A-simple-Expressjs-nodejs-D3-MySql-visualization

Creating a minimal simple visualization by the nodejs framework ExpressJs and D3.js Library using MySql Database. It uses a pool connection

How to do that?

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ExpressJs

• Create a folder myapp, go in there.
• Install ExpressJs npm init npm install express --save
• You can see ExpressJs Installation for more information.
• Create this file index.html *Create simplevis.js and copy the codes there.

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D3 and DB

• Take a look at Donut Canvas https://bl.ocks.org/mbostock/2394b23da1994fc202e1
• Take a look at data in the page bottom, import it to a age_population table in the test database
• Create a js file donut.js in Folder (create it) static/js/. We call it below.
• Go to a folder and Install node-mysqldb and HTTP by npm install mysql npm install http

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Integration

• Take a look at simplevis.js, we have two routes there app.get('/data.json', (req, res) => { res.writeHead(200, {'Content-Type': 'text/html;charset=utf-8'}); con.query("SELECT * FROM age_population", function (err, result) { res.write(JSON.stringify(result)); res.end(); }); }); Is for fetching data and sending as json request in the data.json url. Also, app.get('/', (req, res) => { res.sendFile(path.join(__dirname + "/index.html")); }) render the index.html to serve in / address.
• Start project node simplevis.js *Go to http://127.0.0.1:3000/. sAlso, you can check http://127.0.0.1:3000/data.json path for the json data.