refactor: modularize codebase and add 404 unit tests (#13)

compliance-agent/src/api/handlers/health.rs

@@ -0,0 +1,84 @@
+use axum::Json;
+use mongodb::bson::doc;
+
+use super::dto::*;
+use compliance_core::models::ScanRun;
+
+#[tracing::instrument(skip_all)]
+pub async fn health() -> Json<serde_json::Value> {
+    Json(serde_json::json!({ "status": "ok" }))
+}
+
+#[tracing::instrument(skip_all)]
+pub async fn stats_overview(axum::extract::Extension(agent): AgentExt) -> ApiResult<OverviewStats> {
+    let db = &agent.db;
+
+    let total_repositories = db
+        .repositories()
+        .count_documents(doc! {})
+        .await
+        .unwrap_or(0);
+    let total_findings = db.findings().count_documents(doc! {}).await.unwrap_or(0);
+    let critical_findings = db
+        .findings()
+        .count_documents(doc! { "severity": "critical" })
+        .await
+        .unwrap_or(0);
+    let high_findings = db
+        .findings()
+        .count_documents(doc! { "severity": "high" })
+        .await
+        .unwrap_or(0);
+    let medium_findings = db
+        .findings()
+        .count_documents(doc! { "severity": "medium" })
+        .await
+        .unwrap_or(0);
+    let low_findings = db
+        .findings()
+        .count_documents(doc! { "severity": "low" })
+        .await
+        .unwrap_or(0);
+    let total_sbom_entries = db
+        .sbom_entries()
+        .count_documents(doc! {})
+        .await
+        .unwrap_or(0);
+    let total_cve_alerts = db.cve_alerts().count_documents(doc! {}).await.unwrap_or(0);
+    let total_issues = db
+        .tracker_issues()
+        .count_documents(doc! {})
+        .await
+        .unwrap_or(0);
+
+    let recent_scans: Vec<ScanRun> = match db
+        .scan_runs()
+        .find(doc! {})
+        .sort(doc! { "started_at": -1 })
+        .limit(10)
+        .await
+    {
+        Ok(cursor) => collect_cursor_async(cursor).await,
+        Err(e) => {
+            tracing::warn!("Failed to fetch recent scans: {e}");
+            Vec::new()
+        }
+    };
+
+    Ok(Json(ApiResponse {
+        data: OverviewStats {
+            total_repositories,
+            total_findings,
+            critical_findings,
+            high_findings,
+            medium_findings,
+            low_findings,
+            total_sbom_entries,
+            total_cve_alerts,
+            total_issues,
+            recent_scans,
+        },
+        total: None,
+        page: None,
+    }))
+}