From 754a1bbe24d4d1f0ab1a0361b7fe27c1f3c8bab6 Mon Sep 17 00:00:00 2001 From: Daniel Nephin Date: Thu, 1 Oct 2020 14:41:47 -0400 Subject: [PATCH] Update proto for change to stream framing events --- proto/pbsubscribe/subscribe.pb.go | 160 ++++++++++++++++-------------- proto/pbsubscribe/subscribe.proto | 34 ++++--- 2 files changed, 106 insertions(+), 88 deletions(-) diff --git a/proto/pbsubscribe/subscribe.pb.go b/proto/pbsubscribe/subscribe.pb.go index 435307f98..35122711e 100644 --- a/proto/pbsubscribe/subscribe.pb.go +++ b/proto/pbsubscribe/subscribe.pb.go @@ -200,7 +200,7 @@ type Event struct { // // Types that are valid to be assigned to Payload: // *Event_EndOfSnapshot - // *Event_EndOfEmptySnapshot + // *Event_NewSnapshotToFollow // *Event_EventBatch // *Event_ServiceHealth Payload isEvent_Payload `protobuf_oneof:"Payload"` @@ -251,8 +251,8 @@ type isEvent_Payload interface { type Event_EndOfSnapshot struct { EndOfSnapshot bool `protobuf:"varint,5,opt,name=EndOfSnapshot,proto3,oneof"` } -type Event_EndOfEmptySnapshot struct { - EndOfEmptySnapshot bool `protobuf:"varint,6,opt,name=EndOfEmptySnapshot,proto3,oneof"` +type Event_NewSnapshotToFollow struct { + NewSnapshotToFollow bool `protobuf:"varint,6,opt,name=NewSnapshotToFollow,proto3,oneof"` } type Event_EventBatch struct { EventBatch *EventBatch `protobuf:"bytes,7,opt,name=EventBatch,proto3,oneof"` @@ -261,10 +261,10 @@ type Event_ServiceHealth struct { ServiceHealth *ServiceHealthUpdate `protobuf:"bytes,10,opt,name=ServiceHealth,proto3,oneof"` } -func (*Event_EndOfSnapshot) isEvent_Payload() {} -func (*Event_EndOfEmptySnapshot) isEvent_Payload() {} -func (*Event_EventBatch) isEvent_Payload() {} -func (*Event_ServiceHealth) isEvent_Payload() {} +func (*Event_EndOfSnapshot) isEvent_Payload() {} +func (*Event_NewSnapshotToFollow) isEvent_Payload() {} +func (*Event_EventBatch) isEvent_Payload() {} +func (*Event_ServiceHealth) isEvent_Payload() {} func (m *Event) GetPayload() isEvent_Payload { if m != nil { @@ -301,9 +301,9 @@ func (m *Event) GetEndOfSnapshot() bool { return false } -func (m *Event) GetEndOfEmptySnapshot() bool { - if x, ok := m.GetPayload().(*Event_EndOfEmptySnapshot); ok { - return x.EndOfEmptySnapshot +func (m *Event) GetNewSnapshotToFollow() bool { + if x, ok := m.GetPayload().(*Event_NewSnapshotToFollow); ok { + return x.NewSnapshotToFollow } return false } @@ -326,7 +326,7 @@ func (m *Event) GetServiceHealth() *ServiceHealthUpdate { func (*Event) XXX_OneofFuncs() (func(msg proto.Message, b *proto.Buffer) error, func(msg proto.Message, tag, wire int, b *proto.Buffer) (bool, error), func(msg proto.Message) (n int), []interface{}) { return _Event_OneofMarshaler, _Event_OneofUnmarshaler, _Event_OneofSizer, []interface{}{ (*Event_EndOfSnapshot)(nil), - (*Event_EndOfEmptySnapshot)(nil), + (*Event_NewSnapshotToFollow)(nil), (*Event_EventBatch)(nil), (*Event_ServiceHealth)(nil), } @@ -343,9 +343,9 @@ func _Event_OneofMarshaler(msg proto.Message, b *proto.Buffer) error { } _ = b.EncodeVarint(5<<3 | proto.WireVarint) _ = b.EncodeVarint(t) - case *Event_EndOfEmptySnapshot: + case *Event_NewSnapshotToFollow: t := uint64(0) - if x.EndOfEmptySnapshot { + if x.NewSnapshotToFollow { t = 1 } _ = b.EncodeVarint(6<<3 | proto.WireVarint) @@ -377,12 +377,12 @@ func _Event_OneofUnmarshaler(msg proto.Message, tag, wire int, b *proto.Buffer) x, err := b.DecodeVarint() m.Payload = &Event_EndOfSnapshot{x != 0} return true, err - case 6: // Payload.EndOfEmptySnapshot + case 6: // Payload.NewSnapshotToFollow if wire != proto.WireVarint { return true, proto.ErrInternalBadWireType } x, err := b.DecodeVarint() - m.Payload = &Event_EndOfEmptySnapshot{x != 0} + m.Payload = &Event_NewSnapshotToFollow{x != 0} return true, err case 7: // Payload.EventBatch if wire != proto.WireBytes { @@ -412,7 +412,7 @@ func _Event_OneofSizer(msg proto.Message) (n int) { case *Event_EndOfSnapshot: n += 1 // tag and wire n += 1 - case *Event_EndOfEmptySnapshot: + case *Event_NewSnapshotToFollow: n += 1 // tag and wire n += 1 case *Event_EventBatch: @@ -546,40 +546,40 @@ func init() { func init() { proto.RegisterFile("proto/pbsubscribe/subscribe.proto", fileDescriptor_ab3eb8c810e315fb) } var fileDescriptor_ab3eb8c810e315fb = []byte{ - 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0xff, 0x7d, 0xf7, 0xca, 0x01, 0xf6, 0x03, 0x00, 0x00, + // 526 bytes of a gzipped FileDescriptorProto + 0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xa4, 0x53, 0x5f, 0x6f, 0xd2, 0x50, + 0x14, 0xef, 0x85, 0x01, 0xe3, 0xe0, 0x96, 0x7a, 0x87, 0xb1, 0x61, 0x49, 0x83, 0xc4, 0x2c, 0x75, + 0x89, 0xd4, 0x60, 0xa2, 0x6f, 0x1a, 0x61, 0x9b, 0x18, 0x93, 0x61, 0xca, 0xf6, 0xa0, 0x6f, 0x97, + 0xf6, 0x48, 0x1b, 0xea, 0xbd, 0xb5, 0xbd, 0x0c, 0xf7, 0xee, 0x87, 0xd8, 0xb7, 0xf1, 0xd5, 0x47, + 0x3f, 0x82, 0xc1, 0x2f, 0x62, 0xb8, 0x94, 0xae, 0xc0, 0xde, 0xf6, 0xd6, 0xf3, 0xfb, 0x73, 0xcf, + 0x2f, 0xe7, 0xf4, 0xc0, 0x93, 0x28, 0x16, 0x52, 0xd8, 0xd1, 0x28, 0x99, 0x8e, 0x12, 0x37, 0x0e, + 0x46, 0x68, 0x67, 0x5f, 0x6d, 0xc5, 0xd1, 0x6a, 0x06, 0x34, 0x1a, 0x99, 0x1a, 0xe3, 0xab, 0xc0, + 0x45, 0x9b, 0x0b, 0x2f, 0x95, 0xb5, 0x6e, 0x08, 0xe8, 0xc3, 0x95, 0xd2, 0xc1, 0xef, 0x53, 0x4c, + 0x24, 0x3d, 0x82, 0xd2, 0x85, 0x88, 0x02, 0xd7, 0x20, 0x4d, 0x62, 0xed, 0x77, 0xf4, 0xf6, 0xed, + 0xe3, 0x0a, 0x77, 0x96, 0x34, 0xd5, 0xa1, 0xf8, 0x11, 0xaf, 0x8d, 0x42, 0x93, 0x58, 0x55, 0x67, + 0xf1, 0x49, 0xeb, 0x0b, 0xe7, 0x04, 0xb9, 0x51, 0x54, 0xd8, 0xb2, 0x58, 0xa0, 0x1f, 0xb8, 0x87, + 0x3f, 0x8c, 0x9d, 0x26, 0xb1, 0x76, 0x9c, 0x65, 0x41, 0x4d, 0x80, 0x13, 0x26, 0x99, 0x8b, 0x5c, + 0x62, 0x6c, 0x94, 0x94, 0x21, 0x87, 0xb4, 0x7e, 0x15, 0xa0, 0x74, 0x7a, 0x85, 0xfc, 0x9e, 0x79, + 0x96, 0x9d, 0x8b, 0xf9, 0xce, 0x47, 0xb0, 0x77, 0xca, 0xbd, 0xc1, 0xd7, 0x21, 0x67, 0x51, 0xe2, + 0x0b, 0xa9, 0x9a, 0xef, 0xf6, 0x35, 0x67, 0x1d, 0xa6, 0x1d, 0x38, 0x38, 0xc7, 0xd9, 0xaa, 0xbc, + 0x10, 0x67, 0x22, 0x0c, 0xc5, 0xcc, 0x28, 0xa7, 0xea, 0xbb, 0x48, 0xfa, 0x1a, 0x40, 0x85, 0xee, + 0x32, 0xe9, 0xfa, 0x46, 0xa5, 0x49, 0xac, 0x5a, 0xe7, 0x51, 0x2e, 0xf0, 0x2d, 0xd9, 0xd7, 0x9c, + 0x9c, 0x94, 0x9e, 0xc1, 0xde, 0x70, 0xb9, 0x9f, 0x3e, 0xb2, 0x50, 0xfa, 0x06, 0x28, 0xaf, 0x99, + 0xf3, 0xae, 0xf1, 0x97, 0x91, 0xc7, 0x24, 0x2e, 0x42, 0xaf, 0xc1, 0xdd, 0x2a, 0x54, 0x3e, 0xb1, + 0xeb, 0x50, 0x30, 0xaf, 0xf5, 0x2a, 0x9f, 0x85, 0x5a, 0x50, 0x56, 0x55, 0x62, 0x90, 0x66, 0xd1, + 0xaa, 0xad, 0x8d, 0x51, 0x11, 0x4e, 0xca, 0xb7, 0x7e, 0x12, 0x38, 0xb8, 0xa3, 0x17, 0x7d, 0x0a, + 0x85, 0x41, 0x94, 0x2e, 0xa1, 0x9e, 0x73, 0xf7, 0x98, 0x64, 0xa1, 0x18, 0x0f, 0x22, 0xa7, 0x30, + 0x88, 0xe8, 0x7b, 0xd0, 0x7b, 0x3e, 0xba, 0x93, 0xf4, 0x85, 0x73, 0xe1, 0xa1, 0x5a, 0x49, 0xad, + 0x73, 0xd8, 0xce, 0xfe, 0xc1, 0xf6, 0xa6, 0xc4, 0xd9, 0x32, 0x1d, 0xbf, 0x4b, 0xd7, 0x4e, 0x6b, + 0x50, 0xb9, 0xe4, 0x13, 0x2e, 0x66, 0x5c, 0xd7, 0xe8, 0xc3, 0x8d, 0x39, 0xe9, 0x84, 0x1a, 0x50, + 0x5f, 0x83, 0x7a, 0x82, 0x73, 0x74, 0xa5, 0x5e, 0x38, 0x7e, 0x06, 0xd5, 0x2c, 0x1c, 0x7d, 0x00, + 0xbb, 0x0e, 0x8e, 0x83, 0x44, 0x62, 0xac, 0x6b, 0x74, 0x1f, 0xe0, 0x04, 0xe3, 0x55, 0x4d, 0x3a, + 0x9f, 0xe1, 0xf1, 0x50, 0x32, 0x89, 0x3d, 0x9f, 0xf1, 0x31, 0xa6, 0x37, 0x11, 0xc9, 0x40, 0x70, + 0xfa, 0x06, 0xaa, 0xd9, 0x8d, 0xd0, 0xc3, 0xfc, 0x42, 0x36, 0x2e, 0xa7, 0xb1, 0x35, 0xd3, 0x96, + 0xf6, 0x82, 0x74, 0xdf, 0xfe, 0x9e, 0x9b, 0xe4, 0xcf, 0xdc, 0x24, 0x7f, 0xe7, 0x26, 0xb9, 0xf9, + 0x67, 0x6a, 0x5f, 0x9e, 0x8f, 0x03, 0xe9, 0x4f, 0x47, 0x6d, 0x57, 0x7c, 0xb3, 0x7d, 0x96, 0xf8, + 0x81, 0x2b, 0xe2, 0xc8, 0x76, 0x05, 0x4f, 0xa6, 0xa1, 0xbd, 0x75, 0xdc, 0xa3, 0xb2, 0x82, 0x5e, + 0xfe, 0x0f, 0x00, 0x00, 0xff, 0xff, 0x44, 0xbc, 0x0a, 0xfb, 0xf8, 0x03, 0x00, 0x00, } // Reference imports to suppress errors if they are not otherwise used. @@ -595,18 +595,24 @@ const _ = grpc.SupportPackageIsVersion4 // For semantics around ctx use and closing/ending streaming RPCs, please refer to https://godoc.org/google.golang.org/grpc#ClientConn.NewStream. type StateChangeSubscriptionClient interface { // Subscribe to a topic to receive events when there are changes to the topic. - // TODO: document how to handle framing events // + // If SubscribeRequest.Index is 0 the event stream will start with one or + // more snapshot events, followed by an EndOfSnapshot event. Subsequent + // events will be a live stream of events as they happen. // - // Subscribe may return an ABORTED status error to indicate the client must - // re-start the Subscribe call. + // If SubscribeRequest.Index is > 0 it is assumed the client already has a + // snapshot, and is trying to resume a stream that was disconnected. The + // client will either receive a NewSnapshotToFollow event, indicating the + // client view is stale and it must reset its view and prepare for a new + // snapshot. Or, if no NewSnapshotToFollow event is received, the client + // view is still fresh, and all events will be the live stream. + // + // Subscribe may return a gRPC status error with codes.ABORTED to indicate + // the client view is now stale due to a change on the server. The client + // must reset its view and issue a new Subscribe call to restart the stream. // This error is used when the server can no longer correctly maintain the - // stream, for example because the ACL permissions for the token changed - // and the server doesn't know which previously delivered events should - // now not be visible. Clients when receiving this must reset their - // local copy of the state to empty and start over from index 0 to get a - // valid snapshot again. Servers may also send this if their state store - // is restored from a snapshot. + // stream, for example because the ACL permissions for the token changed, or + // because the server state was restored from a snapshot. Subscribe(ctx context.Context, in *SubscribeRequest, opts ...grpc.CallOption) (StateChangeSubscription_SubscribeClient, error) } @@ -653,18 +659,24 @@ func (x *stateChangeSubscriptionSubscribeClient) Recv() (*Event, error) { // StateChangeSubscriptionServer is the server API for StateChangeSubscription service. type StateChangeSubscriptionServer interface { // Subscribe to a topic to receive events when there are changes to the topic. - // TODO: document how to handle framing events // + // If SubscribeRequest.Index is 0 the event stream will start with one or + // more snapshot events, followed by an EndOfSnapshot event. Subsequent + // events will be a live stream of events as they happen. // - // Subscribe may return an ABORTED status error to indicate the client must - // re-start the Subscribe call. + // If SubscribeRequest.Index is > 0 it is assumed the client already has a + // snapshot, and is trying to resume a stream that was disconnected. The + // client will either receive a NewSnapshotToFollow event, indicating the + // client view is stale and it must reset its view and prepare for a new + // snapshot. Or, if no NewSnapshotToFollow event is received, the client + // view is still fresh, and all events will be the live stream. + // + // Subscribe may return a gRPC status error with codes.ABORTED to indicate + // the client view is now stale due to a change on the server. The client + // must reset its view and issue a new Subscribe call to restart the stream. // This error is used when the server can no longer correctly maintain the - // stream, for example because the ACL permissions for the token changed - // and the server doesn't know which previously delivered events should - // now not be visible. Clients when receiving this must reset their - // local copy of the state to empty and start over from index 0 to get a - // valid snapshot again. Servers may also send this if their state store - // is restored from a snapshot. + // stream, for example because the ACL permissions for the token changed, or + // because the server state was restored from a snapshot. Subscribe(*SubscribeRequest, StateChangeSubscription_SubscribeServer) error } @@ -842,14 +854,14 @@ func (m *Event_EndOfSnapshot) MarshalToSizedBuffer(dAtA []byte) (int, error) { dAtA[i] = 0x28 return len(dAtA) - i, nil } -func (m *Event_EndOfEmptySnapshot) MarshalTo(dAtA []byte) (int, error) { +func (m *Event_NewSnapshotToFollow) MarshalTo(dAtA []byte) (int, error) { return m.MarshalToSizedBuffer(dAtA[:m.Size()]) } -func (m *Event_EndOfEmptySnapshot) MarshalToSizedBuffer(dAtA []byte) (int, error) { +func (m *Event_NewSnapshotToFollow) MarshalToSizedBuffer(dAtA []byte) (int, error) { i := len(dAtA) i-- - if m.EndOfEmptySnapshot { + if m.NewSnapshotToFollow { dAtA[i] = 1 } else { dAtA[i] = 0 @@ -1058,7 +1070,7 @@ func (m *Event_EndOfSnapshot) Size() (n int) { n += 2 return n } -func (m *Event_EndOfEmptySnapshot) Size() (n int) { +func (m *Event_NewSnapshotToFollow) Size() (n int) { if m == nil { return 0 } @@ -1444,7 +1456,7 @@ func (m *Event) Unmarshal(dAtA []byte) error { m.Payload = &Event_EndOfSnapshot{b} case 6: if wireType != 0 { - return fmt.Errorf("proto: wrong wireType = %d for field EndOfEmptySnapshot", wireType) + return fmt.Errorf("proto: wrong wireType = %d for field NewSnapshotToFollow", wireType) } var v int for shift := uint(0); ; shift += 7 { @@ -1462,7 +1474,7 @@ func (m *Event) Unmarshal(dAtA []byte) error { } } b := bool(v != 0) - m.Payload = &Event_EndOfEmptySnapshot{b} + m.Payload = &Event_NewSnapshotToFollow{b} case 7: if wireType != 2 { return fmt.Errorf("proto: wrong wireType = %d for field EventBatch", wireType) diff --git a/proto/pbsubscribe/subscribe.proto b/proto/pbsubscribe/subscribe.proto index 82e3a1d30..c0efab87c 100644 --- a/proto/pbsubscribe/subscribe.proto +++ b/proto/pbsubscribe/subscribe.proto @@ -13,18 +13,24 @@ import "proto/pbservice/node.proto"; // state change events. Events are streamed as they happen. service StateChangeSubscription { // Subscribe to a topic to receive events when there are changes to the topic. - // TODO: document how to handle framing events // + // If SubscribeRequest.Index is 0 the event stream will start with one or + // more snapshot events, followed by an EndOfSnapshot event. Subsequent + // events will be a live stream of events as they happen. // - // Subscribe may return an ABORTED status error to indicate the client must - // re-start the Subscribe call. + // If SubscribeRequest.Index is > 0 it is assumed the client already has a + // snapshot, and is trying to resume a stream that was disconnected. The + // client will either receive a NewSnapshotToFollow event, indicating the + // client view is stale and it must reset its view and prepare for a new + // snapshot. Or, if no NewSnapshotToFollow event is received, the client + // view is still fresh, and all events will be the live stream. + // + // Subscribe may return a gRPC status error with codes.ABORTED to indicate + // the client view is now stale due to a change on the server. The client + // must reset its view and issue a new Subscribe call to restart the stream. // This error is used when the server can no longer correctly maintain the - // stream, for example because the ACL permissions for the token changed - // and the server doesn't know which previously delivered events should - // now not be visible. Clients when receiving this must reset their - // local copy of the state to empty and start over from index 0 to get a - // valid snapshot again. Servers may also send this if their state store - // is restored from a snapshot. + // stream, for example because the ACL permissions for the token changed, or + // because the server state was restored from a snapshot. rpc Subscribe(SubscribeRequest) returns (stream Event) {} } @@ -92,11 +98,11 @@ message Event { // ended. Subsequent Events delivered will be mutations to that result. bool EndOfSnapshot = 5; - // EndOfEmptySnapshot indicates that the client is still up-to-date. - // The snapshot has ended, and was empty. The rest of the stream will be - // individual update events. It distinguishes between "up to date, no snapshot" - // and "snapshot contains zero events but you should reset any old state to be blank". - bool EndOfEmptySnapshot = 6; + // NewSnapshotToFollow indicates that the client view is stale. The client + // must reset its view before handing any more events. Subsequent events + // in the stream will be for a new snapshot until an EndOfSnapshot event + // is received. + bool NewSnapshotToFollow = 6; // EventBatch is a set of events. This is typically used as the payload // type where multiple events are emitted in a single topic and raft