Merge pull request #17 from izumin5210/izumin5210/stream

Add error handler for stream servers

Author: izumin5210

stream_server_error_handlers.go

@@ -0,0 +1,37 @@
+package grpcerrors
+
+import (
+	"github.com/creasty/apperrors"
+	"golang.org/x/net/context"
+	"google.golang.org/grpc"
+)
+
+// StreamServerAppErrorHandlerFunc is a function that called by stream server interceptors when specified application erorrs are detected.
+type StreamServerAppErrorHandlerFunc func(context.Context, interface{}, interface{}, *grpc.StreamServerInfo, *apperrors.Error) error
+
+type streamServerAppErrorHandler struct {
+	f StreamServerAppErrorHandlerFunc
+}
+
+func (h *streamServerAppErrorHandler) HandleStreamServerError(c context.Context, req interface{}, resp interface{}, info *grpc.StreamServerInfo, err error) error {
+	appErr := apperrors.Unwrap(err)
+	if appErr != nil {
+		return h.f(c, req, resp, info, appErr)
+	}
+	return err
+}
+
+// WithStreamServerAppErrorHandler returns a new error handler for stream servers for handling errors wrapped with apperrors.
+func WithStreamServerAppErrorHandler(f StreamServerAppErrorHandlerFunc) StreamServerErrorHandler {
+	return &streamServerAppErrorHandler{f: f}
+}
+
+// WithStreamServerReportableErrorHandler returns a new error handler for stream servers for handling errors annotated with the reportability.
+func WithStreamServerReportableErrorHandler(f StreamServerAppErrorHandlerFunc) StreamServerErrorHandler {
+	return WithStreamServerAppErrorHandler(func(c context.Context, req interface{}, resp interface{}, info *grpc.StreamServerInfo, err *apperrors.Error) error {
+		if err.Report {
+			return f(c, req, resp, info, err)
+		}
+		return err
+	})
+}