khenaidoo | 2672188 | 2021-08-11 17:42:52 -0400 | [diff] [blame] | 1 | // Copyright 2016 The etcd Authors |
| 2 | // |
| 3 | // Licensed under the Apache License, Version 2.0 (the "License"); |
| 4 | // you may not use this file except in compliance with the License. |
| 5 | // You may obtain a copy of the License at |
| 6 | // |
| 7 | // http://www.apache.org/licenses/LICENSE-2.0 |
| 8 | // |
| 9 | // Unless required by applicable law or agreed to in writing, software |
| 10 | // distributed under the License is distributed on an "AS IS" BASIS, |
| 11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 12 | // See the License for the specific language governing permissions and |
| 13 | // limitations under the License. |
| 14 | |
| 15 | package v3rpc |
| 16 | |
| 17 | import ( |
| 18 | "context" |
| 19 | "io" |
| 20 | |
| 21 | "github.com/coreos/etcd/etcdserver" |
| 22 | "github.com/coreos/etcd/etcdserver/api/v3rpc/rpctypes" |
| 23 | pb "github.com/coreos/etcd/etcdserver/etcdserverpb" |
| 24 | "github.com/coreos/etcd/lease" |
| 25 | ) |
| 26 | |
| 27 | type LeaseServer struct { |
| 28 | hdr header |
| 29 | le etcdserver.Lessor |
| 30 | } |
| 31 | |
| 32 | func NewLeaseServer(s *etcdserver.EtcdServer) pb.LeaseServer { |
| 33 | return &LeaseServer{le: s, hdr: newHeader(s)} |
| 34 | } |
| 35 | |
| 36 | func (ls *LeaseServer) LeaseGrant(ctx context.Context, cr *pb.LeaseGrantRequest) (*pb.LeaseGrantResponse, error) { |
| 37 | resp, err := ls.le.LeaseGrant(ctx, cr) |
| 38 | |
| 39 | if err != nil { |
| 40 | return nil, togRPCError(err) |
| 41 | } |
| 42 | ls.hdr.fill(resp.Header) |
| 43 | return resp, nil |
| 44 | } |
| 45 | |
| 46 | func (ls *LeaseServer) LeaseRevoke(ctx context.Context, rr *pb.LeaseRevokeRequest) (*pb.LeaseRevokeResponse, error) { |
| 47 | resp, err := ls.le.LeaseRevoke(ctx, rr) |
| 48 | if err != nil { |
| 49 | return nil, togRPCError(err) |
| 50 | } |
| 51 | ls.hdr.fill(resp.Header) |
| 52 | return resp, nil |
| 53 | } |
| 54 | |
| 55 | func (ls *LeaseServer) LeaseTimeToLive(ctx context.Context, rr *pb.LeaseTimeToLiveRequest) (*pb.LeaseTimeToLiveResponse, error) { |
| 56 | resp, err := ls.le.LeaseTimeToLive(ctx, rr) |
| 57 | if err != nil && err != lease.ErrLeaseNotFound { |
| 58 | return nil, togRPCError(err) |
| 59 | } |
| 60 | if err == lease.ErrLeaseNotFound { |
| 61 | resp = &pb.LeaseTimeToLiveResponse{ |
| 62 | Header: &pb.ResponseHeader{}, |
| 63 | ID: rr.ID, |
| 64 | TTL: -1, |
| 65 | } |
| 66 | } |
| 67 | ls.hdr.fill(resp.Header) |
| 68 | return resp, nil |
| 69 | } |
| 70 | |
| 71 | func (ls *LeaseServer) LeaseLeases(ctx context.Context, rr *pb.LeaseLeasesRequest) (*pb.LeaseLeasesResponse, error) { |
| 72 | resp, err := ls.le.LeaseLeases(ctx, rr) |
| 73 | if err != nil && err != lease.ErrLeaseNotFound { |
| 74 | return nil, togRPCError(err) |
| 75 | } |
| 76 | if err == lease.ErrLeaseNotFound { |
| 77 | resp = &pb.LeaseLeasesResponse{ |
| 78 | Header: &pb.ResponseHeader{}, |
| 79 | Leases: []*pb.LeaseStatus{}, |
| 80 | } |
| 81 | } |
| 82 | ls.hdr.fill(resp.Header) |
| 83 | return resp, nil |
| 84 | } |
| 85 | |
| 86 | func (ls *LeaseServer) LeaseKeepAlive(stream pb.Lease_LeaseKeepAliveServer) (err error) { |
| 87 | errc := make(chan error, 1) |
| 88 | go func() { |
| 89 | errc <- ls.leaseKeepAlive(stream) |
| 90 | }() |
| 91 | select { |
| 92 | case err = <-errc: |
| 93 | case <-stream.Context().Done(): |
| 94 | // the only server-side cancellation is noleader for now. |
| 95 | err = stream.Context().Err() |
| 96 | if err == context.Canceled { |
| 97 | err = rpctypes.ErrGRPCNoLeader |
| 98 | } |
| 99 | } |
| 100 | return err |
| 101 | } |
| 102 | |
| 103 | func (ls *LeaseServer) leaseKeepAlive(stream pb.Lease_LeaseKeepAliveServer) error { |
| 104 | for { |
| 105 | req, err := stream.Recv() |
| 106 | if err == io.EOF { |
| 107 | return nil |
| 108 | } |
| 109 | if err != nil { |
| 110 | if isClientCtxErr(stream.Context().Err(), err) { |
| 111 | plog.Debugf("failed to receive lease keepalive request from gRPC stream (%q)", err.Error()) |
| 112 | } else { |
| 113 | plog.Warningf("failed to receive lease keepalive request from gRPC stream (%q)", err.Error()) |
| 114 | } |
| 115 | return err |
| 116 | } |
| 117 | |
| 118 | // Create header before we sent out the renew request. |
| 119 | // This can make sure that the revision is strictly smaller or equal to |
| 120 | // when the keepalive happened at the local server (when the local server is the leader) |
| 121 | // or remote leader. |
| 122 | // Without this, a lease might be revoked at rev 3 but client can see the keepalive succeeded |
| 123 | // at rev 4. |
| 124 | resp := &pb.LeaseKeepAliveResponse{ID: req.ID, Header: &pb.ResponseHeader{}} |
| 125 | ls.hdr.fill(resp.Header) |
| 126 | |
| 127 | ttl, err := ls.le.LeaseRenew(stream.Context(), lease.LeaseID(req.ID)) |
| 128 | if err == lease.ErrLeaseNotFound { |
| 129 | err = nil |
| 130 | ttl = 0 |
| 131 | } |
| 132 | |
| 133 | if err != nil { |
| 134 | return togRPCError(err) |
| 135 | } |
| 136 | |
| 137 | resp.TTL = ttl |
| 138 | err = stream.Send(resp) |
| 139 | if err != nil { |
| 140 | if isClientCtxErr(stream.Context().Err(), err) { |
| 141 | plog.Debugf("failed to send lease keepalive response to gRPC stream (%q)", err.Error()) |
| 142 | } else { |
| 143 | plog.Warningf("failed to send lease keepalive response to gRPC stream (%q)", err.Error()) |
| 144 | } |
| 145 | return err |
| 146 | } |
| 147 | } |
| 148 | } |