add pools for oracle

Author: Sylvestre Gug

lib/oracle.js

@@ -4,6 +4,7 @@ import {Transform} from "stream";
 
 import {badRequest, failedCheck} from "./errors.js";
 import {validateQueryPayload} from "./validate.js";
+import Pools from "./pools.js";
 
 const READ_ONLY = new Set(["SELECT", "USAGE", "CONNECT"]);
 export class OracleSingleton {
@@ -217,6 +218,23 @@ export async function check(req, res, pool) {
   }
 }
 
+export const pools = new Pools(async (credentials) => {
+  const oracledb = await OracleSingleton.getInstance();
+  credentials.connectionString = decodeURI(credentials.connectionString);
+  const pool = await oracledb.createPool(credentials);
+
+  Object.defineProperty(pool, "end", {
+    value() {
+      // We must ensure there is no query still running before we close the pool.
+      if (this._connectionsOut === 0) {
+        this.close();
+      }
+    },
+  });
+
+  return pool;
+});
+
 export default async ({url, username, password}) => {
   OracleSingleton.initialize();
   // We do not want to import the oracledb library until we are sure that the user is looking to use Oracle.