(1) automatic construction of front-end projects
1. Create myProject project files and corresponding folders
var projectData ={
'name':'myProject',
'fileData':[
{
'name':'css',
'type':'dir'
},{
'name':'js',
'type':'dir'
},{
'name':'images',
'type':'dir'
},{
'name':'index.html',
'type':'file',
'content' : '<html>\n\t<head>\n\t\t<title>title</title>\n\t</head>\n\t<body>\n\t\t<h1>Hello</h1>\n\t</body>\n</html>'
}
]
};
var fs = require('fs');
if(projectData.name){
// Create project folder
fs.mkdirSync(projectData.name);
var fileData = projectData.fileData;
if(fileData && fileData.length){
fileData.forEach(function(file){
//File or folder path
file.path = './'+projectData.name +'/'+ file.name;
//Create files or folders based on type
file.content = file.content || '';
switch(file.type){
case 'dir':
fs.mkdirSync(file.path);
break;
case 'file':
fs.writeFileSync(file.path,file.content);
break;
default:
break;
}
});
}
}2. Package multiple files automatically
var fs = require('fs');
var filedir = './myProject/dist';
fs.exists(filedir,function(isExists){
if(!isExists){
fs.mkdirSync(filedir);
}
fs.watch(filedir,function(ev,file){
//As long as one file changes, we need to read and merge all files under the folder
fs.readdir(filedir,function(err,dataList){
var arr = [];
dataList.forEach(function(file){
if(file){
//statSync view file properties
var info = fs.statSync(filedir + '/' +file);
//mode file permission
if(info.mode === 33206){
arr.push(filedir + '/' +file);
}
}
});
//Read the contents of the file in the array
var content = '';
arr.forEach(function(file){
var c = fs.readFileSync(file);
content += c.toString()+'\n';
});
//Merge content in file
fs.writeFileSync('./myProject/js/index.js',content);
})
});
});
(2) using node for web development
1. Build an http server to process http requests sent by users
//Load an http module
var http = require('http');
//Create and return a web server object through createServer under http module
var server = http.createServer();
//Open the HTTP server listening connection. The server will not work until the listen method is called
server.listen(8000,'localhost');
//Is the server listening for connections
server.on('listening',function(){
console.log("listening..........");
});
//Triggered every time a request is received, there may be multiple requests per connection (in the case of an HTTP keep alive connection).
server.on('request',function(){
res.write('<p>hello</p>');
res.end();
});2. The request method has two parameters: request and response
1) request: an instance of http.IncomingMessage to obtain some requested information, such as header information, data, etc
Httpmission: version of http protocol used
headers: data in the request header
url: requested address
Method: method of request
2) response: an instance of http.ServerResponse, which can output a response to the requested client
write (chunk,encoding): Send a data block to the corresponding body
end (chunk,encoding): when all text and header messages are sent, the method is called to tell that the server data has been sent to completion. This method must be called after the completion of the information transmission, and is the last call.
statusCode: this property is used to set the returned status code
setHeader (name,value): set the return header information
writeHead (statusCode,reasonPhrase,headers) can only be used once in the current request, and must be called before response.end ().
3. Use fs module to separate behavior
var http = require('http');
var url = require('url');
var fs = require('fs');
var server = http.createServer();
//Path to html file
var htmlDir = __dirname + '/html/';
server.on('request',function(request,response){
var urlStr = url.parse(request.url);
//Match the corresponding html file according to pathname
switch(urlStr.pathname){
case '/':
sendData(htmlDir + 'index.html',request,response);
break;
case '/user':
sendData(htmlDir + 'user.html',request,response);
break;
case '/login':
sendData(htmlDir + 'login.html',request,response);
break;
default:
//Deal with other situations
sendData(htmlDir + 'err.html',request,response );
break;
}
});
function sendData(file,request,response){
//Read the file. If it exists, the corresponding read content will be returned. If it does not exist, the error message will be returned
fs.readFile(file,function(err,data){
if(err){
response.writeHead(404,{
'content-type':'text/html;charset=utf-8'
});
response.end('<h1>Page does not exist</h1>')
}else{
response.writeHead(200,{
'content-type':'text/html;charset=utf-8'
});
response.end(data);
}
})
}
server.listen(8000,'localhost');