From 44ab1028ce52866832ef9c39a0d567d2167c2ebe Mon Sep 17 00:00:00 2001
From: Andrey Slotin <andrey.slotin@instana.com>
Date: Wed, 5 Feb 2020 13:57:00 +0100
Subject: [PATCH 1/5] Fix typos in code comments

---
 sensor.go | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sensor.go b/sensor.go
index d40785df1..dcdc3fd11 100644
--- a/sensor.go
+++ b/sensor.go
@@ -20,7 +20,7 @@ type sensorS struct {
 var sensor *sensorS
 
 func (r *sensorS) init(options *Options) {
-	//sensor can be initialized explicit or implicit through OpenTracing global init
+	// sensor can be initialized explicitly or implicitly through OpenTracing global init
 	if r.meter == nil {
 		r.setOptions(options)
 		r.configureServiceName()
@@ -58,7 +58,7 @@ func (r *sensorS) configureServiceName() {
 	}
 }
 
-// InitSensor Intializes the sensor (without tracing) to begin collecting
+// InitSensor intializes the sensor (without tracing) to begin collecting
 // and reporting metrics.
 func InitSensor(options *Options) {
 	if sensor == nil {

From f3b35a5e88abfdfd163e83a5df3f0ec481bbd5be Mon Sep 17 00:00:00 2001
From: Andrey Slotin <andrey.slotin@instana.com>
Date: Wed, 5 Feb 2020 13:57:19 +0100
Subject: [PATCH 2/5] Return early from instana.InitSensor() if sensor has
 already been initialized

---
 sensor.go | 23 +++++++++++++----------
 1 file changed, 13 insertions(+), 10 deletions(-)

diff --git a/sensor.go b/sensor.go
index dcdc3fd11..59a241929 100644
--- a/sensor.go
+++ b/sensor.go
@@ -61,16 +61,19 @@ func (r *sensorS) configureServiceName() {
 // InitSensor intializes the sensor (without tracing) to begin collecting
 // and reporting metrics.
 func InitSensor(options *Options) {
-	if sensor == nil {
-		sensor = new(sensorS)
-		// If this environment variable is set, then override log level
-		_, ok := os.LookupEnv("INSTANA_DEBUG")
-		if ok {
-			options.LogLevel = Debug
-		}
+	if sensor != nil {
+		return
+	}
+
+	sensor = &sensorS{}
 
-		sensor.initLog()
-		sensor.init(options)
-		log.debug("initialized sensor")
+	// If this environment variable is set, then override log level
+	_, ok := os.LookupEnv("INSTANA_DEBUG")
+	if ok {
+		options.LogLevel = Debug
 	}
+
+	sensor.initLog()
+	sensor.init(options)
+	log.debug("initialized sensor")
 }

From 9176d36bfedaf33c9025c2c16adf1fc2916d6c4b Mon Sep 17 00:00:00 2001
From: Andrey Slotin <andrey.slotin@instana.com>
Date: Wed, 5 Feb 2020 13:59:42 +0100
Subject: [PATCH 3/5] Remove unused options getter from instana.Sensor

---
 sensor.go | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/sensor.go b/sensor.go
index 59a241929..14a1d792a 100644
--- a/sensor.go
+++ b/sensor.go
@@ -44,10 +44,6 @@ func (r *sensorS) setOptions(options *Options) {
 	}
 }
 
-func (r *sensorS) getOptions() *Options {
-	return r.options
-}
-
 func (r *sensorS) configureServiceName() {
 	if r.options != nil {
 		r.serviceName = r.options.Service

From cdd70111bfa6f1101c9017216548e2a87b02307e Mon Sep 17 00:00:00 2001
From: Andrey Slotin <andrey.slotin@instana.com>
Date: Wed, 5 Feb 2020 14:33:57 +0100
Subject: [PATCH 4/5] Use the value of INSTANA_SERVICE_NAME env var as a
 default service name

Allow to configure the service name via env variable instead of
falling back to the binary name immediately.
---
 sensor.go | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/sensor.go b/sensor.go
index 14a1d792a..99d3fae05 100644
--- a/sensor.go
+++ b/sensor.go
@@ -49,6 +49,10 @@ func (r *sensorS) configureServiceName() {
 		r.serviceName = r.options.Service
 	}
 
+	if r.serviceName == "" {
+		r.serviceName = os.Getenv("INSTANA_SERVICE_NAME")
+	}
+
 	if r.serviceName == "" {
 		r.serviceName = filepath.Base(os.Args[0])
 	}

From 40ab14401a470f3939a3e400c7bc3ce8ccf8f716 Mon Sep 17 00:00:00 2001
From: Andrey Slotin <andrey.slotin@instana.com>
Date: Wed, 5 Feb 2020 15:43:15 +0100
Subject: [PATCH 5/5] Prioritize service name passed through the env over the
 Options configuration

---
 sensor.go | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/sensor.go b/sensor.go
index 99d3fae05..afda3bab8 100644
--- a/sensor.go
+++ b/sensor.go
@@ -45,12 +45,13 @@ func (r *sensorS) setOptions(options *Options) {
 }
 
 func (r *sensorS) configureServiceName() {
-	if r.options != nil {
-		r.serviceName = r.options.Service
+	if name, ok := os.LookupEnv("INSTANA_SERVICE_NAME"); ok {
+		r.serviceName = name
+		return
 	}
 
-	if r.serviceName == "" {
-		r.serviceName = os.Getenv("INSTANA_SERVICE_NAME")
+	if r.options != nil {
+		r.serviceName = r.options.Service
 	}
 
 	if r.serviceName == "" {