grpc: Return external dependencies to client

go.mod

@@ -20,7 +20,7 @@ require (
 	github.com/google/uuid v1.6.0
 	github.com/gorilla/mux v1.8.1
 	github.com/grpc-ecosystem/go-grpc-middleware/providers/prometheus v1.0.1
-	github.com/grpc-ecosystem/go-grpc-middleware/v2 v2.2.0
+	github.com/grpc-ecosystem/go-grpc-middleware/v2 v2.3.0
 	github.com/jpillora/backoff v1.0.0
 	github.com/mattn/go-isatty v0.0.20
 	github.com/minio/minio-go/v7 v7.0.7
@@ -38,9 +38,9 @@ require (
 	github.com/uptrace/bun/dialect/pgdialect v1.2.9
 	github.com/uptrace/bun/driver/pgdriver v1.2.9
 	github.com/zenazn/goji v1.0.1
-	golang.org/x/text v0.21.0
+	golang.org/x/text v0.22.0
 	google.golang.org/grpc v1.67.1
-	google.golang.org/protobuf v1.34.2
+	google.golang.org/protobuf v1.36.4
 )
 
 require (
@@ -74,9 +74,9 @@ require (
 	github.com/yuin/gopher-lua v1.1.0 // indirect
 	go.opentelemetry.io/otel v1.34.0 // indirect
 	go.opentelemetry.io/otel/trace v1.34.0 // indirect
-	golang.org/x/crypto v0.32.0 // indirect
-	golang.org/x/net v0.28.0 // indirect
-	golang.org/x/sys v0.29.0 // indirect
+	golang.org/x/crypto v0.33.0 // indirect
+	golang.org/x/net v0.35.0 // indirect
+	golang.org/x/sys v0.30.0 // indirect
 	golang.org/x/xerrors v0.0.0-20220907171357-04be3eba64a2 // indirect
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20240903143218-8af14fe29dc1 // indirect
 	gopkg.in/ini.v1 v1.67.0 // indirect

go.sum

@@ -1,5 +1,4 @@
 bou.ke/monkey v1.0.1/go.mod h1:FgHuK96Rv2Nlf+0u1OOVDpCMdsWyOFmeeketDHE7LIg=
-cloud.google.com/go/compute v1.23.4 h1:EBT9Nw4q3zyE7G45Wvv3MzolIrCJEuHys5muLY0wvAw=
 cloud.google.com/go/compute/metadata v0.5.0 h1:Zr0eK8JbFv6+Wi4ilXAR8FJ3wyNdpxHKJNPos6LTZOY=
 cloud.google.com/go/compute/metadata v0.5.0/go.mod h1:aHnloV2TPI38yx4s9+wAZhHykWvVCfu7hQbF+9CWoiY=
 github.com/PuerkitoBio/rehttp v1.4.0 h1:rIN7A2s+O9fmHUM1vUcInvlHj9Ysql4hE+Y0wcl/xk8=
@@ -79,8 +78,8 @@ github.com/gorilla/mux v1.8.1 h1:TuBL49tXwgrFYWhqrNgrUNEY92u81SPhu7sTdzQEiWY=
 github.com/gorilla/mux v1.8.1/go.mod h1:AKf9I4AEqPTmMytcMc0KkNouC66V3BtZ4qD5fmWSiMQ=
 github.com/grpc-ecosystem/go-grpc-middleware/providers/prometheus v1.0.1 h1:qnpSQwGEnkcRpTqNOIR6bJbR0gAorgP9CSALpRcKoAA=
 github.com/grpc-ecosystem/go-grpc-middleware/providers/prometheus v1.0.1/go.mod h1:lXGCsh6c22WGtjr+qGHj1otzZpV/1kwTMAqkwZsnWRU=
-github.com/grpc-ecosystem/go-grpc-middleware/v2 v2.2.0 h1:kQ0NI7W1B3HwiN5gAYtY+XFItDPbLBwYRxAqbFTyDes=
-github.com/grpc-ecosystem/go-grpc-middleware/v2 v2.2.0/go.mod h1:zrT2dxOAjNFPRGjTUe2Xmb4q4YdUwVvQFV6xiCSf+z0=
+github.com/grpc-ecosystem/go-grpc-middleware/v2 v2.3.0 h1:FbSCl+KggFl+Ocym490i/EyXF4lPgLoUtcSWquBM0Rs=
+github.com/grpc-ecosystem/go-grpc-middleware/v2 v2.3.0/go.mod h1:qOchhhIlmRcqk/O9uCo/puJlyo07YINaIqdZfZG3Jkc=
 github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2s0bqwp9tc8=
 github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
 github.com/jinzhu/inflection v1.0.0 h1:K317FqzuhWc8YvSVlFMCCUb36O/S9MCKRDI7QkRKD/E=
@@ -209,19 +208,19 @@ golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACk
 golang.org/x/crypto v0.0.0-20190513172903-22d7a77e9e5f/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/crypto v0.0.0-20200709230013-948cd5f35899/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
-golang.org/x/crypto v0.32.0 h1:euUpcYgM8WcP71gNpTqQCn6rC2t6ULUPiOzfWaXVVfc=
-golang.org/x/crypto v0.32.0/go.mod h1:ZnnJkOaASj8g0AjIduWNlq2NRxL0PlBrbKVyZ6V/Ugc=
+golang.org/x/crypto v0.33.0 h1:IOBPskki6Lysi0lo9qQvbxiQ+FvsCC/YWOecCHAixus=
+golang.org/x/crypto v0.33.0/go.mod h1:bVdXmD7IV/4GdElGPozy6U7lWdRXA4qyRVGJV57uQ5M=
 golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20200707034311-ab3426394381/go.mod h1:/O7V0waA8r7cgGh81Ro3o1hOxt32SMVPicZroKQ2sZA=
 golang.org/x/net v0.0.0-20201110031124-69a78807bb2b/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
 golang.org/x/net v0.0.0-20210510120150-4163338589ed/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
-golang.org/x/net v0.28.0 h1:a9JDOJc5GMUJ0+UDqmLT86WiEy7iWyIhz8gz8E4e5hE=
-golang.org/x/net v0.28.0/go.mod h1:yqtgsTWOOnlGLG9GFRrK3++bGOUEkNBoHZc8MEDWPNg=
+golang.org/x/net v0.35.0 h1:T5GQRQb2y08kTAByq9L4/bz8cipCdA8FbRTXewonqY8=
+golang.org/x/net v0.35.0/go.mod h1:EglIi67kWsHKlRzzVMUD93VMSWGFOMSZgxFjparz1Qk=
 golang.org/x/oauth2 v0.22.0 h1:BzDx2FehcG7jJwgWLELCdmLuxk2i+x9UDpSiss2u0ZA=
 golang.org/x/oauth2 v0.22.0/go.mod h1:XYTD2NtWslqkgxebSiOHnXEap4TF09sJSc7H1sXbhtI=
-golang.org/x/sync v0.10.0 h1:3NQrjDixjgGwUOCaF8w2+VYHv0Ve/vGYSbdkTa98gmQ=
-golang.org/x/sync v0.10.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
+golang.org/x/sync v0.11.0 h1:GGz8+XQP4FvTTrjZPzNKTMFtSXH80RAzG+5ghFPgK9w=
+golang.org/x/sync v0.11.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
 golang.org/x/sys v0.0.0-20190204203706-41f3e6584952/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190222072716-a9d3bda3a223/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
@@ -235,14 +234,14 @@ golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.12.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.29.0 h1:TPYlXGxvx1MGTn2GiZDhnjPA9wZzZeGKHHmKhHYvgaU=
-golang.org/x/sys v0.29.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/sys v0.30.0 h1:QjkSwP/36a20jFYWkSue1YwXzLmsV5Gfq7Eiy72C1uc=
+golang.org/x/sys v0.30.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
-golang.org/x/text v0.21.0 h1:zyQAAkrwaneQ066sspRyJaG9VNi/YJ1NfzcGB3hZ/qo=
-golang.org/x/text v0.21.0/go.mod h1:4IBbMaMmOPCJ8SecivzSH54+73PCFmPWxNTLm+vZkEQ=
+golang.org/x/text v0.22.0 h1:bofq7m3/HAFvbF51jz3Q9wLg3jkvSPuiZu/pD1XwgtM=
+golang.org/x/text v0.22.0/go.mod h1:YRoo4H8PVmsu+E3Ou7cqLVH8oXWIHVoX0jqUWALQhfY=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20190328211700-ab21143f2384/go.mod h1:LCzVGOaR6xXOjkQ3onu1FJEFr0SW1gC7cKk1uF8kGRs=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
@@ -254,8 +253,8 @@ google.golang.org/genproto/googleapis/rpc v0.0.0-20240903143218-8af14fe29dc1 h1:
 google.golang.org/genproto/googleapis/rpc v0.0.0-20240903143218-8af14fe29dc1/go.mod h1:UqMtugtsSgubUsoxbuAoiCXvqvErP7Gf0so0mK9tHxU=
 google.golang.org/grpc v1.67.1 h1:zWnc1Vrcno+lHZCOofnIMvycFcc0QRGIzm9dhnDX68E=
 google.golang.org/grpc v1.67.1/go.mod h1:1gLDyUQU7CTLJI90u3nXZ9ekeghjeM7pTDZlqFNg2AA=
-google.golang.org/protobuf v1.34.2 h1:6xV6lTsCfpGD21XK49h7MhtcApnLqkfYgPcdHftf6hg=
-google.golang.org/protobuf v1.34.2/go.mod h1:qYOHts0dSfpeUzUFpOMr/WGzszTmLH+DiWniOlNbLDw=
+google.golang.org/protobuf v1.36.4 h1:6A3ZDJHn/eNqc1i+IdefRzy/9PokBTPvcqMySR7NNIM=
+google.golang.org/protobuf v1.36.4/go.mod h1:9fA7Ob0pmnwhb644+1+CVWFRbNajQ6iRojtC/QF5bRE=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=

grpc/client.go

@@ -36,6 +36,7 @@ func NewClient(addr string) (*grpc.ClientConn, error) {
 
 	opts := []grpc_retry.CallOption{
 		grpc_retry.WithBackoff(grpc_retry.BackoffLinear(100 * time.Millisecond)),
+		grpc_retry.WithMax(10),
 	}
 
 	conn, err := grpc.NewClient(addr,

grpc/middleware.go

@@ -7,6 +7,7 @@ import (
 	"encoding/gob"
 	"strings"
 
+	"github.com/pace/bricks/http/middleware"
 	"github.com/pace/bricks/pkg/tracking/utm"
 	"google.golang.org/grpc/metadata"
 )
@@ -36,3 +37,22 @@ func EncodeContextWithUTMData(parentCtx context.Context) context.Context {
 	}
 	return metadata.AppendToOutgoingContext(parentCtx, utmMetadataKey, w.String())
 }
+
+// AddExternalDependencyMetadataToContext adds external dependencies to the context if they are present in the metadata.
+func AddExternalDependencyMetadataToContext(ctx context.Context, md metadata.MD) context.Context {
+	// If there are no external dependencies in the metadata, we can return the context as is.
+	externalDependencies := md.Get(MetadataKeyExternalDependencies)
+	if len(externalDependencies) == 0 {
+		return ctx
+	}
+
+	// If there are external dependencies in the metadata, we need to parse them and add them to the context.
+	edc := middleware.ExternalDependencyContextFromContext(ctx)
+	if edc == nil {
+		edc = &middleware.ExternalDependencyContext{}
+	}
+
+	edc.Parse(externalDependencies[0])
+
+	return middleware.ContextWithExternalDependency(ctx, edc)
+}

grpc/middleware_test.go

@@ -6,6 +6,7 @@ import (
 	"context"
 	"testing"
 
+	"github.com/pace/bricks/http/middleware"
 	"github.com/pace/bricks/pkg/tracking/utm"
 	"github.com/stretchr/testify/require"
 	"google.golang.org/grpc/metadata"
@@ -31,3 +32,29 @@ func TestEncodeContextWithUTMData(t *testing.T) {
 	require.True(t, exists)
 	require.Equal(t, data, utmData)
 }
+
+func TestAddExternalDependencyMetadataToContext(t *testing.T) {
+	md := metadata.New(map[string]string{
+		MetadataKeyExternalDependencies: "dep1:1,dep2:2,dep3:3",
+	})
+	ctx := context.Background()
+	ctx = AddExternalDependencyMetadataToContext(ctx, md)
+	edc := middleware.ExternalDependencyContextFromContext(ctx)
+	require.NotNil(t, edc)
+	require.Equal(t, "dep1:1,dep2:2,dep3:3", edc.String())
+
+	ctx = AddExternalDependencyMetadataToContext(ctx, metadata.New(map[string]string{
+		MetadataKeyExternalDependencies: "dep4:4,dep5:5,dep6:6",
+	}))
+	edc = middleware.ExternalDependencyContextFromContext(ctx)
+	require.NotNil(t, edc)
+	require.Equal(t, "dep1:1,dep2:2,dep3:3,dep4:4,dep5:5,dep6:6", edc.String())
+}
+
+func TestAddExternalDependencyMetadataToContext_NoDependencies(t *testing.T) {
+	md := metadata.New(map[string]string{})
+	ctx := context.Background()
+	ctx = AddExternalDependencyMetadataToContext(ctx, md)
+	edc := middleware.ExternalDependencyContextFromContext(ctx)
+	require.Nil(t, edc)
+}

grpc/server.go

@@ -88,6 +88,10 @@ func Server(ab AuthBackend, logger grpc_logging.Logger) *grpc.Server {
 				start := time.Now()
 				err := handler(srv, wrappedStream)
 
+				if err := addExternalDependencyToTrailer(ctx); err != nil {
+					log.Ctx(ctx).Warn().Err(err).Msg("unable to add external dependencies to trailer")
+				}
+
 				log.Ctx(ctx).Info().Str("method", info.FullMethod).
 					Dur("duration", time.Since(start)).
 					Str("type", "stream").
@@ -120,6 +124,10 @@ func Server(ab AuthBackend, logger grpc_logging.Logger) *grpc.Server {
 				start := time.Now()
 				resp, err = handler(ctx, req)
 
+				if err := addExternalDependencyToTrailer(ctx); err != nil {
+					log.Ctx(ctx).Warn().Err(err).Msg("unable to add external dependencies to trailer")
+				}
+
 				log.Ctx(ctx).Info().Str("method", info.FullMethod).
 					Dur("duration", time.Since(start)).
 					Str("type", "unary").
@@ -143,6 +151,19 @@ func Server(ab AuthBackend, logger grpc_logging.Logger) *grpc.Server {
 	return myServer
 }
 
+// addExternalDependencyToTrailer adds the external dependencies to the grpc trailer.
+// This is used to track external dependencies which are updated during the request lifecycle.
+func addExternalDependencyToTrailer(ctx context.Context) error {
+	edc := middleware.ExternalDependencyContextFromContext(ctx)
+	if edc == nil {
+		return nil
+	}
+
+	md := metadata.Pairs(MetadataKeyExternalDependencies, edc.String())
+
+	return grpc.SetTrailer(ctx, md)
+}
+
 func prepareContext(ctx context.Context) (context.Context, metadata.MD) {
 	md, _ := metadata.FromIncomingContext(ctx)
 	logger := zlog.With().Logger()