Does anyone know if its possible to append a json object in a loop?-CodePudding

I can't work out if its possible to do this... I am currently getting this output

{"BUSINESS":[{"title":"Luling City Market"},{"image":"https://i1.ypcdn.com/blob/f714c6a156c8bb5fb93178c0b1c4bc038dd96ec9_150x150_crop.jpg"}]}{"BUSINESS":[{"title":"Barry's Pizza"},{"image":"https://i1.ypcdn.com/blob/3b90e6b5687f5edf98e1abf1e9f74ddaf8f90e1d_150x150_crop.jpg"}]}{"BUSINESS":[{"title":"Luling City Market"},{"image":"https://i2.ypcdn.com/blob/f714c6a156c8bb5fb93178c0b1c4bc038dd96ec9_150x150_crop.jpg"}]}

From:

const puppeteer = require('puppeteer');
var fs = require('fs');

async function scrapeProduct(url){
const file = fs.readFileSync('restaurants.json')

var scrapeTitle = '//*[@id="main-header"]/article/div/h1';
var scrapeImage = '//*[@id="main-header"]/article/a/img';

const browser = await puppeteer.launch();
const page = await browser.newPage();
await page.goto(url);

const [el] = await page.$x(scrapeImage);
const src = await el.getProperty('src');
const image = await src.jsonValue();

const [el2] = await page.$x(scrapeTitle);
const txt = await el2.getProperty('textContent');
const title = await txt.jsonValue();

console.log({image, title});
var product = {
    'BUSINESS_TITLE' : [title],
    'BUSINESS_IMAGE' : [image]
}

if (file.length == 0){

    fs.writeFile('restaurants.json', JSON.stringify(product), (err) =>{
        if (err) { console.error(err); return; };
        console.log('Created File');
    })
}else{

    fs.appendFile('restaurants.json', JSON.stringify(product), (err) =>{
        if (err) { console.error(err); return; };
        console.log('Updated File');
    })
}

browser.close();
}

var urls = [
'https://www.yellowpages.com/houston-tx/mip/luling-city-market-1615603?lid=1000597596315',
'https://www.yellowpages.com/houston-tx/mip/barrys-pizza-472089383?lid=1001593326336'
]

for(var val in urls){
    scrapeProduct(urls[val]);
}

Of which is not the right way to format a JSON file...

To ensure that it formatted correctly, it should be more like this:

{"BUSINESS-TITLE":["1","2"],"BUSINESS-IMAGE":["1","2"]}

CodePudding user response：

Instead of append you can do first JSON.parse(file) then update the content with the new product and finally fs.writeFile('restaurants.json', JSON.stringify(updatedProducts))

CodePudding user response：

The simplest and valid way of doing this would be in three steps:

Step 1: Parsing the json file to an array.

Step 2: Appending the object to that array.

Step 3: Stringifying and saving that to your file.