Rename gomu to micro (#2325)

* Rename Gomu to Micro

* docs: Remove license reference in CLI's README

cmd/micro/debug/trace/jaeger/jaeger.go

@@ -0,0 +1,47 @@
+package jaeger
+
+import (
+	"io"
+
+	"github.com/opentracing/opentracing-go"
+	jaegercfg "github.com/uber/jaeger-client-go/config"
+)
+
+// NewTracer returns a new Jaeger tracer based on the current configuration,
+// using the given options, and a closer func that can be used to flush buffers
+// before shutdown.
+func NewTracer(opts ...Option) (opentracing.Tracer, io.Closer, error) {
+	options := newOptions(opts...)
+
+	cfg := &jaegercfg.Configuration{}
+	if options.FromEnv {
+		c, err := jaegercfg.FromEnv()
+		if err != nil {
+			return nil, nil, err
+		}
+		cfg = c
+	}
+
+	if options.Name != "" {
+		cfg.ServiceName = options.Name
+	}
+
+	var jOptions []jaegercfg.Option
+	if options.Logger != nil {
+		jOptions = append(jOptions, jaegercfg.Logger(options.Logger))
+	}
+	if options.Metrics != nil {
+		jOptions = append(jOptions, jaegercfg.Metrics(options.Metrics))
+	}
+
+	tracer, closer, err := cfg.NewTracer(jOptions...)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	if options.GlobalTracer {
+		opentracing.SetGlobalTracer(tracer)
+	}
+
+	return tracer, closer, nil
+}

cmd/micro/debug/trace/jaeger/options.go

@@ -0,0 +1,76 @@
+package jaeger
+
+import (
+	"github.com/uber/jaeger-client-go"
+	"github.com/uber/jaeger-lib/metrics"
+)
+
+var (
+	// DefaultLogger is the default Jaeger logger.
+	DefaultLogger = jaeger.StdLogger
+
+	// DefaultMetrics is the default Jaeger metrics factory.
+	DefaultMetrics = metrics.NullFactory
+)
+
+// Options represents the options passed to the Jaeger tracer.
+type Options struct {
+	Name         string
+	FromEnv      bool
+	GlobalTracer bool
+	Logger       jaeger.Logger
+	Metrics      metrics.Factory
+}
+
+// Option manipulates the passed Options struct.
+type Option func(o *Options)
+
+func newOptions(opts ...Option) Options {
+	options := Options{
+		Logger:  DefaultLogger,
+		Metrics: DefaultMetrics,
+	}
+
+	for _, o := range opts {
+		o(&options)
+	}
+
+	return options
+}
+
+// Name sets the service name for the Jaeger tracer.
+func Name(s string) Option {
+	return func(o *Options) {
+		o.Name = s
+	}
+}
+
+// FromEnv determines whether the Jaeger tracer configuration should use
+// environment variables.
+func FromEnv(e bool) Option {
+	return func(o *Options) {
+		o.FromEnv = e
+	}
+}
+
+// GlobalTracer determines whether the Jaeger tracer should be set as the
+// global tracer.
+func GlobalTracer(e bool) Option {
+	return func(o *Options) {
+		o.GlobalTracer = e
+	}
+}
+
+// Logger sets the logger for the Jaeger tracer.
+func Logger(l jaeger.Logger) Option {
+	return func(o *Options) {
+		o.Logger = l
+	}
+}
+
+// Metrics sets the metrics factory for the Jaeger tracer.
+func Metrics(m metrics.Factory) Option {
+	return func(o *Options) {
+		o.Metrics = m
+	}
+}

cmd/micro/debug/trace/trace.go

@@ -0,0 +1,20 @@
+package trace
+
+import (
+	"context"
+	"runtime"
+
+	"github.com/opentracing/opentracing-go"
+)
+
+// NewSpan accepts a context and returns an OpenTracing span. Can be used to
+// nest spans.
+func NewSpan(ctx context.Context) opentracing.Span {
+	pc := make([]uintptr, 10) // at least 1 entry needed
+	runtime.Callers(2, pc)
+	span := opentracing.StartSpan(
+		runtime.FuncForPC(pc[0]).Name(),
+		opentracing.ChildOf(opentracing.SpanFromContext(ctx).Context()),
+	)
+	return span
+}