamServerInterceptors(ssi ...grpc.StreamServerInterceptor) Option {
+	return func(c *chain) {
+		for _, i := range ssi {
+			if i != nil {
+				c.ssi = append(c.ssi, i)
+			}
+		}
+	}
+}
+
+func WithUnaryClientInterceptors(uci ...grpc.UnaryClientInterceptor) Option {
+	return func(c *chain) {
+		for _, i := range uci {
+			if i != nil {
+				c.uci = append(c.uci, i)
+			}
+		}
+	}
+}
+
+func WithStreamClientInterceptors(sci ...grpc.StreamClientInterceptor) Option {
+	return func(c *chain) {
+		for _, i := range sci {
+			if i != nil {
+				c.sci = append(c.sci, i)
+			}
+		}
+	}
+}
+
+func New(opts ...Option) interceptors.Interceptors {
+	c := &chain{}
+	for _, o := range opts {
+		o(c)
+	}
+	return c
+}
+
+type chain struct {
+	usi []grpc.UnaryServerInterceptor
+	ssi []grpc.StreamServerInterceptor
+	uci []grpc.UnaryClientInterceptor
+	sci []grpc.StreamClientInterceptor
+}
+
+func (c *chain) UnaryServerInterceptor() grpc.UnaryServerInterceptor {
+	return grpc_middleware.ChainUnaryServer(c.usi...)
+}
+
+func (c *chain) StreamServerInterceptor() grpc.StreamServerInterceptor {
+	return grpc_middleware.ChainStreamServer(c.ssi...)
+}
+
+func (c *chain) UnaryClientInterceptor() grpc.UnaryClientInterceptor {
+	return grpc_middleware.ChainUnaryClient(c.uci...)
+}
+
+func (c *chain) StreamClientInterceptor() grpc.StreamClientInterceptor {
+	return grpc_middleware.ChainStreamClient(c.sci...)
+}