feat: No longer launch Go-based agent for compatibility/OTLP/AAP config

bottlecap/src/bin/bottlecap/main.rs

@@ -37,6 +37,7 @@ use bottlecap::{
     },
     logger,
     logs::{agent::LogsAgent, flusher::LogsFlusher},
+    metrics::enhanced::lambda::Lambda as enhanced_metrics,
     otlp::{agent::Agent as OtlpAgent, should_enable_otlp_agent},
     proxy::{interceptor, should_start_proxy},
     secrets::decrypt,
@@ -84,9 +85,7 @@ use std::{
     collections::{HashMap, hash_map},
     env,
     io::{Error, Result},
-    os::unix::process::CommandExt,
     path::Path,
-    process::Command,
     sync::{Arc, Mutex},
     time::{Duration, Instant},
 };
@@ -402,14 +401,7 @@ fn load_configs(start_time: Instant) -> (AwsConfig, AwsCredentials, Arc<Config>)
     let aws_credentials = AwsCredentials::from_env();
     let lambda_directory: String =
         env::var("LAMBDA_TASK_ROOT").unwrap_or_else(|_| "/var/task".to_string());
-    let config = match config::get_config(Path::new(&lambda_directory)) {
-        Ok(config) => Arc::new(config),
-        Err(_e) => {
-            let err = Command::new("/opt/datadog-agent-go").exec();
-            panic!("Error starting the extension: {err:?}");
-        }
-    };
-
+    let config = Arc::new(config::get_config(Path::new(&lambda_directory)));
     (aws_config, aws_credentials, config)
 }
 
@@ -508,12 +500,22 @@ async fn extension_loop_active(
             .as_micros()
             .to_string()
     );
-
+    let metrics_intake_url = create_metrics_intake_url_prefix(config);
     let metrics_flushers = Arc::new(TokioMutex::new(start_metrics_flushers(
         Arc::clone(&api_key_factory),
         &metrics_aggr,
+        &metrics_intake_url,
         config,
     )));
+
+    // Create lambda enhanced metrics instance once
+    let lambda_enhanced_metrics =
+        enhanced_metrics::new(Arc::clone(&metrics_aggr), Arc::clone(config));
+
+    // Send config issue metrics
+    let config_issues = config::fallback(config);
+    send_config_issue_metric(&config_issues, &lambda_enhanced_metrics);
+
     // Lifecycle Invocation Processor
     let invocation_processor = Arc::new(TokioMutex::new(InvocationProcessor::new(
         Arc::clone(&tags_provider),
@@ -1006,33 +1008,33 @@ fn start_logs_agent(
     (logs_agent_channel, logs_flusher)
 }
 
-fn start_metrics_flushers(
-    api_key_factory: Arc<ApiKeyFactory>,
-    metrics_aggr: &Arc<Mutex<MetricsAggregator>>,
-    config: &Arc<Config>,
-) -> Vec<MetricsFlusher> {
-    let mut flushers = Vec::new();
-
-    let metrics_intake_url = if !config.dd_url.is_empty() {
+fn create_metrics_intake_url_prefix(config: &Config) -> MetricsIntakeUrlPrefix {
+    if !config.dd_url.is_empty() {
         let dd_dd_url = DdDdUrl::new(config.dd_url.clone()).expect("can't parse DD_DD_URL");
-
         let prefix_override = MetricsIntakeUrlPrefixOverride::maybe_new(None, Some(dd_dd_url));
-        MetricsIntakeUrlPrefix::new(None, prefix_override)
+        MetricsIntakeUrlPrefix::new(None, prefix_override).expect("can't parse DD_DD_URL prefix")
     } else if !config.url.is_empty() {
         let dd_url = DdUrl::new(config.url.clone()).expect("can't parse DD_URL");
-
         let prefix_override = MetricsIntakeUrlPrefixOverride::maybe_new(Some(dd_url), None);
-        MetricsIntakeUrlPrefix::new(None, prefix_override)
+        MetricsIntakeUrlPrefix::new(None, prefix_override).expect("can't parse DD_URL prefix")
     } else {
-        // use site
         let metrics_site = MetricsSite::new(config.site.clone()).expect("can't parse site");
-        MetricsIntakeUrlPrefix::new(Some(metrics_site), None)
-    };
+        MetricsIntakeUrlPrefix::new(Some(metrics_site), None).expect("can't parse site prefix")
+    }
+}
+
+fn start_metrics_flushers(
+    api_key_factory: Arc<ApiKeyFactory>,
+    metrics_aggr: &Arc<Mutex<MetricsAggregator>>,
+    metrics_intake_url: &MetricsIntakeUrlPrefix,
+    config: &Arc<Config>,
+) -> Vec<MetricsFlusher> {
+    let mut flushers = Vec::new();
 
     let flusher_config = MetricsFlusherConfig {
         api_key_factory,
         aggregator: Arc::clone(metrics_aggr),
-        metrics_intake_url_prefix: metrics_intake_url.expect("can't parse site or override"),
+        metrics_intake_url_prefix: metrics_intake_url.clone(),
         https_proxy: config.proxy_https.clone(),
         timeout: Duration::from_secs(config.flush_timeout),
         retry_strategy: DsdRetryStrategy::Immediate(3),
@@ -1157,6 +1159,28 @@ fn start_trace_agent(
     )
 }
 
+/// Sends metrics indicating issue with configuration.
+///
+/// # Arguments
+/// * `issue_reasons` - Vector of messages describing the issue with the configurations
+/// * `lambda_enhanced_metrics` - The lambda enhanced metrics instance
+fn send_config_issue_metric(issue_reasons: &[String], lambda_enhanced_metrics: &enhanced_metrics) {
+    if issue_reasons.is_empty() {
+        return;
+    }
+    let now = std::time::UNIX_EPOCH
+        .elapsed()
+        .expect("can't poll clock")
+        .as_secs()
+        .try_into()
+        .unwrap_or_default();
+
+    // Setup a separate metric for each config issue reason
+    for issue_reason in issue_reasons {
+        lambda_enhanced_metrics.set_config_load_issue_metric(now, issue_reason);
+    }
+}
+
 async fn start_dogstatsd(metrics_aggr: &Arc<Mutex<MetricsAggregator>>) -> CancellationToken {
     let dogstatsd_config = DogStatsDConfig {
         host: EXTENSION_HOST.to_string(),