License Key? Api key? Neither works?

[ankon]

The README is really confusing:

This example code assumes you've set the the NEW_RELIC_LICENSE_KEY environment variable to your [license key](https://docs.newrelic.com/docs/apis/intro-apis/new-relic-api-keys/#ingest-license-key). A larger example is provided in [examples/server/main.go](https://github.com/newrelic/newrelic-telemetry-sdk-go/blob/master/examples/server/main.go).

...
	h, err := telemetry.NewHarvester(telemetry.ConfigAPIKey(os.Getenv("NEW_RELIC_LICENSE_KEY")))

1. There are quite some differences between license keys and API keys, so it looks odd that these would be treated the same here, see for instance https://docs.newrelic.com/docs/apis/intro-apis/new-relic-api-keys/. But, maybe the code is checking the type based on the prefix and then "does the right thing?"
2. Looking at https://discuss.newrelic.com/t/getting-403-when-posting-data-to-metrics-api/143663 it seems one actually could use a license key (using x-license-key instead of the api-key header), which is IMHO preferable. API keys are tied to users, but I don't want my app/service to stop reporting metrics just because the original developer leaves my company and I deactivate their account. I also don't want to fake up users like [email protected] or such.
3. ... and, it seems that regardless of which of the keys (license key, installer user key, or newly created user key) I add here, I always get a 403 without much explanation.

[ankon]

I'm going to try to "hack" in the change to use the x-license-key header, if that works I guess it could make sense to offer both options and clarify the README.

[ankon]

Something like this:

diff --git a/README.md b/README.md
index a8bff49..e4f0e21 100644
--- a/README.md
+++ b/README.md
@@ -51,8 +51,8 @@ import (
 )
 
 func main() {
-	// First create a Harvester.  APIKey is the only required field.
-	h, err := telemetry.NewHarvester(telemetry.ConfigAPIKey(os.Getenv("NEW_RELIC_LICENSE_KEY")))
+	// First create a Harvester.  Either LicenseKey or APIKey must be provided.
+	h, err := telemetry.NewHarvester(telemetry.ConfigLicenseKey(os.Getenv("NEW_RELIC_LICENSE_KEY")))
 	if err != nil {
 		fmt.Println(err)
 	}
diff --git a/telemetry/config.go b/telemetry/config.go
index 56c8ce1..5889771 100644
--- a/telemetry/config.go
+++ b/telemetry/config.go
@@ -13,8 +13,12 @@ import (
 
 // Config customizes the behavior of a Harvester.
 type Config struct {
-	// APIKey is required and refers to your New Relic Insert API key.
+	// APIKey refers to your New Relic Insert API key.
+	// One of APIKey or LicenseKey is required
 	APIKey string
+	// LicenseKey refers to your New Relic License key.
+	// One of APIKey or LicenseKey is required
+	LicenseKey string
 	// Client is the http.Client used for making requests.
 	Client *http.Client
 	// HarvestTimeout is the total amount of time including retries that the
@@ -55,7 +59,7 @@ type Config struct {
 	ProductVersion string
 }
 
-// ConfigAPIKey sets the Config's APIKey which is required and refers to your
+// ConfigAPIKey sets the Config's APIKey which refers to your
 // New Relic Insert API key.
 func ConfigAPIKey(key string) func(*Config) {
 	return func(cfg *Config) {
@@ -63,6 +67,14 @@ func ConfigAPIKey(key string) func(*Config) {
 	}
 }
 
+// ConfigLicenseKey sets the Config's LicenseKey which refers to your
+// New Relic License key.
+func ConfigLicenseKey(key string) func(*Config) {
+	return func(cfg *Config) {
+		cfg.LicenseKey = key
+	}
+}
+
 // ConfigCommonAttributes adds the given attributes to the Config's
 // CommonAttributes.
 func ConfigCommonAttributes(attributes map[string]interface{}) func(*Config) {
diff --git a/telemetry/harvester.go b/telemetry/harvester.go
index 5e81ad9..0587afd 100644
--- a/telemetry/harvester.go
+++ b/telemetry/harvester.go
@@ -51,7 +51,7 @@ const (
 )
 
 var (
-	errAPIKeyUnset = errors.New("APIKey is required")
+	errAPIKeyUnset = errors.New("APIKey or LicenseKey is required")
 )
 
 // NewHarvester creates a new harvester.
@@ -65,7 +65,12 @@ func NewHarvester(options ...func(*Config)) (*Harvester, error) {
 		opt(&cfg)
 	}
 
-	if cfg.APIKey == "" {
+	var apiKeyOption ClientOption
+	if cfg.APIKey != "" {
+		apiKeyOption = WithInsertKey(cfg.APIKey)
+	} else if cfg.LicenseKey != "" {
+		apiKeyOption = WithLicenseKey(cfg.LicenseKey)
+	} else {
 		return nil, errAPIKeyUnset
 	}
 
@@ -97,7 +102,7 @@ func NewHarvester(options ...func(*Config)) (*Harvester, error) {
 	userAgent := "harvester " + h.config.userAgent()
 
 	h.spanRequestFactory, err = NewSpanRequestFactory(
-		WithInsertKey(h.config.APIKey),
+		apiKeyOption,
 		withScheme(spanURL.Scheme),
 		WithEndpoint(spanURL.Host),
 		WithUserAgent(userAgent),
@@ -112,7 +117,7 @@ func NewHarvester(options ...func(*Config)) (*Harvester, error) {
 	}
 
 	h.metricRequestFactory, err = NewMetricRequestFactory(
-		WithInsertKey(h.config.APIKey),
+		apiKeyOption,
 		withScheme(metricURL.Scheme),
 		WithEndpoint(metricURL.Host),
 		WithUserAgent(userAgent),
@@ -127,7 +132,7 @@ func NewHarvester(options ...func(*Config)) (*Harvester, error) {
 	}
 
 	h.eventRequestFactory, err = NewEventRequestFactory(
-		WithInsertKey(h.config.APIKey),
+		apiKeyOption,
 		withScheme(eventURL.Scheme),
 		WithEndpoint(eventURL.Host),
 		WithUserAgent(userAgent),
@@ -142,7 +147,7 @@ func NewHarvester(options ...func(*Config)) (*Harvester, error) {
 	}
 
 	h.logRequestFactory, err = NewLogRequestFactory(
-		WithInsertKey(h.config.APIKey),
+		apiKeyOption,
 		withScheme(logURL.Scheme),
 		WithEndpoint(logURL.Host),
 		WithUserAgent(userAgent),
@@ -153,7 +158,8 @@ func NewHarvester(options ...func(*Config)) (*Harvester, error) {
 
 	h.config.logDebug(map[string]interface{}{
 		"event":                  "harvester created",
-		"api-key":                sanitizeAPIKeyForLogging(h.config.APIKey),
+		"api-key":                sanitizeKeyForLogging(h.config.APIKey),
+		"license-key":            sanitizeKeyForLogging(h.config.LicenseKey),
 		"harvest-period-seconds": h.config.HarvestPeriod.Seconds(),
 		"metrics-url-override":   h.config.MetricsURLOverride,
 		"spans-url-override":     h.config.SpansURLOverride,
@@ -169,7 +175,7 @@ func NewHarvester(options ...func(*Config)) (*Harvester, error) {
 	return h, nil
 }
 
-func sanitizeAPIKeyForLogging(apiKey string) string {
+func sanitizeKeyForLogging(apiKey string) string {
 	if len(apiKey) <= 8 {
 		return apiKey
 	}
diff --git a/telemetry/harvester_test.go b/telemetry/harvester_test.go
index 6a599ff..9cba12c 100644
--- a/telemetry/harvester_test.go
+++ b/telemetry/harvester_test.go
@@ -135,11 +135,11 @@ func TestSanitizeApiKeyForLogging(t *testing.T) {
 			t.Errorf("Got %s but expected %s", actual, expected)
 		}
 	}
-	assertEqual("", sanitizeAPIKeyForLogging(""))
-	assertEqual("", sanitizeAPIKeyForLogging(""))
-	assertEqual("foo", sanitizeAPIKeyForLogging("foo"))
-	assertEqual("foobarba", sanitizeAPIKeyForLogging("foobarbazqux"))
-	assertEqual("eu01xxfoobarba", sanitizeAPIKeyForLogging("eu01xxfoobarbazqux"))
+	assertEqual("", sanitizeKeyForLogging(""))
+	assertEqual("", sanitizeKeyForLogging(""))
+	assertEqual("foo", sanitizeKeyForLogging("foo"))
+	assertEqual("foobarba", sanitizeKeyForLogging("foobarbazqux"))
+	assertEqual("eu01xxfoobarba", sanitizeKeyForLogging("eu01xxfoobarbazqux"))
 }
 
 func TestHarvesterRecordSpan(t *testing.T) {

Unfortunately I'm still seeing 403s when posting my custom metrics:

package main

import (
	"context"
	"flag"
	"fmt"
	"io"
	"log"
	"math/rand"
	"net/http"
	"os"
	"strconv"
	"time"

	"github.com/newrelic/go-agent/v3/newrelic"
	"github.com/newrelic/newrelic-telemetry-sdk-go/telemetry"
)

func getPortFromEnvOrDefault(defaultValue int) (int, error) {
	s, present := os.LookupEnv("PORT")
	if present {
		return strconv.Atoi(s)
	}
	return defaultValue, nil
}

const newRelicLicenseKey = "eu01x...."

func main() {
	app, err := newrelic.NewApplication(
		newrelic.ConfigAppName("Example"),
		newrelic.ConfigLicense(newRelicLicenseKey),
		newrelic.ConfigDistributedTracerEnabled(true),
	)
	if err != nil {
		log.Fatalf("cannot initialize NewRelic, %v", err)
	}

	defaultPort, err := getPortFromEnvOrDefault(8080)
	if err != nil {
		log.Fatalf("\"PORT\" environment variable has invalid value, %v", err)
	}
	port := flag.Int("port", defaultPort, "Port")
	flag.Parse()

	// Configure the harvester
	// First create a Harvester.  APIKey is the only required field.
	h, err := telemetry.NewHarvester(
		telemetry.ConfigLicenseKey(newRelicLicenseKey),
		telemetry.ConfigBasicDebugLogger(os.Stdout),
		telemetry.ConfigBasicErrorLogger(os.Stdout))
	if err != nil {
		log.Fatalf("cannot initialize NewRelic Harvester, %v", err)
	}

	done := make(chan bool)
	ticker := time.NewTicker(10 * time.Second)
	defer func() {
		done <- true
	}()

	go func() {
		for {

			select {
			case <-done:
				ticker.Stop()
				return
			case <-ticker.C:
				value := rand.Intn(5)
				log.Printf("reporting metric value %d", value)
				h.RecordMetric(telemetry.Gauge{
					Timestamp: time.Now(),
					Value:     float64(value),
					Name:      "myMetric",
				})
				aggregator := h.MetricAggregator()
				m := aggregator.Gauge("myAggregatedMetric", map[string]interface{}{})
				m.Value(float64(value))
				h.HarvestNow(context.TODO())
			}
		}
	}()

	helloHandler := func(w http.ResponseWriter, req *http.Request) {
		io.WriteString(w, "Hello, world!\n")
	}

	http.HandleFunc(newrelic.WrapHandleFunc(app, "/hello", helloHandler))

	log.Println(fmt.Sprintf("Listing for requests at http://localhost:%d/hello", *port))
	addr := fmt.Sprintf(":%d", *port)
	log.Fatal(http.ListenAndServe(addr, nil))
}

[ankon]

Unfortunately I'm still seeing 403s when posting my custom metrics:

Resolved when setting the metrics URL to the "eu" endpoint. Will create a PR for supporting the license key based on the posted diff above.