fix: map HTTP response status code to equivalent GRPC Status code

sdk/instrumentation/google.golang.org/grpc/server.go

@@ -11,7 +11,6 @@ import (
 	internalconfig "github.com/hypertrace/goagent/sdk/internal/config"
 	"github.com/hypertrace/goagent/sdk/internal/container"
 	"google.golang.org/grpc"
-	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/peer"
 	"google.golang.org/grpc/stats"
@@ -106,7 +105,7 @@ func wrapHandler(
 				}
 				filterResult := filter.EvaluateBody(span, processingBody, md)
 				if filterResult.Block {
-					return nil, status.Error(codes.Code(filterResult.ResponseStatusCode), StatusText(int(filterResult.ResponseStatusCode)))
+					return nil, status.Error(StatusCode(int(filterResult.ResponseStatusCode)), StatusText(int(filterResult.ResponseStatusCode)))
 				}
 			}
 		}
@@ -118,7 +117,7 @@ func wrapHandler(
 				// TODO: decide what should be passed as URL in GRPC
 				filterResult := filter.EvaluateURLAndHeaders(span, "", md)
 				if filterResult.Block {
-					return nil, status.Error(codes.Code(filterResult.ResponseStatusCode), StatusText(int(filterResult.ResponseStatusCode)))
+					return nil, status.Error(StatusCode(int(filterResult.ResponseStatusCode)), StatusText(int(filterResult.ResponseStatusCode)))
 				}
 			}
 		}

sdk/instrumentation/google.golang.org/grpc/server_test.go

@@ -104,14 +104,17 @@ func TestServerInterceptorFilter(t *testing.T) {
 
 	tCases := map[string]struct {
 		expectedFilterResult bool
+		expectedStatusCode   codes.Code
 		multiFilter          *filter.MultiFilter
 	}{
 		"no filter": {
 			expectedFilterResult: false,
+			expectedStatusCode:   codes.OK,
 			multiFilter:          filter.NewMultiFilter(),
 		},
 		"headers filter": {
 			expectedFilterResult: true,
+			expectedStatusCode:   codes.PermissionDenied,
 			multiFilter: filter.NewMultiFilter(mock.Filter{
 				URLAndHeadersEvaluator: func(span sdk.Span, url string, headers map[string][]string) result.FilterResult {
 					assert.Equal(t, []string{"test_value"}, headers["test_key"])
@@ -121,13 +124,24 @@ func TestServerInterceptorFilter(t *testing.T) {
 		},
 		"body filter": {
 			expectedFilterResult: true,
+			expectedStatusCode:   codes.PermissionDenied,
 			multiFilter: filter.NewMultiFilter(mock.Filter{
 				BodyEvaluator: func(span sdk.Span, body []byte, headers map[string][]string) result.FilterResult {
 					assert.Equal(t, "{\"name\":\"Pupo\"}", string(body))
 					return result.FilterResult{Block: true, ResponseStatusCode: 403}
 				},
 			}),
 		},
+		"body filter return 412 Precondition failed": {
+			expectedFilterResult: true,
+			expectedStatusCode:   codes.FailedPrecondition,
+			multiFilter: filter.NewMultiFilter(mock.Filter{
+				BodyEvaluator: func(span sdk.Span, body []byte, headers map[string][]string) result.FilterResult {
+					assert.Equal(t, "{\"name\":\"Pupo\"}", string(body))
+					return result.FilterResult{Block: true, ResponseStatusCode: 412}
+				},
+			}),
+		},
 	}
 
 	spans := []*mock.Span{}
@@ -167,7 +181,7 @@ func TestServerInterceptorFilter(t *testing.T) {
 				Name: "Pupo",
 			})
 			if tCase.expectedFilterResult {
-				assert.Equal(t, codes.Code(403), status.Code(err))
+				assert.Equal(t, tCase.expectedStatusCode, status.Code(err))
 			} else {
 				assert.Nil(t, err)
 			}

sdk/instrumentation/google.golang.org/grpc/status_text.go → sdk/instrumentation/google.golang.org/grpc/status.go

@@ -1,5 +1,9 @@
 package grpc
 
+import (
+	"google.golang.org/grpc/codes"
+)
+
 func StatusText(code int) string {
 	switch code {
 	case 400:
@@ -64,3 +68,31 @@ func StatusText(code int) string {
 		return "Request Error"
 	}
 }
+
+// StatusCode does a best effort mapping from HTTP Request Status code to GRPC Code.
+func StatusCode(code int) codes.Code {
+	switch code {
+	case 401:
+		return codes.Unauthenticated
+	case 403:
+		return codes.PermissionDenied
+	case 404:
+		return codes.NotFound
+	case 407:
+		// "Proxy Authentication Required"
+		return codes.Unauthenticated
+	case 408:
+		// Request Timeout
+		return codes.DeadlineExceeded
+	case 412:
+		// "Precondition Failed"
+		return codes.FailedPrecondition
+	case 413, // "Request Entity Too Large"
+		414, // "Request URI Too Long"
+		429, // "Too Many Requests"
+		431: // "Request Header Fields Too Large"
+		return codes.ResourceExhausted
+	default:
+		return codes.Unknown
+	}
+}

sdk/instrumentation/google.golang.org/grpc/status_test.go

@@ -0,0 +1,23 @@
+package grpc
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"google.golang.org/grpc/codes"
+)
+
+func TestStatusCode(t *testing.T) {
+	assert.Equal(t, codes.Unauthenticated, StatusCode(401))
+	assert.Equal(t, codes.PermissionDenied, StatusCode(403))
+	assert.Equal(t, codes.NotFound, StatusCode(404))
+	assert.Equal(t, codes.Unauthenticated, StatusCode(407))
+	assert.Equal(t, codes.DeadlineExceeded, StatusCode(408))
+	assert.Equal(t, codes.FailedPrecondition, StatusCode(412))
+	assert.Equal(t, codes.ResourceExhausted, StatusCode(413))
+	assert.Equal(t, codes.ResourceExhausted, StatusCode(414))
+	assert.Equal(t, codes.ResourceExhausted, StatusCode(429))
+	assert.Equal(t, codes.ResourceExhausted, StatusCode(431))
+	assert.Equal(t, codes.Unknown, StatusCode(400))
+	assert.Equal(t, codes.Unknown, StatusCode(500))
+}