Merge pull request #103 from AndrewChubatiuk/allow-override-placeholders

allow override placeholders

config.go

@@ -17,6 +17,13 @@ import (
 	"gopkg.in/yaml.v2"
 )
 
+func getenv(key, defaultVal string) string {
+	if val, found := os.LookupEnv(key); found {
+		return val
+	}
+	return defaultVal
+}
+
 var (
 	failedScrapes = prometheus.NewGaugeVec(
 		prometheus.GaugeOpts{
@@ -25,7 +32,9 @@ var (
 		},
 		[]string{"driver", "host", "database", "user", "sql_job", "query"},
 	)
-	reEnvironmentPlaceholders = regexp.MustCompile(`{{.+?}}`)
+	tmplStart                 = getenv("TEMPLATE_START", "{{")
+	tmplEnd                   = getenv("TEMPLATE_END", "}}")
+	reEnvironmentPlaceholders = regexp.MustCompile(fmt.Sprintf("%s.+?%s", tmplStart, tmplEnd))
 )
 
 func init() {
@@ -49,10 +58,12 @@ func Read(path string) (File, error) {
 	}
 
 	placeholders := reEnvironmentPlaceholders.FindAllString(string(buf), -1)
-	replacer := strings.NewReplacer("{{", "", "}}", "")
+	replacer := strings.NewReplacer(tmplStart, "", tmplEnd, "")
 	var replacements []string
 	for _, placeholder := range placeholders {
-		environmentVariableName := strings.ToUpper(replacer.Replace(placeholder))
+		environmentVariableName := strings.TrimSpace(
+			strings.ToUpper(replacer.Replace(placeholder)),
+		)
 		environmentVariableValue := os.Getenv(environmentVariableName)
 
 		// We extracted a placeholder and found the value in the env variables to replace it with

examples/kubernetes/configmap.yml

@@ -227,6 +227,7 @@ data:
       - 'postgres://postgres_exporter@postgres/db1?sslmode=disable'
       - 'postgres://postgres_exporter@postgres/db2?sslmode=disable'
       - 'postgres://postgres_exporter@postgres/db3?sslmode=disable'
+      - '[[ POSTGRES_CONNECTION_DB4 ]]'
       queries:
       - name: "pg_stat_user_tables"
         help: "Table stats"

examples/kubernetes/deployment.yml

@@ -26,6 +26,12 @@ spec:
           value: /config/config.yml
         - name: PGPASSFILE
           value: /pgpass/pgpass
+        - name: TEMPLATE_START
+          value: '[['
+        - name: TEMPLATE_END
+          value: ']]'
+        - name: POSTGRES_CONNECTION_DB4
+          value: postgres://postgres_exporter@postgres/db4?sslmode=disable
         image: ghcr.io/justwatchcom/sql_exporter:latest
         livenessProbe:
           httpGet: