Merge pull request #15628 from bergquist/move_tracing_infra

moves tracing packge into /infra

pkg/infra/tracing/tracing.go

@@ -0,0 +1,129 @@
+package tracing
+
+import (
+	"context"
+	"io"
+	"strings"
+
+	"github.com/grafana/grafana/pkg/log"
+	"github.com/grafana/grafana/pkg/registry"
+	"github.com/grafana/grafana/pkg/setting"
+
+	opentracing "github.com/opentracing/opentracing-go"
+	jaegercfg "github.com/uber/jaeger-client-go/config"
+)
+
+func init() {
+	registry.RegisterService(&TracingService{})
+}
+
+type TracingService struct {
+	enabled      bool
+	address      string
+	customTags   map[string]string
+	samplerType  string
+	samplerParam float64
+	log          log.Logger
+	closer       io.Closer
+
+	Cfg *setting.Cfg `inject:""`
+}
+
+func (ts *TracingService) Init() error {
+	ts.log = log.New("tracing")
+	ts.parseSettings()
+
+	if ts.enabled {
+		ts.initGlobalTracer()
+	}
+
+	return nil
+}
+
+func (ts *TracingService) parseSettings() {
+	var section, err = ts.Cfg.Raw.GetSection("tracing.jaeger")
+	if err != nil {
+		return
+	}
+
+	ts.address = section.Key("address").MustString("")
+	if ts.address != "" {
+		ts.enabled = true
+	}
+
+	ts.customTags = splitTagSettings(section.Key("always_included_tag").MustString(""))
+	ts.samplerType = section.Key("sampler_type").MustString("")
+	ts.samplerParam = section.Key("sampler_param").MustFloat64(1)
+}
+
+func (ts *TracingService) initGlobalTracer() error {
+	cfg := jaegercfg.Configuration{
+		ServiceName: "grafana",
+		Disabled:    !ts.enabled,
+		Sampler: &jaegercfg.SamplerConfig{
+			Type:  ts.samplerType,
+			Param: ts.samplerParam,
+		},
+		Reporter: &jaegercfg.ReporterConfig{
+			LogSpans:           false,
+			LocalAgentHostPort: ts.address,
+		},
+	}
+
+	jLogger := &jaegerLogWrapper{logger: log.New("jaeger")}
+
+	options := []jaegercfg.Option{}
+	options = append(options, jaegercfg.Logger(jLogger))
+
+	for tag, value := range ts.customTags {
+		options = append(options, jaegercfg.Tag(tag, value))
+	}
+
+	tracer, closer, err := cfg.NewTracer(options...)
+	if err != nil {
+		return err
+	}
+
+	opentracing.InitGlobalTracer(tracer)
+
+	ts.closer = closer
+
+	return nil
+}
+
+func (ts *TracingService) Run(ctx context.Context) error {
+	<-ctx.Done()
+
+	if ts.closer != nil {
+		ts.log.Info("Closing tracing")
+		ts.closer.Close()
+	}
+
+	return nil
+}
+
+func splitTagSettings(input string) map[string]string {
+	res := map[string]string{}
+
+	tags := strings.Split(input, ",")
+	for _, v := range tags {
+		kv := strings.Split(v, ":")
+		if len(kv) > 1 {
+			res[kv[0]] = kv[1]
+		}
+	}
+
+	return res
+}
+
+type jaegerLogWrapper struct {
+	logger log.Logger
+}
+
+func (jlw *jaegerLogWrapper) Error(msg string) {
+	jlw.logger.Error(msg)
+}
+
+func (jlw *jaegerLogWrapper) Infof(msg string, args ...interface{}) {
+	jlw.logger.Info(msg, args)
+}

pkg/infra/tracing/tracing_test.go

@@ -0,0 +1,36 @@
+package tracing
+
+import "testing"
+
+func TestGroupSplit(t *testing.T) {
+	tests := []struct {
+		input    string
+		expected map[string]string
+	}{
+		{
+			input: "tag1:value1,tag2:value2",
+			expected: map[string]string{
+				"tag1": "value1",
+				"tag2": "value2",
+			},
+		},
+		{
+			input:    "",
+			expected: map[string]string{},
+		},
+		{
+			input:    "tag1",
+			expected: map[string]string{},
+		},
+	}
+
+	for _, test := range tests {
+		tags := splitTagSettings(test.input)
+		for k, v := range test.expected {
+			value, exists := tags[k]
+			if !exists || value != v {
+				t.Errorf("tags does not match %v ", test)
+			}
+		}
+	}
+}