{"id":793,"date":"2021-04-12T04:41:50","date_gmt":"2021-04-11T21:41:50","guid":{"rendered":"https:\/\/bigdolphin.com.vn\/?p=793"},"modified":"2024-03-26T15:26:44","modified_gmt":"2024-03-26T08:26:44","slug":"tcp-ip-client-server-using-nodejs","status":"publish","type":"post","link":"https:\/\/bigdolphin.com.vn\/?p=793","title":{"rendered":"Simple TCP\/IP Client – Server Applications using NodeJS"},"content":{"rendered":"\n

TCP\/IP<\/strong> (Transmission Control Protocol over Internet Protocol) is a most basic client – server communication topology between two network device in network. It has two basic protocols: TCP and IP.<\/p>\n\n\n\n

\"\"
Topology of Client – Server communication based on TCP\/IP<\/em><\/strong><\/center><\/figcaption><\/figure>\n\n\n\n

Implement in NodeJS<\/h2>\n\n\n\n

1. Server<\/h3>\n\n\n\n

a. Call modules<\/h4>\n\n\n\n
\/\/ Asynchronous network API module\nvar net = require('net');\n\/\/ File system module to store data\nvar fs = require('fs');<\/code><\/pre>\n\n\n\n
b. Create server<\/h4>\n\n\n\n
\/\/ Create Server\nvar server = net.createServer(function(socket) {\n    \/\/ Log file\n    var logfile = fs.createWriteStream('server.log',{flags: 'a'});\n\n    \/\/ Callback function when there is error\n    logfile.on('error', function(err) {\n        \/\/ Print error to terminal\n        console.log(\"Log file: ERROR: \" + err);\n    });\n\n    \/\/ Forward received data to log file\n    socket.pipe(logfile);\n\n    \/\/ Callback function when data arrives\n    socket.on('data', function(data){\n        \/\/ Print raw data to terminal\n        console.log(data);\n        \/\/ Format data to UTF8 characters\n        var textChunk = data.toString('utf8');\n        \/\/ Print formatted data to terminal\n        console.log(textChunk);\n        \/\/ Respond to client\n        socket.write(\"OK\\r\\n\");\n    });\n\n    \/\/ Callback function when client disconnected\n    socket.on('end', function() {\n        console.log(\"Server: Client disconnected\");        \n    });\n\n    \/\/ Callback function when there is error\n    socket.on('error', function(err) {\n        \/\/ Print error to terminal\n        console.log(\"Server: ERROR: \" + err);\n    });\n});<\/code><\/pre>\n\n\n\n
c. Configure port<\/h4>\n\n\n\n
\/\/ Open port 2021\nserver.listen(2021, function() {\n    \/\/ Print to terminal if success\n    console.log(\"Server: listening !\\r\\n\");\n});<\/code><\/pre>\n\n\n\n
2. Client<\/h3>\n\n\n\n
a. Call modules<\/h4>\n\n\n\n
\/\/ Asynchronous network API module\nvar net = require('net');\n\/\/ File system module to store data\nvar fs = require('fs');<\/code><\/pre>\n\n\n\n
b. Create client<\/h4>\n\n\n\n
\/\/ Create Client\nvar client = new net.Socket();<\/code><\/pre>\n\n\n\n
c. Connect to server<\/h4>\n\n\n\n
\/\/ Connect to server\nclient.connect(2021, 'localhost', function() {\n    \/\/ Print to terminal if success\n    console.log('Connected');\n\n    \/\/ Create stream for log file    \n    var logfile = fs.createWriteStream('client.log',{flags: 'a'});\n    \/\/ Callback function when there is error\n    logfile.on('error', function(err) {\n        \/\/ Print error to terminal\n        console.log(\"Log file: ERROR: \" + err);\n    });\n\n    \/\/ Forward received data to log file\n    client.pipe(logfile);\n\n    \/\/ Send to Server\n    client.write(\"Sent from client!\");\n});<\/code><\/pre>\n\n\n\n
d. Receive response from server<\/h4>\n\n\n\n
\/\/ Callback function when data arrives\nclient.on('data', function(data) {\n    \/\/ Print to terminal\n    console.log('Received: ' + data);\n    \/\/ Kill client after server's response\n    client.destroy();\n});<\/code><\/pre>\n\n\n\n
e. Disconnection event<\/h4>\n\n\n\n
\/\/ Callback function when client disconnected\nclient.on('close', function() {\n    \/\/ Print to terminal\n    console.log('Connection closed');\n});<\/code><\/pre>\n\n\n\n
3. Test<\/h3>\n\n\n\n
Run server on terminal:<\/p>\n\n\n\n
nodejs tcp_server.js<\/code><\/pre>\n\n\n\n
Run client on termial:<\/p>\n\n\n\n
nodejs tcp_client.js<\/code><\/pre>\n\n\n\n
\"\"<\/figure><\/div>\n\n\n\n
4. Reference<\/h3>\n\n\n\n
https:\/\/github.com\/bigdolphin\/tcp-ip-nodejs<\/a><\/p>\n\n\n\n
https:\/\/nodejs.org\/api\/net.html<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"
Simple applications for TCP\/IP Client and Server based on NodeJS<\/p>\n","protected":false},"author":2,"featured_media":852,"comment_status":"open","ping_status":"open","sticky":false,"template":"single-with-sidebar","format":"standard","meta":{"gtb_hide_title":false,"gtb_wrap_title":false,"gtb_class_title":"","gtb_remove_headerfooter":false,"footnotes":""},"categories":[10],"tags":[13,12],"_links":{"self":[{"href":"https:\/\/bigdolphin.com.vn\/index.php?rest_route=\/wp\/v2\/posts\/793"}],"collection":[{"href":"https:\/\/bigdolphin.com.vn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/bigdolphin.com.vn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/bigdolphin.com.vn\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/bigdolphin.com.vn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=793"}],"version-history":[{"count":10,"href":"https:\/\/bigdolphin.com.vn\/index.php?rest_route=\/wp\/v2\/posts\/793\/revisions"}],"predecessor-version":[{"id":855,"href":"https:\/\/bigdolphin.com.vn\/index.php?rest_route=\/wp\/v2\/posts\/793\/revisions\/855"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/bigdolphin.com.vn\/index.php?rest_route=\/wp\/v2\/media\/852"}],"wp:attachment":[{"href":"https:\/\/bigdolphin.com.vn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=793"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/bigdolphin.com.vn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=793"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/bigdolphin.com.vn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=793"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}