A complete guide to Node.js

  • 1,128 views
Uploaded on

A complete guide to start server side javascript programming called Node.js by Er. Prabin Silwal.

A complete guide to start server side javascript programming called Node.js by Er. Prabin Silwal.

More in: Education
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Be the first to comment
No Downloads

Views

Total Views
1,128
On Slideshare
0
From Embeds
0
Number of Embeds
0

Actions

Shares
Downloads
57
Comments
0
Likes
3

Embeds 0

No embeds

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
    No notes for slide

Transcript

  • 1. Complete Guide On Node.js By: Senior Developer Prabin Silwal
  • 2. What you should know before? Javascript Unix command
  • 3. Installation:3way to install • 1st way: Nodejs.org : – You can download pre-compiled binary – Easy installation – Automatic configured environment – But, updates require reinstallation – And switching versions need reinstallation
  • 4. 2nd way : Version manager(nvm): Install any version quickly Switch version quickly Easy install on Linux But no widzard based installation(must use command line interface) And reinstall global modules when switching version Install version manager then node
  • 5. 3rd way : Compile it from source(node) Get absolute new node Customize your installation But you must be familiar with compiling process And takes longer And not easy to switch
  • 6. Which is preferable? • For mine 2nd way
  • 7. Window installation: • Download node.js • Click install
  • 8. Checking after installation? • Run command • Type “node” and hit enter • Type “console.log(‘your text’)”
  • 9. Note that previous installation process needs re installation for new updates.
  • 10. Installing using nvm in Linux(Not wizard mode for Linux):
  • 11. Make ready to install by following command: • sudo apt-get install git • sudo apt-get install curl
  • 12. Install using command:
  • 13. Why node.js ? • It is js with browser • JS for both front end and backend (eg: using jquery) • Native support • It’s fast because it’s mostly C code
  • 14. What can you build? • • • • Websocket server ( Like chat server) Fast file upload client Ad server Any Real- Time Data Apps
  • 15. What is Node.js not: • Web framework • For Beginners (it’s very low level) • Multi- threaded (You can think of it as a single threaded server)
  • 16. Few variables you are familiar about web browser: • window : (Type in console of chrome) The window object have functions and attributes that have to do something with window being drawn in screen.
  • 17. • location: (Type in console of chrome) The location object has all the information about url that being loaded.
  • 18. • document : (Type in console of chrome) The document object contains all oh html displayed in page
  • 19. Now type in node console: • It displays undefined message
  • 20. Why not work in node? • Because node is not just an instance , so “global” is defined in node but not in chrome console where you can get instance version of global object called window.
  • 21. • This global object has several functions (which are not in chrome console) • EG: require function: used to pull in different javascript script files from your appliction
  • 22. But error in chrome console:
  • 23. Some works on both: • Eg: console
  • 24. Note: local variable vs global • Eg: name = prabin; //global Var name = prabin; //local
  • 25. Node is Non-blocking: Blocking vs Noblocking 1
  • 26. Blocking vs No-blocking 2
  • 27. Blocking vs No-blocking 3
  • 28. Callback alternate syntax:
  • 29. MODULES
  • 30. REQUIRING MODULES var http = require('http'); //http.js va r fs = require('fs'); // fs.js How does ‘require’ return the libraries? How does it find these files?
  • 31. Custom Module Example: • Prabin_App(base folder) – Example.js var say = require(‘./say_hello_module.js’); //say is assigned as object & has 2 properties : softly and loudly which both are functions say.softly(‘prabin’); Say.loudly(‘PRABIN’); – Say_hello_module(Module Folder) • index.js var hello = function (message) { console.log(‘say hello:’+message); }); exports.slowly = hello;//we first declare hello as function and setting slowly to be value of hello exports.loudly = function(message) { console.log(‘SAY HELLO:’+message); });
  • 32. LETS CREATE OUR OWN MODULE
  • 33. • For finding modules:
  • 34. NPM: THE USERLAND SEA “Core” is small. “Userland” is large. Package manager for node • Comes with node • Module Repository • Dependency Management • Easily publish modules • “Local Only”
  • 35. INSTALLING A NPM MODULE /Home/my_app • $ npm install request https://github.com/mikeal/request Installs into local node_modules directory ---------------after installation------------------------------Home/my_app/node_modules/request ----For require/using in your app-----------------------------------/Home/my_app/app.js va r request = require('request');//Loads from local node_modules directory
  • 36. LOCAL VS GLOBAL MODULE • Install modules with executables globally: $ npm install coffee-script –g //global $ coffee app.coffee Note: Global npm modules can’t be required $ npm install coffee-script //Install locally
  • 37. FINDING MODULES • From npm command line: $ npm search module_name Eg: $ npm search request
  • 38. DEFINING YOUR DEPENDENCIES my_app/package.json { "name": "My App", "version": "1", "dependencies": { "connect": "1.8.7" } } Then: $ npm install will installs it into the node_modules directory i.e. my_app/node_modules/connect
  • 39. • SEMANTIC VERSIONING: Major Minor Patch 1 . 8 . 7
  • 40. Test Time
  • 41. NODE.JS : Hello world Hello.js var http = require('http'); http.createServer(function(request, response) { response.writeHead(200); //Status code in browser response.write("Hello World.");//ResponseText response.end();//Close the connection }).listen(8080);//Listen for connection on this port console.log('Listening on port 8080...');
  • 42. • Run the server: $ node Hello.js (Listening on port 8080...) • View output $ curl http://localhost:8080 (Hello World)
  • 43. Event Loops 1
  • 44. Event Loops 2
  • 45. Long Running Process var http = require('http'); http.createServer(function(request, response) { response.writeHead(200); response.write(“Hello World running."); response.end(); setTimeout(function() //Represent long running process { response.write(" Hello World is done."); response.end(); }, 5000); //5000ms = 5 seconds }).listen(8080);
  • 46. TWO CALLBACKS HERE var http = require('http'); request http.createServer(function(request, response) { response.writeHead(200); response.write(“Hello World running."); response.end(); timeout setTimeout(function() //Represent long running process { response.write(" Hello World is done."); response.end(); }, 5000); //5000ms = 5 seconds }).listen(8080);
  • 47. TWO CALLBACKS TIMELINE
  • 48. (With blocking timeline)
  • 49. NOTE: TYPICAL BLOCKING THINGS • Calls out to web services • Reads/Writes on the Database • Calls to extensions
  • 50. EVENTS IN THE DOM • The DOM triggers Events you can listen for those events
  • 51. EVENTS IN NODE 1 • Many objects in Node emit events
  • 52. EVENTS IN NODE 2
  • 53. Also there is custom EventEmitter var EventEmitter = require('events').EventEmitter;
  • 54. var http = require('http'); http.createServer(function(request, response){ ... }); But what is really going on here? http://nodejs.org/api/
  • 55. Breaking It down var http = require('http');
  • 56. ALTERNATE SYNTAX
  • 57. Streams
  • 58. STREAMING RESPONSE Readable stream Writable stream http.createServer(function(request, response) { response.writeHead(200); response.write(“Hello World Writing."); setTimeout(function() { response.write(" Hello World is done."); response.end(); }, 5000); }).listen(8080); Output to client: Hello World Writing. (5 seconds later) Hello World is done.
  • 59. HOW TO READ FROM THE REQUEST?
  • 60. $ curl -d 'hello' http://localhost:8080 Output on client: hello
  • 61. READING AND WRITING A FILE var fs = require('fs'); // require filesystem module var file = fs.createReadStream("readme.md"); var newFile = fs.createWriteStream("readme_copy.md"); require filesystem module file.pipe(newFile);
  • 62. UPLOAD A FILE var fs = require('fs'); var http = require('http'); http.createServer(function(request, response) { var newFile = fs.createWriteStream("readme_copy.md"); request.on('end', function() { response.end('uploaded!'); }); }).listen(8080); On Client: $ curl --upload-file readme.md http://localhost:8080 Output on client: uploaded!
  • 63. DOCUMENTATION http://nodejs.org/api/
  • 64. REMEMBER THIS CODE 1? var fs = require('fs'); var newFile = fs.createWriteStream("readme_copy.md"); var http = require('http'); http.createServer(function(request, response) { request.pipe(newFile); request.on('end', function() { response.end('uploaded!'); }); }).listen(8080);
  • 65. REMEMBER THIS CODE 2? http.createServer(function(request, response) { var newFile = fs.createWriteStream("readme_copy.md"); var fileBytes = request.headers['content-length']; var uploadedBytes = 0; request.pipe(newFile); request.on('data', function(chunk) { uploadedBytes += chunk.length; var progress = (uploadedBytes / fileBytes) * 100; response.write("progress: " + parseInt(progress, 10) + "%n"); }); }).listen(8080);
  • 66. Express
  • 67. Express
  • 68. SOCKET.IO
  • 69. SOCKET.IO • Traditional
  • 70. Persisting Data
  • 71. Persisting Data
  • 72. References: • IN T R O T O N O D E . J S (Authorized site) • Ihrig C. J. - Pro Node.js for Developers • Gackenheimer C. - Node.js Recipes
  • 73. Thank You • Any Suggestions and queries : Website: http://prabinsilwal.com.np Email: silwalprabin@hotmail.com