-
Notifications
You must be signed in to change notification settings - Fork 117
/
fiber.go
181 lines (150 loc) · 5.91 KB
/
fiber.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
package otelfiber
import (
"context"
"net/http"
"time"
"github.com/gofiber/fiber/v2"
"github.com/gofiber/fiber/v2/utils"
otelcontrib "go.opentelemetry.io/contrib"
"go.opentelemetry.io/otel"
"go.opentelemetry.io/otel/attribute"
"go.opentelemetry.io/otel/metric"
"go.opentelemetry.io/otel/propagation"
semconv "go.opentelemetry.io/otel/semconv/v1.12.0"
oteltrace "go.opentelemetry.io/otel/trace"
)
const (
tracerKey = "gofiber-contrib-tracer-fiber"
instrumentationName = "github.com/gofiber/contrib/otelfiber"
MetricNameHttpServerDuration = "http.server.duration"
MetricNameHttpServerRequestSize = "http.server.request.size"
MetricNameHttpServerResponseSize = "http.server.response.size"
MetricNameHttpServerActiveRequests = "http.server.active_requests"
// Unit constants for deprecated metric units
UnitDimensionless = "1"
UnitBytes = "By"
UnitMilliseconds = "ms"
)
// Middleware returns fiber handler which will trace incoming requests.
func Middleware(opts ...Option) fiber.Handler {
cfg := config{
collectClientIP: true,
}
for _, opt := range opts {
opt.apply(&cfg)
}
if cfg.TracerProvider == nil {
cfg.TracerProvider = otel.GetTracerProvider()
}
tracer := cfg.TracerProvider.Tracer(
instrumentationName,
oteltrace.WithInstrumentationVersion(otelcontrib.Version()),
)
if cfg.MeterProvider == nil {
cfg.MeterProvider = otel.GetMeterProvider()
}
meter := cfg.MeterProvider.Meter(
instrumentationName,
metric.WithInstrumentationVersion(otelcontrib.Version()),
)
httpServerDuration, err := meter.Float64Histogram(MetricNameHttpServerDuration, metric.WithUnit(UnitMilliseconds), metric.WithDescription("measures the duration inbound HTTP requests"))
if err != nil {
otel.Handle(err)
}
httpServerRequestSize, err := meter.Int64Histogram(MetricNameHttpServerRequestSize, metric.WithUnit(UnitBytes), metric.WithDescription("measures the size of HTTP request messages"))
if err != nil {
otel.Handle(err)
}
httpServerResponseSize, err := meter.Int64Histogram(MetricNameHttpServerResponseSize, metric.WithUnit(UnitBytes), metric.WithDescription("measures the size of HTTP response messages"))
if err != nil {
otel.Handle(err)
}
httpServerActiveRequests, err := meter.Int64UpDownCounter(MetricNameHttpServerActiveRequests, metric.WithUnit(UnitDimensionless), metric.WithDescription("measures the number of concurrent HTTP requests that are currently in-flight"))
if err != nil {
otel.Handle(err)
}
if cfg.Propagators == nil {
cfg.Propagators = otel.GetTextMapPropagator()
}
if cfg.SpanNameFormatter == nil {
cfg.SpanNameFormatter = defaultSpanNameFormatter
}
return func(c *fiber.Ctx) error {
// Don't execute middleware if Next returns true
if cfg.Next != nil && cfg.Next(c) {
return c.Next()
}
c.Locals(tracerKey, tracer)
savedCtx, cancel := context.WithCancel(c.UserContext())
start := time.Now()
requestMetricsAttrs := httpServerMetricAttributesFromRequest(c, cfg)
httpServerActiveRequests.Add(savedCtx, 1, metric.WithAttributes(requestMetricsAttrs...))
responseMetricAttrs := make([]attribute.KeyValue, len(requestMetricsAttrs))
copy(responseMetricAttrs, requestMetricsAttrs)
reqHeader := make(http.Header)
c.Request().Header.VisitAll(func(k, v []byte) {
reqHeader.Add(string(k), string(v))
})
ctx := cfg.Propagators.Extract(savedCtx, propagation.HeaderCarrier(reqHeader))
opts := []oteltrace.SpanStartOption{
oteltrace.WithAttributes(httpServerTraceAttributesFromRequest(c, cfg)...),
oteltrace.WithSpanKind(oteltrace.SpanKindServer),
}
// temporary set to c.Path() first
// update with c.Route().Path after c.Next() is called
// to get pathRaw
spanName := utils.CopyString(c.Path())
ctx, span := tracer.Start(ctx, spanName, opts...)
defer span.End()
// pass the span through userContext
c.SetUserContext(ctx)
// serve the request to the next middleware
if err := c.Next(); err != nil {
span.RecordError(err)
// invokes the registered HTTP error handler
// to get the correct response status code
_ = c.App().Config().ErrorHandler(c, err)
}
// extract common attributes from response
responseAttrs := append(
semconv.HTTPAttributesFromHTTPStatusCode(c.Response().StatusCode()),
semconv.HTTPRouteKey.String(c.Route().Path), // no need to copy c.Route().Path: route strings should be immutable across app lifecycle
)
var responseSize int64
requestSize := int64(len(c.Request().Body()))
if c.GetRespHeader("Content-Type") != "text/event-stream" {
responseSize = int64(len(c.Response().Body()))
}
defer func() {
responseMetricAttrs = append(
responseMetricAttrs,
responseAttrs...)
httpServerActiveRequests.Add(savedCtx, -1, metric.WithAttributes(requestMetricsAttrs...))
httpServerDuration.Record(savedCtx, float64(time.Since(start).Microseconds())/1000, metric.WithAttributes(responseMetricAttrs...))
httpServerRequestSize.Record(savedCtx, requestSize, metric.WithAttributes(responseMetricAttrs...))
httpServerResponseSize.Record(savedCtx, responseSize, metric.WithAttributes(responseMetricAttrs...))
c.SetUserContext(savedCtx)
cancel()
}()
span.SetAttributes(
append(
responseAttrs,
semconv.HTTPResponseContentLengthKey.Int64(responseSize),
)...)
span.SetName(cfg.SpanNameFormatter(c))
spanStatus, spanMessage := semconv.SpanStatusFromHTTPStatusCodeAndSpanKind(c.Response().StatusCode(), oteltrace.SpanKindServer)
span.SetStatus(spanStatus, spanMessage)
//Propagate tracing context as headers in outbound response
tracingHeaders := make(propagation.HeaderCarrier)
cfg.Propagators.Inject(c.UserContext(), tracingHeaders)
for _, headerKey := range tracingHeaders.Keys() {
c.Set(headerKey, tracingHeaders.Get(headerKey))
}
return nil
}
}
// defaultSpanNameFormatter is the default formatter for spans created with the fiber
// integration. Returns the route pathRaw
func defaultSpanNameFormatter(ctx *fiber.Ctx) string {
return ctx.Route().Path
}