Add dd service tag (#920)

Author: eversC

examples/README.md

@@ -11,7 +11,7 @@ If running in AWS Lambda, store the config in SecretManager in a secret named
 `ckr-config`.
 
 If running in GCP CloudFunctions, store the config in GCS, e.g. in
-`your_bucket/ckr-config.json`, then set an env var 
+`your_bucket/ckr-config.json`, then set an env var
 `CKR_BUCKET_NAME=your_bucket`.
 
 Otherwise, when running the binary or code directly, pop the config into
@@ -22,27 +22,29 @@ a file called `config.json` in `/etc/cloud-key-rotator/`.
 For scraping of AWS key ages:
 
 ```json
-
 {
   "EnableKeyAgeLogging": true,
   "RotationMode": false,
-  "CloudProviders": [{
-    "Name":"aws"
-  }]
+  "CloudProviders": [
+    {
+      "Name": "aws"
+    }
+  ]
 }
 ```
 
 For scraping of GCP key ages:
 
 ```json
-
 {
   "EnableKeyAgeLogging": true,
   "RotationMode": false,
-  "CloudProviders": [{
-    "Project":"my-project",
-    "Name": "gcp"
-  }]
+  "CloudProviders": [
+    {
+      "Project": "my-project",
+      "Name": "gcp"
+    }
+  ]
 }
 ```
 
@@ -55,6 +57,7 @@ If you add a Datadog struct to the config, you can get `cloud-key-rotator` to po
     "MetricEnv": "prod",
     "MetricName": "cloud-key-rotator.age",
     "MetricProject": "my_project",
+    "MetricService": "my_service",
     "MetricTeam": "my_team"
   },
   "DatadogAPIKey": "okj23434poz3j4o324p455oz3j4o324",

pkg/config/config.go

@@ -58,6 +58,7 @@ type Datadog struct {
 	MetricTeam    string
 	MetricName    string
 	MetricProject string
+	MetricService string
 }
 
 // Filter type

pkg/rotate/rotatekeys.go

@@ -537,6 +537,12 @@ func isDatadogKeySet(apiKey string) bool {
 // postMetric posts details of each keys.Key to a metrics api
 func postMetric(keys []keys.Key, apiKey string, datadog config.Datadog) (err error) {
 	url := strings.Join([]string{datadogURL, apiKey}, "")
+	ddServiceTag := "cloud-key-rotator"
+	if datadog.MetricService != "" {
+		ddServiceTag = datadog.MetricService
+	} else if datadog.MetricProject != "" {
+		ddServiceTag = datadog.MetricProject
+	}
 	for _, key := range keys {
 		var jsonString = []byte(
 			`{ "series" :[{"metric":"` + datadog.MetricName + `",` +
@@ -548,6 +554,7 @@ func postMetric(keys []keys.Key, apiKey string, datadog config.Datadog) (err err
 				`"tags":[` +
 				`"team:` + datadog.MetricTeam + `",` +
 				`"project:` + datadog.MetricProject + `",` +
+				`"service:` + ddServiceTag + `",` +
 				`"environment:` + datadog.MetricEnv + `",` +
 				`"key:` + key.Name + `",` +
 				`"provider:` + key.Provider.Provider + `",` +