Great node. js Reading notes

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Chapter II JS overview based on GOOGLEV8 engine

• Object.keys (o)
• Array methods: Traversing foreach, filtering filter, changing map
• Implements the String.prototype.trim ()
• Contains JSON parsing

Chapter III blocking and non-blocking IO single-threaded attention points

• Careful handling of in-memory variables may affect the results of two visits
• Do not write blocking code that may affect the time of a second visit

Event rotation

• Register Events First
• Keep asking if these events have been distributed dispatch
• When the event is distributed, the corresponding callback is triggered
• If the event does not fire, continue to execute other code
• It is not possible to catch exceptions thrown by functions that will be executed in the future.
• Avoid synchronizing IO

The Javascriptglobal object in the fourth chapter Nodez

• Corresponds to browser window

Process Object

• Process.nexttick = = Sertimeout (fn,1)

Module

• Require module exports
• Npm
• The absolute module refers to the node built-in module as well as the Node_modules module require (' FS ')
• Relative module refers to the module require ('./module ') found through a relative path
• Burst data EXPORTS.A (multiple), rewrite Module.exports (one)

# #事件

• Eventemitter
• Event listener on, event distribution emit, event removal RemoveListener
• Execute only once once
• The data event is partially arrived at, instead of a one-time full arrival return to you

Buffer

• Processing binary data

Fifth Chapter CLI &fs Apistream

• stdin readable stream Stdout/stderr writable stream
• Stdin.resume Waiting for user input
• console = = process.stdout.write (str + ' \ n ')

Fs

• Readdirsync (__dirname) readfilesync sync
• Readdir ('. ', async) readFile Async
• Createreadsteam read variable size has data, end events are used for pictures, large files, etc.
• Watchfile Monitor file changes

Process

• Parameters for PROCESS.ARGV operation
• PROCESS.CWD getting the current working directory
• PROCESS.ENV Environment variables
• Process.exit exit
• Signal Volume

Sixth Chapter TCPTCP

• Connection-oriented, IP-based protocol
• The IP protocol is out of order, TCP sends the IP containing the identifier and the data flow sequence information
• byte-oriented character and character encoding are completely ignorant, good flexibility
• Reliability three times handshake, window time re-hair
• Flow control, speed control for receiving and transmitting
• Congestion control to avoid congestion, the delay rate and packet loss rate will not be too high

Telnet

• When not the Telnet protocol is automatically downgraded to TCP
• Send get/http/1.1 Analog browser request, two times enter

Net

• node. JS Core TCP Module
• Data Close End Event
• Conn.setencoding (' Utf-8 ') or buffer.tostring (' Utf-8 ')
• Server-side Createserver client Connect method connect event

Seventh Chapter Httphttp

• TCP upper Layer protocol
• Content-type type text, HTML, XML, JSON, PNG
• The content length of the transfer-encoding:chunked output cannot be determined, and node's innate asynchronous mechanism can be formed accordingly.
• 301 Permanent Transfer 302 temporary transfer 304 resource not changed 403 unauthorized 404 Resource Not Found
• Form Content-type application/x-www-form-unencoded

HTTP Module

• Request, Response parameters
• To determine the route to Method+url
• QueryString module parses a string into an object
• The request method simulates a demand, passes back the data 2 binary, sets the Utf-8
• superagent Analog Client (impersonate a request) module
• Up Reboot Server module

Eighth Chapter Connect Toolset & Middleware

• Module: Connect
• Middleware Call Server.user (...)
• Log middleware Console.log ('%s%s ', Req.method, Req.url)
• Analog request time too long middleware, in Res.end is to clear the timer
• Static middleware to handle connect.static (' ... ')
• Query middleware Gets the queries string connect.query
• Logger middleware connect.logger (' Dev ')
• Body Parser Middleware Connect.bodyparser () if the JSON format is used in post, the body parser automatically goes to the JSON object, and the user uploads the file req.body.file multi-file form name using Name= "File[]"
• Seesion Middleware Session Connect.session use method Req.session.user
• Redis Session Persistence Middleware
• Methodoverride Middleware enables low-version browsers to support put, DELETE, PATCH
• BasicAuth Middleware user authentication

Nineth Chapter Expressexpress

• Web application Development Framework, based on Connect
• App.set (' View engine ', ' Ejs ') set up the Ejs template engine
• App.set (' View ', __dirname + '/view ') set the view layer path
• App.set (' View cache ', ' true ') sets the template cache
• Use App.get (), App.put (), app.post () to configure routing, pass parameters such as: ID, get req.params.id
• Res.render (' Search ', obj) render template
• Other settings case sensitive, strict routing, JSONP callback
• Provides a quick way for res and req render rendering, redirect redirection Req.header check header information
• Middleware App.user (function (req, res, next) {})
• Code organization layering, subcontracting, MVC, recommendations modeled after spring MVC

Template engine

Express/haml/jade/coffeekup/jquery Templates for node

#第十章WebSocket

Ajax

• Asynchronous javascripy
• An HTTP request, consumes network resources, and is not suitable for real-time service HTML5 WebSocket
• Based on WS-Protocol
• Node Support: Websocket.io
• Client New WebSocket

Defects

• Off does not mean disconnection, use heartbeat detection mechanism to determine
• Not friendly to JSON support
• Client temporary disconnect cannot resolve using timer or refresh page?
• Compatibility

11th Chapter Socket.io Advantage

• Cross-browser, support WebSocket is native, does not support the use of long connection, the connection will continue to open 20-50s
• Even if the browser-supported WebSocket is banned by the proxy or firewall, Socket.io will still use other technologies to resolve
• If the client stops transmitting information and does not shut down properly for a certain time, the connection is considered to be disconnected
• Auto-Reconnect when connection is lost
• Hierarchy of logic, with namespaces
• supports emit distribution and listen monitoring events

12th Chapter Mongodbmongodb

• Document oriented, the vast majority of cases are JSON
• Connect to New MongoDB. Server (' 127.0.0.1 ', 27017)
• API Open Insert Find Ensureindex FindOne
• $set setting $push push-in array

Mongoose

• Similar to the ORM framework in Java, simplifying database development
• Connection Mongoose.connect (' Mongodb://localhost/database ')
• Schema: A database model skeleton stored as a file, not capable of database operation
• Model: Generated by schema Publishing, database operations with abstract properties and behavior
• Entity: Entities created by model, his actions also affect the database
• Index Index title: {type:string, index:true} unique:true unique
• New Schema ({}). Pre (' Save ', function () {}) do some processing before saving
• Common API Find,findone,remove,update,count
• New Schema ({}). Find ({_id: ' xx '}). where (' title ', ' xxx '). Sort (' content ',-1). Limit (5). Run (function (err, data) {}) Similar JQ query
• . Select (' _id ', ' name ') Choose query specified field
• . Skip skips Mongoose. Schema.objectid Generating Random IDs
• Clazz: [clazz] Nested Sehema
• Clazz: {type:objectid, ref: ' Clazz '} Associated query
• Add static PersonSchema.statics.findByName via model call
• Add instance method PersonSchema.methods.findSimilarTypes entity call

13th Chapter Mysqlmysql

• Use query to execute SQL primarily
• have placeholders? Insert data (same as Java)
• Using the Seqelize node version ORM Framework

14th Chapter Redisredis

• Application scenario: Simple data model, data set. Suitable for storage in memory
• Seesion Persistence

15th. Code Share writing compatibility code

• Export module with front-end backend available

(function (module) {
Module.exports = function (A, b) {
return a+b;
}
If (' undefined '! = typeof window) {
Window.add = Module.exports;
}
}) (' undefined ' = = typeof module? {module: {exports: {}}}: module)

• To implement the ECMA: Extend a prototype or implement a tool function
• Eventemitter. Assert, XMLHttpRequest, DOM, WebSocket, Node-canvas are all implemented on Git
• Bowserbuild node module to browser-aware code

16th. Test assert

• Common API Ok,be/equal/eql/a/macth ...

Mocha

• Simplified writing
• Testing asynchronous code
• Generate reports

Great node. js Reading notes