My own preparation for NodeJS Certification
🎓 This repository contains examples that I have done for my own preparation for the NodeJS certification exam - Application Developer (JSNAD).
This content is not official from the OpenJS Foundation or from NodeJS.
🔖 Description
I have been working in this repository for several months. I have wanted to share OpenSource examples that I have developed for my own preparation. These examples are organized by folders for each NodeJS API.
📖 Temary
Usage & Example
Assertion Testing
Buffer
Child Processes
Cluster
Console
ECMAScript Modules
Errors
Events
File System
HTTP
HTTP/2
HTTPS
Inspector
Internationalization
Modules
Net
OS
Path
Performance Hooks
Process
Query Strings
Readline
REPL
Report
Stream
Timers
Utilities
V8
VM
Worker Threads
Zlib
💪 JSNAD Domains & Competencies
- Buffer and Streams – 11%
- Node.js Buffer API’s
- Incremental Processing
- Transforming Data
- Connecting Streams
- Control flow – 12%
- Managing asynchronous operations
- Control flow abstractions
- Child Processes – 8%
- Spawning or Executing child processes
- Child process configuration
- Diagnostics – 6%
- Debugging Node.js
- Basic performance analysis
- Error Handling – 8%
- Common patterns
- Handling errors in various scenarios
- Node.js CLI – 4%
- Node executable command line flags
- Events – 11%
- The event system
- Building event emitters
- Consuming event emitters
- File System – 8%
- Input/output
- Watching
- JavaScript Prerequisites – 7%
- Language fundamentals
- Scoped to core language features introduced since EcmaScript 1 and still heavily used today
- Module system – 7%
- CommonJS Module System only
- Process/Operating System – 6%
- Controlling the process
- Getting system data
- Package.json – 6%
- Package configuration
- Dependency management
- Unit Testing – 6%
- Using assertions
- Testing synchronous code
- Testing asynchronous code
🌍 Websites of Interest
-
Generic
-
Child Processes
-
Console
-
ECMAScript Modules
-
Events
-
File System
-
Worker Threads
-
Control Flow
-
Performance Hooks
-
Stream
- Backpressuring in Streams
- Understanding Streams in Node.js
- Node.js Streams Tutorial - An Introduction to Node.js Streams
- Node.js Stream Tutorial - The Power and Simplicity of Node.js Streams
- El manejo de streams en NodeJS
- Node.js Streams: Everything you need to know
- Using Node.js to Read Really, Really Large Datasets & Files
- Streams For the Win: A Performance Comparison of Node.js Methods for Reading Large Datasets (Pt 2)
📌 Methodologies and Guidelines
ESTlint, tool for identifying and reporting on patterns found in ECMAScript/JavaScript code.
NPM ESLint
NPM ESLint | Airbnb
📐 Infrastructure
Install NodeJS Dependences
$npm iRunning the App
# If your NodeJS version is previous than v13.2.0
$node --experimental-modules ./src/'folder'/'file.mjs'
# If your NodeJS version is v13.2.0 or higher
$node ./src/'folder'/'file.mjs'Generate the SSL Certificate for localhost
# If you want use http2 you need generate localhost certificate
$openssl req -x509 -newkey rsa:2048 -nodes -sha256 -subj '/CN=localhost' \ -keyout localhost-privkey.pem -out localhost-cert.pem📂 Code scaffolding
/
├── assets 🌈 # Images Sources.
| └── ... # ...
| |
├── env 🔌 # Configure enviroments deploy.
| └── ... # ...
| |
├── src 💯
| ├── usage-example # Usage & Example.
| | ├── example01 # Http server return pain text.
| | └── example02 # Http server return json object.
| |
| ├── assertion-testing # Assertion Testing.
| | ├── example01 # Equal numbers or not with assert.strictEqual method.
| | ├── example02 # Equal numbers and string or not with assert.equal method.
| | ├── example03 # Equal arrays values and structure or not with strict.deepEqual method.
| | ├── example04 # Equal objects values and structure or not with strict.deepEqual method.
| | └── example05 # Http request with Reject results and objects results with structure and typeof control.
| |
| ├── async-hooks # Async Hooks.
| | ├── example01 # Create http server with external request to get content. This functions launch async hooks and save into .log file.
| | ├── test.log # Log example file.
| | └── ... # ...
| |
| ├── buffer # Buffer.
| | ├── example01 # Create first safe and not Buffer empty and with string.
| | ├── example02 # Get length of string and buffer string.
| | ├── example03 # Is Buffer and is Encoding functions.
| | ├── example04 # Work with compare, concat, equal, includes, indexOf, lastIndeOf, keys and slice functions.
| | ├── example05 # Work with toString and toJSON functions.
| | └── ... # ...
| |
| ├── child-processes # Child Processes.
| | ├── example01 # spawn function.
| | ├── example02 # exec and execSync functions.
| | ├── example03 # spawn and spawnSync functions.
| | ├── example04 # exec and spawn functions with custom sh file.
| | ├── example05 # exec and spawn functions with magick tool (you need install imagemagick library).
| | ├── example06 # execFile and execFileSync functions.
| | ├── example07 # fork function with example messages to childs.
| | ├── example07-sub01 # sub process message fork function.
| | ├── example07-sub01 # sub process message fork function.
| | ├── example08 # fork function with process ls and sh.
| | ├── example08-sub01 # sub process spawnSync ls fork function.
| | ├── example08-sub01 # sub process spawnSync sh fork function.
| | ├── test.sh # Sh example file.
| | ├── cat.jpg # Image cat example.
| | └── ... # ...
| |
| ├── cluster # Cluster.
| | ├── example01 # Show CPUs number and create a cluster for each core.
| | ├── example02 # Control cluster waiting or working any task.
| | └── ... # ...
| |
| ├── console # Console.
| | ├── example01 # Basic console log, error and warn.
| | ├── example02 # Console log with params added.
| | ├── example03 # Show and get log and save into .log files (out and error files).
| | ├── example04 # Clear console with setTimeout into async function.
| | ├── example05 # Assert, count, countReset.
| | ├── example06 # Group and groupEnd.
| | ├── example07 # Time and timeEnd.
| | ├── example08 # Table with arrays of numbers, objects and more arrays of strings.
| | └── ... # ...
| |
| ├── esm # ECMAScript Modules.
| | ├── example01 # Import esm module with .js extension file.
| | ├── example02 # Import esm module from "libs" folder into your js application with .js extension file.
| | ├── example03 # Import esm submodule from "libs" folder into your js application with .js extension file.
| | └── ... # ...
| |
| ├── errors # Errors.
| | ├── example01 # Variable no defined into try/catch.
| | ├── example02 # With properties of an object in try/catch.
| | ├── example03 # In callback functions.
| | ├── example04 # In try/catch with async and sync functions.
| | ├── example05 # Custom message Error into throw.
| | └── ... # ...
| |
| ├── events # Events.
| | ├── example01 # Differents instances and times.
| | ├── example02 # Define arguments and show.
| | ├── example03 # Extends class EventEmitter and create main scope with custom properties.
| | ├── example04 # What happens to the functions: setTimeout, setImmediate and process.nextTick.
| | ├── example05 # Handling events only once.
| | ├── example06 # Remove event with removeListener.
| | ├── example07 # Set Max Listeners to event with setMaxListeners.
| | └── ... # ...
| |
| ├── file-system # File System.
| | ├── example01 # Open and close file by name with concrete path.
| | ├── example02 # Open and close with Url and Buffer.
| | ├── example03 # Get File Descriptors with stat function from json and txt files.
| | ├── example04 # Open folder and file details with opendirSync and openSync functions.
| | ├── example05 # Read folder and file content with readdirSync and readFileSync functions.
| | ├── example06 # Get folder content with Callback, Sync and Promises.
| | ├── example07 # Get file list of folder and content files with Sync.
| | ├── example08 # Get if directory is or not directory and file is or not file.
| | ├── example09 # Access function for get if file exist or not.
| | ├── example10 # Append function for include new data inside file.
| | ├── example11 # Chmod function for set and change permissions of a file.
| | ├── example12 # Chown function for set and change owner and group of a file.
| | ├── example13 # Copy function for copy file from origin to destination.
| | ├── example14 # Create Read Stream from file for get all content and others.
| | ├── example15 # Create file and Write Stream of new file for save all content.
| | ├── example16 # Create symbolic link with link function.
| | ├── example17 # Create directories with mkdir, mkdirSync.
| | ├── example18 # Create temp directories with mkdtemp and mkdtempSync.
| | ├── example19 # Rename file with rename and renameSync functions.
| | ├── example20 # Remove folders with rmdir and rmdirSync functions with recursive option.
| | ├── example21 # Remove files with unlink and unlinkSync functions.
| | ├── example22 # Create listener for get if change the folder and files content.
| | └── ... # ...
| |
| ├── http # HTTP.
| | ├── example01 # Get methods and status codes from http.
| | ├── example02 # Create http server and show lifecycle-events.
| | ├── example03 # Create http server with custom routers and reponses for POST or GET methods.
| | ├── example04 # Request to url with method GET and port 80 and received JSON object.
| | ├── example05 # Request to url with method POST and port 80 send and received JSON object.
| | └── ... # ...
| |
| ├── http2 # HTTP2.
| | ├── example01 # Create http2 server and response html elements.
| | ├── example02 # Create http2 server and show lifecycle-events.
| | ├── example03 # Create http and http2 server and see all differences.
| | | ├── example03-http # Create http server and return static file. See that the connection open and close for each request.
| | | └── example03-https # Create http2 server and return static file. See that the connection open one time and not close for each request.
| | ├── example04 # Create http2 server and with html file and push css and js file.
| | └── ... # ...
| |
| ├── https # HTTPS.
| | ├── example01 # Create https server and response html elements.
| | ├── example02 # Request to url with method GET and port 443 and received JSON object.
| | └── ... # ...
| |
| ├── inspector # Inspector.
| | ├── example01 # Create inspector instance and config host and port.
| | ├── example02 # Send console log, warn, info and error.
| | ├── example03 # Send console table.
| | ├── example04 # Create new session for any inspector and report via console.
| | ├── example05 # Create new session for any inspector and write profile.cpuprofile file.
| | └── ... # ...
| |
| ├── intl # Internationalization.
| | ├── example01 # toLowerCase and toUpperCase functions with String.
| | ├── example02 # Collator functions for get order string and sort string by order.
| | ├── example03 # DateTimeFormat for get date with differents languaje and formats.
| | ├── example04 # NumberFormat for format numbers with differents languaje and formats.
| | └── ... # ...
| |
| ├── modules # Modules.
| | ├── example01 # Module Exports and Require consts with strings values.
| | ├── example02 # Module Exports and Require function for sum two digits.
| | ├── example03 # Module Exports and Require class with methods.
| | ├── example04 # Module Exports and Require classes extends with methods.
| | ├── example05 # Module Exports and Require classes extends with static method.
| | ├── example06 # Export Default and Import class extends with static method.
| | ├── example07 # Export and Import classes extends with static method.
| | ├── example08 # Two Require of the same Module assign with Require Cache just once.
| | ├── example09 # Require JS Module and JSON File.
| | ├── example10 # Require JS Module from folder with Package.json file.
| | └── ... # ...
| |
| ├── net # Net.
| | ├── example01 # Server and Client with emit messages and Close Socket Connection.
| | ├── example02 # Server and Client with severals messages from client Without Close Socket.
| | ├── example03 # Server and Two Clients send severals messages to all clientes Without Close Socket.
| | ├── example04 # Server and two clients and send Message to differents client Pear to Pear.
| | └── ... # ...
| |
| ├── os # OS.
| | ├── example01 # Get and show CPUs numbers and props.
| | ├── example02 # Get and show Free and Total System Memmory.
| | ├── example03 # Get and show Home Directory.
| | ├── example04 # Get and show Host Name Machine.
| | ├── example05 # Get and show Network Interfaces and props.
| | ├── example06 # Get and show Platform and Release.
| | ├── example07 # Get and show Temporal Directory.
| | ├── example08 # Get and show User Info.
| | ├── example09 # Get and show Operating System Constants.
| | └── ... # ...
| |
| ├── path # Path.
| | ├── example01 # Get Basename of current or specific folder.
| | ├── example02 # Use basename for get all internal files from folder and get basename of files.
| | ├── example03 # Use dirname for get the main folder and all internal files.
| | ├── example04 # Use extname for get extension of file name or all path.
| | ├── example05 # Get if any path is absolute.
| | ├── example06 # Use joins method for concat all string for create a correct path.
| | ├── example07 # Use normalize method for create corrects paths.
| | ├── example08 # Use parse method for get object with all properties of paths.
| | ├── example09 # Use relative method for compare two path and get an absolute path.
| | ├── example10 # Use sep method for generate array with split and resolve a structure with folders and files.
| | └── ... # ...
| |
| ├── perf-hooks # Performance Hooks.
| | ├── example01 # Timer and measure for JSON parse and stringify functions examples.
| | ├── example02 # Timer and measure for Get all files from specific folders in a function with callback.
| | ├── example03 # Timer and timerify wrapper for Get all files from specific folder with function with callback.
| | ├── example04 # Timers with severals externals request https for others REST APIs.
| | ├── example05 # Show Measure and Mark timers with two Observers
| | ├── example06 # Get duration timer of severals require functions of modules.
| | └── ... # ...
| |
| ├── process # Process.
| | ├── example01 # Use beforeExit event for get when event loop has no additional work to schedule.
| | ├── example02 # Send message between procces, one http server and other write into file.
| | ├── example03 # Use multipleResolves event for tracking potential errors in an application while using the Promise constructor.
| | ├── example04 # Use multipleResolves event with Promise.race() method returns a promise that fulfills or rejects as soon as one of the promises.
| | ├── example05 # Use unhandledRejection event for get all promise without catch.
| | ├── example06 # Use uncaughtException event for get all error of function without try/catch control.
| | ├── example07 # Use warning event for example to get exceeded listener of Event Emitter.
| | ├── example08 # The argv property contain all arguments include via CLI.
| | ├── example09 # The process.cwd() method returns the current working directory of the Node.js process.
| | ├── example10 # The process.emitWarning() method can be used to emit custom or application specific process warnings.
| | ├── example11 # The process.execArgv property returns the set of Node.js-specific command-line options passed when the Node.js process was launched.
| | ├── example12 # The process.exit() method instructs Node.js to terminate the process synchronously with an exit status of code.
| | ├── example13 # Use getegid, geteuid, getgid, getgroups and getuid functions for show info process identity.
| | ├── example14 # The bigint version of the process.hrtime() method returning the current high-resolution real time in nanoseconds.
| | ├── example15 # The process.memoryUsage() method returns an object describing the memory usage of the Node.js process measured in bytes.
| | ├── example16 # process.nextTick() adds callback to the "next tick queue".
| | ├── example17 # pid, platform, ppid, release props for get additional data of process and NodeJS release.
| | ├── example18 # Returns object the resource usage for the current process.
| | └── ... # ...
| |
| ├── querystring # Query String.
| | ├── example01 # Use querystring.encode for encode json object to url params.
| | ├── example02 # Use querystring.decode for decode url with several params to json object.
| | └── ... # ...
| |
| ├── readline # Readline.
| | ├── example01 # Use createInterface and create question and show user answer.
| | ├── example02 # To exit this process you just have to press <ctrl> + C.
| | ├── example03 # Get content for show from txt file for create interface.
| | ├── example04 # Use "process.stdin" events to get more interactions.
| | ├── example05 # Use line, close, pause and resume of readline for get events.
| | ├── example06 # Use keypress, keyup and keydown for get "process.stdin" events.
| | └── ... # ...
| |
| ├── repl # REPL.
| | ├── example01 # Create REPL and press .help for show all help commands.
| | ├── example02 # Create and press 2 times ^C again or ^D or type .exit.
| | ├── example03 # Run REPL, create a function and execute it..
| | ├── example04 # Create "replServer" and use defineCommand for include Specific Commands.
| | └── ... # ...
| |
| ├── report # Diagnostic Report.
| | ├── example01 # Write error and report to generic json file with an example.
| | ├── example02 # Write error and report to concrete file with an example.
| | ├── example03 # Launch an error and getReport to show javascriptStack object..
| | ├── example04 # Show errors and reports via EventEmitter.
| | └── ... # ...
| |
| ├── stream # Stream.
| | ├── example01 # Write severals string into file.txt with .write function.
| | ├── example02 # Include callbacks for open, ready, finish, open and error events.
| | ├── example03 # Write big file with .write method with this result: 1,1G stream-big-example03.txt.
| | ├── example04 # Show how many seconds the function fs.writeFile and fs.createWriteStream needs to perform the same task.
| | ├── example05 # Create origin and destination Stream and use gzip for compress file destination.
| | ├── example06 # Create origin Stream, Custom transform Stream and destination Stream for replace text from origin to destination file.
| | ├── example07 # Http server and Read Stream for create gz file from txt file and download with browser.
| | ├── example08 # Http server and Read Stream for return html file with gzip encoding.
| | ├── example09 # Readable with iterate function with yield.
| | ├── example10 # Readable with iterate array.
| | ├── example11 # Readable Stream with iterate map with severals objects items.
| | ├── example12 # Readable Object with iterate map and two pipes for work with severals Streams Writables.
| | ├── example13 # Parallel Pipes with Readable from array with iterate map, transform and Write with two Stream file.
| | ├── example14 # Sequentials Pipes with end option to false and Readable and Duplex with write functions more info with timeouts.
| | ├── example15 # Sequentials Pipes and Readable with autoClose option to false and Duplex with end option to false and set severals writes functions.
| | ├── example16 # Work with Readline and Write Stream to save line by line.
| | ├── example17 # Create Stream from origin file, replace all emails to * characters and save into new Stream file.
| | └── ... # ...
| |
| ├── timers # Timers.
| | ├── example01 # timeout vs immediate.
| | ├── example02 # timeout vs immediate with inside timers.
| | ├── example03 # timeout vs severals immediate.
| | ├── example04 # timeout vs immediate vs nextTick.
| | ├── example05 # nextTick with try/catch and not block timeout and immediate.
| | ├── example06 # timeout, immediate, nextTick and promises inside this with try/catch/finally.
| | ├── example07 # timeout, immediate, nextTick and promises inside this with then/catch/finally.
| | └── ... # ...
| |
| ├── util # Util.
| | ├── example01 # Use .callbackify method with async function.
| | ├── example02 # Use .callbackify method with Promise.
| | ├── example03 # Return with .debuglog method param.
| | ├── example04 # Return with .debuglog method severals params.
| | ├── example05 # Return console with color in terminal and params.
| | └── ... # ...
| |
| ├── worker-threads # Worker Threads.
| | ├── example01 # Create Worker with the same file..
| | ├── example02 # Create Worker with differents files for create two parallels tasks.
| | ├── example03 # Create two Worker and send messages with parent.
| | ├── example04 # Create ten Worker and send messages to parent with finish setTimeout with random time.
| | ├── example05 # Create Worker when update the content of local json file for change it and save into other file.
| | └── ... # ...
| |
| ├── zlib # Zlib.
| | ├── example01 # Compress to zip destination file from txt file how source.
| | ├── example02 # Compress jpg file to zip file and decompress zip for get jpg origin file.
| | ├── example03 # Create .gz file from jpg file and uncompress with createGunzip method.
| | ├── example04 # Create severals .gz file with gzip, deflate and brotli methods. You can see which one is more efficient.
| | ├── example05 # Create http server and return html file with Brotli Compress via response Stream.
| | ├── example06 # Create http server and Static files into a public folder.
| | └── ... # ...
| |
| └── ...
└── ...
⛽️ Review and Update Dependences
For review and update all npm dependences of this project you need install in global npm package "npm-check-updates" npm module.
# Install and Run
$npm i -g npm-check-updates
$ncuHappy Code
Created with JavaScript, lot of ❤️ and a few ☕️