fix reported issues

changelog.d/add-user-labels-to-gcp-stackdriver-logs-sink.enhancement.md

@@ -1,4 +1,17 @@
-Add support for labels with gcp_stackdriver_logs config
-Add support for labels from structured logs matching key specified via `labels_key` gcp_stackdriver_logs config
+Add support for static labels in gcp_stackdriver_logs sink.
+
+    This enhancement enables users to define static labels directly in the
+    gcp_stackdriver_logs sink configuration. Static labels are key-value pairs
+    that are consistently applied to all log entries sent to Google Cloud Logging,
+    improving log organization and filtering capabilities.
+
+
+Add support for dynamic labels in gcp_stackdriver_logs sink via `labels_key`.
+
+    This enhancement allows Vector to automatically map fields from structured
+    log entries to Google Cloud LogEntry labels. When a structured log contains
+    fields matching the configured `labels_key`, Vector will populate the
+    corresponding labels in the Google Cloud LogEntry, enabling better log
+    organization and filtering in Google Cloud Logging.
 
 authors: stackempty

src/sinks/gcp/stackdriver/logs/config.rs

@@ -168,7 +168,7 @@ pub(super) struct StackdriverLabelConfig {
     /// and extract their values to set as LogEntry labels.
     #[configurable(metadata(docs::examples = "logging.googleapis.com/labels"))]
     #[serde(default = "default_labels_key")]
-    pub(super) labels_key: String,
+    pub(super) labels_key: Option<String>,
 
     /// A map of key, value pairs that provides additional information about the log entry.
     #[configurable(metadata(
@@ -186,8 +186,8 @@ fn labels_examples() -> HashMap<String, String> {
     example
 }
 
-fn default_labels_key() -> String {
-    "logging.googleapis.com/labels".to_string()
+fn default_labels_key() -> Option<String> {
+    Some("logging.googleapis.com/labels".to_string())
 }
 
 /// A monitored resource.

src/sinks/gcp/stackdriver/logs/encoder.rs

@@ -93,15 +93,20 @@ impl StackdriverLogsEncoder {
             .map(remap_severity)
             .unwrap_or_else(|| 0.into());
 
+        let labels_key = self
+            .label_config
+            .labels_key
+            .as_ref()
+            .map(|s| s.as_str())
+            .unwrap_or_else(|| "logging.googleapis.com/labels".into());
+
         // merge log_labels in the specified labels_key into the labels map.
-        if let Some(log_labels) = log.remove(event_path!(self.label_config.labels_key.as_str())) {
-            if let Value::Object(log_labels) = log_labels {
-                labels.extend(
-                    log_labels
-                        .into_iter()
-                        .map(|(k, v)| (k.to_string(), v.to_string_lossy().into_owned())),
-                );
-            }
+        if let Some(Value::Object(log_labels)) = log.remove(event_path!(labels_key)) {
+            labels.extend(
+                log_labels
+                    .into_iter()
+                    .map(|(k, v)| (k.to_string(), v.to_string_lossy().into_owned())),
+            );
         }
 
         let mut event = Event::Log(log);

src/sinks/gcp/stackdriver/logs/tests.rs

@@ -79,7 +79,7 @@ fn encode_valid() {
         Template::try_from("{{ log_id }}").unwrap(),
         StackdriverLogName::Project("project".to_owned()),
         StackdriverLabelConfig {
-            labels_key: "logging.googleapis.com/labels".to_owned(),
+            labels_key: Some("logging.googleapis.com/labels".to_owned()),
             labels: HashMap::from([(
                 "config_user_label_1".to_owned(),
                 Template::try_from("config_user_value_1").unwrap(),
@@ -143,7 +143,7 @@ fn encode_inserts_timestamp() {
         Template::try_from("testlogs").unwrap(),
         StackdriverLogName::Project("project".to_owned()),
         StackdriverLabelConfig {
-            labels_key: "user_label_key".to_owned(),
+            labels_key: Some("user_label_key".to_owned()),
             labels: HashMap::from([(
                 "config_user_label_1".to_owned(),
                 Template::try_from("value_1").unwrap(),
@@ -225,7 +225,7 @@ async fn correct_request() {
         Template::try_from("testlogs").unwrap(),
         StackdriverLogName::Project("project".to_owned()),
         StackdriverLabelConfig {
-            labels_key: "user_label_key".to_owned(),
+            labels_key: Some("user_label_key".to_owned()),
             labels: HashMap::from([(
                 "config_user_label_1".to_owned(),
                 Template::try_from("value_1").unwrap(),