App Configuration with OCI Centralized Configuration Providers in node-oracledb

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Centralized Configuration Providers provide centralized storage and management of your database and application’s configuration information on Oracle Cloud Infrastructure (OCI).

Recently, I had published a detailed blog on Using OCI Centralized Configuration Providers for Oracle Database applications, which focuses on database configuration management.
We can also manage application-specific configuration on OCI. From node-oracledb 6.6 onwards, you can fetch properties specific to node-oracledb in Centralized Configuration Providers.

In this short blog, I will take you through the steps of creating a sample solution to fetch node-oracledb specific properties from Centralized Configuration Providers. I will use the Oracle Cloud setup that is detailed in my OCI Centralized Configuration Providers blog.

Create OCI Storage JSON File

{
  "connect_descriptor": "localhost/orclpdb",
  "user": "user1",
  "password": "password1",
  "node-oracledb": {
    "poolMin": 2,
    "poolMax": 5,
    "poolIncrement": 2,
    "poolTimeout": 39,
    "poolPingInterval": 15,
    "poolPingTimeout": 50,
    "stmtCacheSize": 1000,
    "prefetchRows": 10
 }
}

Save this file (say oracledbConfig) in an OCI Bucket (say testBucket).

The node-oracledb specific properties are available as part of the node-oracledb sub-object. The connect_descriptor property for the database connect string is mandatory and should provided at a minimum.

Bucket page

Get the Object URL of this file.

Object URL

These steps are detailed in my OCI Centralized Configuration Providers blog.

Create and Run Node.js App

'use strict';
Error.stackTraceLimit = 50;
const oracledb = require('oracledb');

async function run() {
  // Replace the connect string with correct OCI Config Store URL
  // Replace xxxx in the connect string with the correct authentication parameter values
  let pool, connection;
  const options = {
    // Replace the connect string here with URL of the 'oracledbConfig' file
    // config-ociobject://<object_store_server_name>/n/{namespace}/b/{bucketname}/o/{filename}[/c/{network_service_name_or_alias}][?option1=value1&option2=value2...]
    connectString: 'config-ociobject://objectstorage.region.oraclecloud.com/n/testNamespace/b/testBucket/o/oracledbConfig',
  };
  try {
    // Create a pool and get a connection from the pool
    pool = await oracledb.createPool(options);
    console.log('Pool Created Successfully');

    // List the pool parameters fetched from the OCI Config Store!
    console.log('pool.stmtCacheSize:', pool.stmtCacheSize);
    console.log('pool.poolMin:', pool.poolMin);
    console.log('pool.poolMax', pool.poolMax);
    console.log('pool.poolIncrement:', pool.poolIncrement);
    console.log('pool.poolTimeout:', pool.poolTimeout);
    console.log('pool.poolPingInterval:', pool.poolPingInterval);
    console.log('pool.poolPingTimeout:', pool.poolPingTimeout);

    // Create a connection from the pool
    connection = await pool.getConnection();
    console.log('\nCreated connection from the pool successfully!');

  } catch (err) {
    console.error(err);
  } finally {
    if (connection) {
      try {
        await connection.close();
      } catch (err) {
        console.error(err);
      }
    }

    if (pool) {
      try {
        await pool.close();
      } catch (err) {
        console.error(err);
      }
    }
  }
}

run();

This program creates an application-side connection pool with the pool parameters set from the OCI Centralized Configuration Providers.

This program gives the following output:

Pool Created Successfully
pool.stmtCacheSize: 1000
pool.poolMin: 2
pool.poolMax 5
pool.poolIncrement: 2
pool.poolTimeout: 39
pool.poolPingInterval: 15
pool.poolPingTimeout: 50

Created connection from the pool successfully!

As shown above, the application pool picks up all the node-oracledb parameters from the OCI Centralized Configuration Providers.

This provides the advantage of a standardized and centralized configuration setting for all the applications that use node-oracledb. The individual application developer does not need to worry about sizing the pool or cache of the application as the application.

Happy coding!