How to use nodejs configuration parameters

Node.js is a JavaScript runtime built on the Chrome V8 engine, which allows JavaScript to run on the server side. Node.js is scalable and flexible, and its behavior can be customized through configuration parameters.

Configuration parameters for Node.js can be passed as command line options when starting the application, or they can be accessed in scripts using the process object. This article will introduce how to use Node.js configuration parameters to optimize the performance and reliability of your application.

1. Port number

When deploying a Node.js application, you must choose a port number. By default, Node.js uses port 3000, but if you need to change it to a different port number, you can use the following command:

node index.js --port=8080

This will make the Node.js application listen for requests on port 8080.

2. Environment Variables

Node.js applications can run in multiple environments, such as development, testing, production, etc. You can use environment variables to distinguish different environments and load different configuration files based on the value of the environment variable. The following is an example of how to set environment variables:

In Linux systems, you can use the export command to set environment variables:

export NODE_ENV=production

In Windows systems, you can use the set command to set environment variables:

set NODE_ENV=production

In Node.js code, you can use the following command to get the value of the environment variable:

const env = process.env.NODE_ENV || 'development';

If the NODE_ENV environment variable is not set, the development environment is used by default.

3. Log level

Log is an important debugging tool in the application, which can help developers quickly locate problems. Node.js records the status of the application by using different log levels, such as debug, info, warn, error, etc. The log level can be set to debug using the following command:

node index.js --log-level=debug

This will cause the Node.js application to log all types of log information.

4. Memory Limitation

Node.js requires a lot of memory when processing large data and files. The memory limit can be set for a Node.js application using the following command:

node --max-old-space-size=4096 index.js

This will allocate 4GB of memory for the Node.js application.

5. HTTPS

HTTPS is a secure HTTP protocol that encrypts data. Node.js applications can be configured to support HTTPS using the following command:

const https = require('https');
const fs = require('fs');

const options = {
  key: fs.readFileSync('/path/to/your/key.pem'),
  cert: fs.readFileSync('/path/to/your/cert.pem')
};

https.createServer(options, function (req, res) {
  res.writeHead(200);
  res.end('hello world
');
}).listen(443);

In the above code, the certificate file should be issued by a trusted certificate authority.

6. Other parameters

In addition to the above parameters, there are other parameters that can be used, such as:

• --inspect: enable debugging device.
• --trace-uncaught: Generate a stack trace when an uncaught exception occurs.
• --no-deprecation: Disable the generation of warning messages when deprecated APIs are used.
• --trace-deprecation: Generate stack traces when using deprecated APIs.
• --prof: Generate performance analysis report.

Summary

In Node.js, there are many configuration parameters available that can help developers optimize the performance and reliability of their applications. When writing Node.js applications, you should use different configuration parameters as needed and follow best practices to ensure maximum application performance.

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