Tracegen supports generating firehose spans (#1798)

- add 'firehose' flag for tracegen
- upgrade jaeger-client-go version to 2.18.0

Signed-off-by: jung <jung@uber.com>

Author: guo0693

Gopkg.toml

@@ -97,7 +97,7 @@ required = [
 
 [[constraint]]
   name = "github.com/uber/jaeger-client-go"
-  version = "^2.17.0"
+  version = "^2.18.0"
 
 [[constraint]]
   name = "github.com/uber/jaeger-lib"

internal/tracegen/config.go

@@ -30,6 +30,7 @@ type Config struct {
 	Traces   int
 	Marshal  bool
 	Debug    bool
+	Firehose bool
 	Pause    time.Duration
 	Duration time.Duration
 }
@@ -40,6 +41,7 @@ func (c *Config) Flags(fs *flag.FlagSet) {
 	fs.IntVar(&c.Traces, "traces", 1, "Number of traces to generate in each worker (ignored if duration is provided")
 	fs.BoolVar(&c.Marshal, "marshal", false, "Whether to marshal trace context via HTTP headers")
 	fs.BoolVar(&c.Debug, "debug", false, "Whether to set DEBUG flag on the spans to force sampling")
+	fs.BoolVar(&c.Firehose, "firehose", false, "Whether to set FIREHOSE flag on the spans to skip indexing")
 	fs.DurationVar(&c.Pause, "pause", time.Microsecond, "How long to pause before finishing trace")
 	fs.DurationVar(&c.Duration, "duration", 0, "For how long to run the test")
 }
@@ -61,6 +63,7 @@ func Run(c *Config, logger *zap.Logger) error {
 			traces:   c.Traces,
 			marshal:  c.Marshal,
 			debug:    c.Debug,
+			firehose: c.Firehose,
 			pause:    c.Pause,
 			duration: c.Duration,
 			running:  &running,

internal/tracegen/worker.go

@@ -22,6 +22,7 @@ import (
 
 	"github.com/opentracing/opentracing-go"
 	"github.com/opentracing/opentracing-go/ext"
+	"github.com/uber/jaeger-client-go"
 	"go.uber.org/zap"
 )
 
@@ -31,6 +32,7 @@ type worker struct {
 	traces   int             // how many traces the worker has to generate (only when duration==0)
 	marshal  bool            // whether the worker needs to marshal trace context via HTTP headers
 	debug    bool            // whether to set DEBUG flag on the spans
+	firehose bool            // whether to set FIREHOSE flag on the spans
 	duration time.Duration   // how long to run the test for (overrides `traces`)
 	pause    time.Duration   // how long to pause before finishing the trace
 	wg       *sync.WaitGroup // notify when done
@@ -55,6 +57,10 @@ func (w worker) simulateTraces() {
 			ext.SamplingPriority.Set(sp, 100)
 		}
 
+		if w.firehose {
+			jaeger.EnableFirehose(sp.(*jaeger.Span))
+		}
+
 		childCtx := sp.Context()
 		if w.marshal {
 			m := make(map[string]string)