/
span.go
276 lines (249 loc) · 8.44 KB
/
span.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
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
package instrumentation
import (
"context"
"fmt"
"log"
"time"
mergelogpb "github.com/eppppi/k8s-cp-dt/mergelog/src/pkg/grpc"
"github.com/google/uuid"
"google.golang.org/grpc"
"google.golang.org/grpc/credentials/insecure"
timestamppb "google.golang.org/protobuf/types/known/timestamppb"
)
type traceContextKey string
const (
kOC_PARENTID_KEY traceContextKey = "eppppi.github.io/koc-parentid"
kOC_TCTX_KEY traceContextKey = "eppppi.github.io/koc-tctx"
)
func GetParentIdFromContext(ctx context.Context) string {
if val, ok := ctx.Value(kOC_PARENTID_KEY).(string); !ok {
return ""
} else {
return val
}
}
func SetParentIdToContext(ctx context.Context, parentId string) context.Context {
return context.WithValue(ctx, kOC_PARENTID_KEY, parentId)
}
// GetTraceContextsFromContext returns trace contexts from ctx.
// If ctx is nil, returns nil. If there are any nil tctxs, they are ignored.
// (non-nil tctxs are returned, and len() of returned slice is the number of non-nil tctxs)
func GetTraceContextsFromContext(ctx context.Context) []*TraceContext {
if ctx == nil {
log.Println("EPPPPI-DEBUG: GetTraceContextsFromContext(): ctx is nil")
return nil
}
if tctxs, ok := ctx.Value(kOC_TCTX_KEY).([]*TraceContext); !ok {
return nil
} else {
retTctxs := make([]*TraceContext, 0)
for _, tctx := range tctxs {
if tctx != nil {
retTctxs = append(retTctxs, tctx)
}
}
return retTctxs
}
}
func SetTraceContextsToContext(ctx context.Context, tctxs []*TraceContext) context.Context {
return context.WithValue(ctx, kOC_TCTX_KEY, tctxs)
}
func AddTraceContextToContext(ctx context.Context, tctx *TraceContext) context.Context {
tctxs := GetTraceContextsFromContext(ctx)
tctxs = append(tctxs, tctx)
return SetTraceContextsToContext(ctx, tctxs)
}
var (
spanCh chan *mergelogpb.Span
mergelogCh chan *mergelogpb.Mergelog
)
const (
CHANNEL_SIZE = 100
)
// InitSender initializes a sender (gRPC client).
// If wait is true, this func waits until setup is done.
func InitSender(endpoint string, timeout time.Duration, _numAncCpids int) (<-chan error, func()) {
numAncCpids = _numAncCpids
doneCh := make(chan struct{})
spanCh = make(chan *mergelogpb.Span, CHANNEL_SIZE)
mergelogCh = make(chan *mergelogpb.Mergelog, CHANNEL_SIZE)
setupDoneCh := make(chan error)
finishCh := make(chan struct{})
go runSender(doneCh, endpoint, spanCh, mergelogCh, setupDoneCh, finishCh, timeout)
return setupDoneCh, func() {
doneCh <- struct{}{}
// wait until sender is shutdown
<-finishCh
}
}
// Span is a span that is to be converted to the Span struct of protobuf
type Span struct {
cpid string
startTime time.Time
endTime time.Time
service string
objectKind string
objectName string
message string
spanId string
parentId string
}
// Start starts a span. If cpid == "" and ctx has no trace context, returns an error.
func Start(ctx context.Context, cpid, service, objKind, objName, msg string) (context.Context, *Span, error) {
if cpid == "" {
tctxs := GetTraceContextsFromContext(ctx)
if len(tctxs) == 0 {
return ctx, nil, fmt.Errorf("cpid = \"\", and no trace context found in ctx")
}
// TODO (REFACTOR): use all of tctxs instead of only one
// TODO (REFACTOR) (idea): change Span to embrace multiple tctxs so that we don't need to merge tctxs here every time
cpid = tctxs[0].GetCpid()
}
// 古いctxには、呼び出し側の関数のspanIdが入っている
// newCtxには、出力されるspanと同じ情報が入っている
spanId, _ := uuid.NewRandom()
span := &Span{
cpid: cpid,
startTime: time.Now(),
service: service,
objectKind: objKind,
objectName: objName,
message: msg,
spanId: spanId.String(), // 新しいspanIdを入れる
parentId: GetParentIdFromContext(ctx), // 古いctxのspanIdを入れる
}
newCtx := SetParentIdToContext(ctx, spanId.String())
return newCtx, span, nil
}
// End ends a span
func (s *Span) End() {
s.endTime = time.Now()
// push to channel
spanCh <- s.ToProtoSpan()
}
// GenerateNewTctxAndSendMergelog generates a new trace context. if retTctx is nil, no mergelog is sent.
func MergeAndSendMergelog(sourceTctxs []*TraceContext, causeMsg, by string) *TraceContext {
return mergeAndSendMergelog(sourceTctxs, causeMsg, by)
}
// generateNewTctxAndSendMergelog generates a new trace context. if retTctx is nil, no mergelog is sent.
func mergeAndSendMergelog(sourceTctxs []*TraceContext, causeMsg, by string) *TraceContext {
log.Println("EPPPPI-DEBUG: mergeAndSendMergelog() started")
defer log.Println("EPPPPI-DEBUG: mergeAndSendMergelog() ended")
newSourceTctxs := make([]*TraceContext, 0)
for i := 0; i < len(sourceTctxs); i++ {
if err := sourceTctxs[i].validateTctx(); err != nil {
log.Println("validation error, skipping this tctx:", err)
} else {
newSourceTctxs = append(newSourceTctxs, sourceTctxs[i].DeepCopyTraceContext())
}
}
if len(newSourceTctxs) == 0 {
return nil
} else if len(newSourceTctxs) == 1 {
return newSourceTctxs[0]
}
retTctx, newCpid, sourceCpids := mergeTctxs(newSourceTctxs)
log.Println("EPPPPI-DEBUG= retTctx in mergeAndSendMergelog():", retTctx)
if sourceCpids != nil {
err := sendMergelog(newCpid, sourceCpids, mergelogpb.CauseType_CAUSE_TYPE_MERGE, causeMsg, by)
if err != nil {
panic(err) // should not happen because of prior validation
}
}
return retTctx
}
// GenerateAndSendMergelog generates a mergelog and push it to channel
func sendMergelog(newCpid string, sourceCpids []string, causeType mergelogpb.CauseType, causeMsg, by string) error {
log.Println("EPPPPI-DEBUG: sendMergelog() invoked")
// validate cpids
if newCpid == "" {
log.Println("EPPPPI-DEBUG (sendMergelog()): newCpid is empty string")
return fmt.Errorf("newCpid is empty string")
}
for _, sourceCpid := range sourceCpids {
if sourceCpid == "" {
log.Println("EPPPPI-DEBUG (sendMergelog()): one of sourceCpid is empty string")
return fmt.Errorf("one of sourceCpid is empty string")
}
}
srcCpids := make([]*mergelogpb.CPID, 0)
for _, cpid := range sourceCpids {
srcCpids = append(srcCpids, &mergelogpb.CPID{Cpid: cpid})
}
mergelog := &mergelogpb.Mergelog{
NewCpid: &mergelogpb.CPID{Cpid: newCpid},
SourceCpids: srcCpids,
Time: timestamppb.New(time.Now()),
CauseType: causeType,
CauseMessage: causeMsg,
By: by,
}
log.Println("EPPPPI-DEBUG: mergelog sent into mergelogCh")
mergelogCh <- mergelog
return nil
}
// ToProtoSpan converts a span to the Span struct of protobuf
func (s *Span) ToProtoSpan() *mergelogpb.Span {
return &mergelogpb.Span{
Cpid: &mergelogpb.CPID{Cpid: s.cpid},
StartTime: timestamppb.New(s.startTime),
EndTime: timestamppb.New(s.endTime),
Service: s.service,
ObjectKind: s.objectKind,
ObjectName: s.objectName,
Message: s.message,
SpanId: s.spanId,
ParentId: s.parentId,
}
}
// RunSender runs a sender.
// This func is intended to be called as a goroutine.
// ctx is a context that is used to stop this func.
func runSender(doneCh <-chan struct{}, endpoint string, spanCh <-chan *mergelogpb.Span, mergelogCh <-chan *mergelogpb.Mergelog, setupDoneCh chan<- error, finishCh chan<- struct{}, timeout time.Duration) {
log.Println("runSender() started")
ctx, cancel := context.WithTimeout(context.Background(), timeout)
defer cancel()
// TODO(improve): 毎回送信するのではなく、一定時間ごとに送信するようにする
conn, err := grpc.DialContext(
ctx,
endpoint,
grpc.WithTransportCredentials(insecure.NewCredentials()),
grpc.WithBlock(),
)
if err != nil {
setupDoneCh <- fmt.Errorf("connection failed: %v: the trace-server is not running or the endpoint is wrong", err)
finishCh <- struct{}{}
return
} else {
log.Println("Connection succeeded")
}
defer conn.Close()
client := mergelogpb.NewMergelogServiceClient(conn)
setupDoneCh <- nil
log.Println("EPPPPI-DEBUG: runSender() setupDoneCh <- nil sent")
for {
select {
case <-doneCh:
// TODO: graceful shutdown (wait until all channels are empty)
log.Println("finishing sender")
finishCh <- struct{}{}
return
case span := <-spanCh:
req := &mergelogpb.PostSpansRequest{
Spans: []*mergelogpb.Span{span},
}
_, err := client.PostSpans(context.Background(), req)
if err != nil {
log.Println(err)
}
case mergelog := <-mergelogCh:
req := &mergelogpb.MergelogRequest{
Mergelogs: []*mergelogpb.Mergelog{mergelog},
}
_, err := client.PostMergelogs(context.Background(), req)
if err != nil {
log.Println(err)
}
}
}
}