Tracing: add Gen128Bit support for jaeger

Signed-off-by: Jimmie Han <[email protected]>

docs/tracing.md

@@ -94,6 +94,7 @@ config:
   password: ""
   agent_host: ""
   agent_port: 0
+  traceid_128bit: false
 ```
 
 ### Stackdriver

pkg/tracing/jaeger/config_yaml.go

@@ -37,6 +37,7 @@ type Config struct {
 	Password               string        `yaml:"password"`
 	AgentHost              string        `yaml:"agent_host"`
 	AgentPort              int           `yaml:"agent_port"`
+	Gen128Bit              bool          `yaml:"traceid_128bit"`
 }
 
 // ParseConfigFromYaml uses config YAML to set the tracer's Configuration.
@@ -57,6 +58,10 @@ func ParseConfigFromYaml(cfg []byte) (*config.Configuration, error) {
 		c.RPCMetrics = conf.RPCMetrics
 	}
 
+	if conf.Gen128Bit {
+		c.Gen128Bit = conf.Gen128Bit
+	}
+
 	if conf.Disabled {
 		c.Disabled = conf.Disabled
 	}