condition check lambda

lambdas/shared/db/connection.js

@@ -0,0 +1,89 @@
+const { Pool } = require("pg");
+
+let pool = null;
+
+/**
+ * Get or create a PostgreSQL connection pool.
+ * Uses connection pooling optimized for Lambda:
+ * - Reuses connections across invocations (when container is warm)
+ * - Small pool size to avoid exhausting database connections
+ *
+ * Expects DATABASE_URL environment variable in format:
+ * postgresql://user:password@host:port/database
+ */
+function getPool() {
+  if (!pool) {
+    const connectionString = process.env.DATABASE_URL;
+
+    if (!connectionString) {
+      throw new Error("DATABASE_URL environment variable is required");
+    }
+
+    pool = new Pool({
+      connectionString,
+      // Lambda-optimized settings
+      max: 1, // Single connection per Lambda instance
+      idleTimeoutMillis: 120000, // 2 minutes - keep connection warm
+      connectionTimeoutMillis: 5000, // 5 seconds to connect
+    });
+
+    // Handle pool errors
+    pool.on("error", (err) => {
+      console.error("Unexpected database pool error:", err);
+      pool = null; // Reset pool on error
+    });
+  }
+
+  return pool;
+}
+
+/**
+ * Execute a query with automatic connection management.
+ * @param {string} text - SQL query text
+ * @param {Array} params - Query parameters
+ * @returns {Promise<object>} Query result
+ */
+async function query(text, params) {
+  const pool = getPool();
+  const start = Date.now();
+
+  try {
+    const result = await pool.query(text, params);
+    const duration = Date.now() - start;
+
+    console.log(JSON.stringify({
+      level: "debug",
+      message: "Executed query",
+      query: text.substring(0, 100),
+      duration,
+      rows: result.rowCount,
+    }));
+
+    return result;
+  } catch (error) {
+    console.error(JSON.stringify({
+      level: "error",
+      message: "Query failed",
+      query: text.substring(0, 100),
+      error: error.message,
+    }));
+    throw error;
+  }
+}
+
+/**
+ * Close the connection pool (for cleanup).
+ * Call this at the end of Lambda execution if needed.
+ */
+async function closePool() {
+  if (pool) {
+    await pool.end();
+    pool = null;
+  }
+}
+
+module.exports = {
+  getPool,
+  query,
+  closePool,
+};