-
Notifications
You must be signed in to change notification settings - Fork 684
/
grpc-agent.go
217 lines (185 loc) · 4.54 KB
/
grpc-agent.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
package services
import (
"context"
"encoding/json"
"fmt"
"io"
"io/ioutil"
"net/http"
"os"
"os/signal"
"strconv"
"sync"
"syscall"
"time"
"google.golang.org/grpc"
"google.golang.org/grpc/codes"
"google.golang.org/grpc/metadata"
"google.golang.org/grpc/status"
"github.com/datawire/dlib/dhttp"
"github.com/datawire/dlib/dlog"
"github.com/emissary-ingress/emissary/v3/pkg/api/agent"
)
type GRPCAgent struct {
Port int16
}
func (a *GRPCAgent) Start(ctx context.Context) <-chan bool {
wg := &sync.WaitGroup{}
var opts []grpc.ServerOption
if sizeStr := os.Getenv("KAT_GRPC_MAX_RECV_MSG_SIZE"); sizeStr != "" {
size, err := strconv.Atoi(sizeStr)
if err == nil {
dlog.Printf(ctx, "setting gRPC MaxRecvMsgSize to %d bytes", size)
opts = append(opts, grpc.MaxRecvMsgSize(size))
}
}
grpcHandler := grpc.NewServer(opts...)
dir := &director{}
agent.RegisterDirectorServer(grpcHandler, dir)
sc := &dhttp.ServerConfig{
Handler: grpcHandler,
}
grpcErrChan := make(chan error)
httpErrChan := make(chan error)
ctx, cancel := context.WithCancel(ctx)
wg.Add(2)
go func() {
defer wg.Done()
dlog.Print(ctx, "starting GRPC agentcom...")
if err := sc.ListenAndServe(ctx, fmt.Sprintf(":%d", a.Port)); err != nil {
select {
case grpcErrChan <- err:
default:
}
}
}()
srv := &http.Server{Addr: ":3001"}
http.HandleFunc("/lastSnapshot", func(w http.ResponseWriter, r *http.Request) {
lastSnap := dir.GetLastSnapshot()
if lastSnap == nil {
w.WriteHeader(http.StatusNotFound)
return
}
ret, err := json.Marshal(lastSnap)
if err != nil {
w.WriteHeader(http.StatusInternalServerError)
return
}
w.WriteHeader(http.StatusOK)
_, _ = w.Write(ret)
})
go func() {
defer wg.Done()
dlog.Print(ctx, "Starting http server")
if err := srv.ListenAndServe(); err != http.ErrServerClosed {
select {
case httpErrChan <- err:
default:
}
}
}()
exited := make(chan bool)
go func() {
c := make(chan os.Signal, 1)
signal.Notify(c, os.Interrupt, syscall.SIGTERM)
select {
case err := <-grpcErrChan:
dlog.Errorf(ctx, "GRPC service died: %+v", err)
panic(err) // TODO: do something better
case err := <-httpErrChan:
dlog.Errorf(ctx, "http service died: %+v", err)
panic(err) // TODO: do something better
case <-c:
dlog.Print(ctx, "Received shutdown")
}
ctx, timeout := context.WithTimeout(ctx, time.Second*30)
defer timeout()
cancel()
grpcHandler.GracefulStop()
_ = srv.Shutdown(ctx)
wg.Wait()
close(exited)
}()
return exited
}
type director struct {
agent.UnimplementedDirectorServer
lastSnapshot *agent.Snapshot
}
func (d *director) GetLastSnapshot() *agent.Snapshot {
return d.lastSnapshot
}
// Report is invoked when a new report with a snapshot arrives
func (d *director) Report(ctx context.Context, snapshot *agent.Snapshot) (*agent.SnapshotResponse, error) {
err := checkContext(ctx)
if err != nil {
return nil, err
}
dlog.Print(ctx, "Received snapshot")
err = writeSnapshot(snapshot)
if err != nil {
return nil, err
}
d.lastSnapshot = snapshot
return &agent.SnapshotResponse{}, nil
}
func (d *director) Retrieve(agentID *agent.Identity, stream agent.Director_RetrieveServer) error {
return nil
}
func checkContext(ctx context.Context) error {
md, ok := metadata.FromIncomingContext(ctx)
if !ok {
dlog.Print(ctx, "No metadata found, not allowing request")
err := status.Error(codes.PermissionDenied, "Missing grpc metadata")
return err
}
apiKeyValues := md.Get("x-ambassador-api-key")
if len(apiKeyValues) == 0 || apiKeyValues[0] == "" {
dlog.Print(ctx, "api key found, not allowing request")
err := status.Error(codes.PermissionDenied, "Missing api key")
return err
}
return nil
}
func writeSnapshot(snapshot *agent.Snapshot) error {
snapBytes, err := json.Marshal(snapshot)
if err != nil {
return err
}
err = ioutil.WriteFile("/tmp/snapshot.json", snapBytes, 0644)
if err != nil {
return err
}
return nil
}
func (d *director) ReportStream(server agent.Director_ReportStreamServer) error {
err := checkContext(server.Context())
if err != nil {
return err
}
var data []byte
for {
msg, err := server.Recv()
data = append(data, msg.GetChunk()...)
if err != nil {
if err == io.EOF {
break
} else {
return err
}
}
}
var snapshot agent.Snapshot
err = json.Unmarshal(data, &snapshot)
if err != nil {
return err
}
dlog.Print(server.Context(), "Received snapshot")
err = writeSnapshot(&snapshot)
if err != nil {
return err
}
response := &agent.SnapshotResponse{}
err = server.SendMsg(response)
return err
}