pkg/operator/config: don't set non-existent username_file field

CHANGELOG.md

@@ -37,6 +37,9 @@ Main (unreleased)
 - Set the `Content-Type` HTTP header to `application/json` for API endpoints
   returning json objects. (@marctc)
 
+- Operator: fix issue where a `username_file` field was incorrectly set.
+  (@rfratto)
+
 ### Other changes
 
 - Update base image of official Docker containers from Debian buster to Debian

pkg/operator/config/config_test.go

@@ -80,7 +80,7 @@ func TestBuildConfigMetrics(t *testing.T) {
 								basicAuth:
 									username:
 										name: example-secret
-										key: uname
+										key: key
 									password:
 										name: example-secret
 										key: pword
@@ -113,7 +113,7 @@ func TestBuildConfigMetrics(t *testing.T) {
 							remote_write:
 							- url: http://localhost:9090/api/v1/write
 								basic_auth:
-									username_file: /var/lib/grafana-agent/secrets/_secrets_default_example_secret_uname
+									username: somesecret
 									password_file: /var/lib/grafana-agent/secrets/_secrets_default_example_secret_pword
 								tls_config:
 									ca_file: /var/lib/grafana-agent/secrets/_configMaps_default_example_cm_key

pkg/operator/config/metrics_templates_test.go

@@ -568,7 +568,7 @@ func TestRemoteWrite(t *testing.T) {
 			expect: util.Untab(`
 				url: http://cortex/api/prom/push
 				basic_auth:
-					username_file: /var/lib/grafana-agent/secrets/_secrets_operator_obj_key
+					username: secretkey
 					password_file: /var/lib/grafana-agent/secrets/_secrets_operator_obj_key
 			`),
 		},

pkg/operator/config/templates/component/metrics/remote_write.libsonnet

@@ -30,7 +30,7 @@ function(namespace, rw) {
 
   basic_auth: (
     if rw.BasicAuth != null then {
-      username_file: secrets.pathForSecret(namespace, rw.BasicAuth.Username),
+      username: secrets.valueForSecret(namespace, rw.BasicAuth.Username),
       password_file: secrets.pathForSecret(namespace, rw.BasicAuth.Password),
     }
   ),