Updated deobfuscation logic for pool credentials to improve performance

Author: sharadraju

lib/thin/pool.js

@@ -144,13 +144,13 @@ class ThinPoolImpl extends PoolImpl {
   }
 
   //---------------------------------------------------------------------------
-  // get connection from pool
+  // credentials are obfuscated and stored in an object(userConfig) during
+  // pool creation. _getConnAttrs() method is used to deobfuscate encrypted
+  // credentials for creating new connections
   //---------------------------------------------------------------------------
-  async _connect(connAttrs) {
+  async _getConnAttrs() {
     let accessToken;
-    const conn = new ThinConnectionImpl();
-    conn._pool = this;
-    let clonedAttrs = Object.assign({}, connAttrs);
+    const clonedAttrs = Object.assign({}, this._userConfig);
     if (clonedAttrs.password === null) {
       clonedAttrs.password = protocolUtil.getDeobfuscatedValue(this._password,
         this._obfuscatedPassword);
@@ -204,9 +204,7 @@ class ThinPoolImpl extends PoolImpl {
         protocolUtil.getDeobfuscatedValue(this._privateKey,
           this._obfuscatedPrivateKey);
     }
-    await conn.connect(clonedAttrs);
-    clonedAttrs = null;
-    return conn;
+    return clonedAttrs;
   }
 
   //---------------------------------------------------------------------------
@@ -318,8 +316,11 @@ class ThinPoolImpl extends PoolImpl {
   // Grows the pool to include the specified number of connections.
   //---------------------------------------------------------------------------
   async _growPool(numConns) {
+    const clonedAttrs = await this._getConnAttrs();
     while (numConns > 0) {
-      let conn = await this._connect(this._userConfig);
+      const conn = new ThinConnectionImpl();
+      conn._pool = this;
+      await conn.connect(clonedAttrs);
       conn._newSession = true;
       conn._dropSess = false;
       conn._lastTimeUsed = Date.now();