filter out context errors

Author: amacaskill

pkg/gce-pd-csi-driver/utils.go

@@ -20,6 +20,7 @@ import (
 	"errors"
 	"fmt"
 	"net/http"
+	"strings"
 
 	"context"
 
@@ -219,14 +220,21 @@ func containsZone(zones []string, zone string) bool {
 }
 
 // CodeForError returns a pointer to the grpc error code that maps to the http
-// error code for the passed in user googleapi error. Returns codes.Internal if
-// the given error is not a googleapi error caused by the user. The following
-// http error codes are considered user errors:
+// error code for the passed in user googleapi error or context error. Returns
+// codes.Internal if the given error is not a googleapi error caused by the user.
+// The following http error codes are considered user errors:
 // (1) http 400 Bad Request, returns grpc InvalidArgument,
 // (2) http 403 Forbidden, returns grpc PermissionDenied,
 // (3) http 404 Not Found, returns grpc NotFound
 // (4) http 429 Too Many Requests, returns grpc ResourceExhausted
+// The following errors are considered context errors:
+// (1) "context deadline exceeded", returns grpc DeadlineExceeded,
+// (2) "context canceled", returns grpc Canceled
 func CodeForError(err error) *codes.Code {
+	if code := isContextError(err); code != nil {
+		return code
+	}
+
 	internalErrorCode := codes.Internal
 	// Upwrap the error
 	var apiErr *googleapi.Error
@@ -243,9 +251,32 @@ func CodeForError(err error) *codes.Code {
 	if code, ok := userErrors[apiErr.Code]; ok {
 		return &code
 	}
+
 	return &internalErrorCode
 }
 
+// isContextError returns a pointer to the grpc error code DeadlineExceeded
+// if the passed in error contains the "context deadline exceeded" string and returns
+// the grpc error code Canceled if the error contains the "context canceled" string.
+func isContextError(err error) *codes.Code {
+	if err == nil {
+		return nil
+	}
+
+	errStr := err.Error()
+	if strings.Contains(errStr, context.DeadlineExceeded.Error()) {
+		return errCodePtr(codes.DeadlineExceeded)
+	}
+	if strings.Contains(errStr, context.Canceled.Error()) {
+		return errCodePtr(codes.Canceled)
+	}
+	return nil
+}
+
+func errCodePtr(code codes.Code) *codes.Code {
+	return &code
+}
+
 func LoggedError(msg string, err error) error {
 	klog.Errorf(msg+"%v", err.Error())
 	return status.Errorf(*CodeForError(err), msg+"%v", err.Error())

pkg/gce-pd-csi-driver/utils_test.go

@@ -18,7 +18,9 @@ limitations under the License.
 package gceGCEDriver
 
 import (
+	"context"
 	"errors"
+	"fmt"
 	"net/http"
 	"testing"
 
@@ -319,6 +321,16 @@ func TestCodeForError(t *testing.T) {
 			inputErr: &googleapi.Error{Code: http.StatusInternalServerError, Message: "Internal error"},
 			expCode:  &internalErrorCode,
 		},
+		{
+			name:     "context canceled error",
+			inputErr: context.Canceled,
+			expCode:  errCodePtr(codes.Canceled),
+		},
+		{
+			name:     "context deadline exceeded error",
+			inputErr: context.DeadlineExceeded,
+			expCode:  errCodePtr(codes.DeadlineExceeded),
+		},
 	}
 
 	for _, tc := range testCases {
@@ -329,3 +341,52 @@ func TestCodeForError(t *testing.T) {
 		}
 	}
 }
+
+func TestIsContextError(t *testing.T) {
+	cases := []struct {
+		name            string
+		err             error
+		expectedErrCode *codes.Code
+	}{
+		{
+			name:            "deadline exceeded error",
+			err:             context.DeadlineExceeded,
+			expectedErrCode: errCodePtr(codes.DeadlineExceeded),
+		},
+		{
+			name:            "contains 'context deadline exceeded'",
+			err:             fmt.Errorf("got error: %w", context.DeadlineExceeded),
+			expectedErrCode: errCodePtr(codes.DeadlineExceeded),
+		},
+		{
+			name:            "context canceled error",
+			err:             context.Canceled,
+			expectedErrCode: errCodePtr(codes.Canceled),
+		},
+		{
+			name:            "contains 'context canceled'",
+			err:             fmt.Errorf("got error: %w", context.Canceled),
+			expectedErrCode: errCodePtr(codes.Canceled),
+		},
+		{
+			name:            "does not contain 'context canceled' or 'context deadline exceeded'",
+			err:             fmt.Errorf("unknown error"),
+			expectedErrCode: nil,
+		},
+		{
+			name:            "nil error",
+			err:             nil,
+			expectedErrCode: nil,
+		},
+	}
+
+	for _, test := range cases {
+		errCode := isContextError(test.err)
+		if (test.expectedErrCode == nil) != (errCode == nil) {
+			t.Errorf("test %v failed: got %v, expected %v", test.name, errCode, test.expectedErrCode)
+		}
+		if test.expectedErrCode != nil && *errCode != *test.expectedErrCode {
+			t.Errorf("test %v failed: got %v, expected %v", test.name, errCode, test.expectedErrCode)
+		}
+	}
+}