Files
old-kivi/crawler/specific/olx.js
2016-11-10 13:04:45 +01:00

140 lines
3.9 KiB
JavaScript

'use strict'
let fetch = require('node-fetch');
let cheerio = require('cheerio');
let fs = require('fs');
const pagesToTake = 10;
export default class OlxCrawler {
constructor(fromPage = 0, toPage = 10, maxResults = 1000) {
this.fromPage = fromPage;
this.toPage = toPage;
this.maxResults = maxResults;
}
async indexSingle(url) {
try {
const res = await fetch(url);
const body = await res.text();
const $ = cheerio.load(body);
const title = $('#naslovartikla').text();
const price = $('#pc > p:nth-child(2)').text();
const size = $('#dodatnapolja1 > div:nth-child(1) > div.df2').text();
const rooms = $('#dodatnapolja1 > div:nth-child(2) > div.df2').text();
const address = $('#dodatnapolja1 > div:nth-child(5) > div.df2').text();
const location = $('#artikal_glavni_div > div.artikal_lijevo > div.op.pop.mobile-lokacija').attr('data-content');
const adType = $('#artikal_glavni_div > div.artikal_lijevo > div:nth-child(15) > div:nth-child(2) > div.df2').text();
const time = $('time').attr('datetime');
const olxId = $('#artikal_glavni_div > div.artikal_lijevo > div:nth-child(15) > div:nth-child(4) > div.df2').text();
const descriptions = $('.artikal_detaljniopis_tekst');
const latLngRe = /LatLng\(([0-9]+\.[0-9]+)\,\s+([0-9]+\.[0-9]+)\)/g;
const imgRe = /href":("[^"]*")/g;
const matches = latLngRe.exec(body);
let lng = '',
lat = '';
const images = [];
const imgMatches = body.match(imgRe);
for (let i = 0; imgMatches && i < imgMatches.length; i++) {
let img = imgMatches[i].replace("href\":", "")
img = img.replace("\"", "");
img = img.replace("\"", "");
images.push(img);
}
if (matches && matches.length >= 3) {
lat = matches[1];
lng = matches[2];
}
const data = {
url,
title,
price,
size,
rooms,
address,
location,
adType,
time,
olxId,
shortDescription: descriptions.first().text(),
longDescription: descriptions.last().text(),
lat,
lng,
images
};
return data;
} catch (e) {
console.error('Exception caught: ' + e);
}
return null;
}
async indexPage(pageNr, maxResults = 1000) {
try {
console.log('Starting to index page: ' + pageNr);
const url = `http://www.olx.ba/pretraga?vrsta=samoizdavanje&sort_order=desc&kategorija=23&sort_po=datum&kanton=9&stranica=${pageNr}`;
const res = await fetch(url);
const body = await res.text();
const $ = cheerio.load(body);
const hrefs = [];
const results = {};
$('#rezultatipretrage').find('.listitem').each((i, elem) => {
const href = $(elem).find('a').first().attr('href');
hrefs.push(href);
});
let actualNoOfResults = (hrefs.length <= maxResults) ? hrefs.length : maxResults;
for (let i = 0; i < actualNoOfResults; i++) {
console.log(`indexing: ${hrefs[i]}`);
const singleData = await this.indexSingle(hrefs[i]);
if (singleData) {
results[hrefs[i]] = singleData;
}
await this.sleep(500);
}
return results;
} catch (e) {
console.error('Exception caught:' + e);
}
}
async sleep(ms) {
return new Promise(resolve => setTimeout(resolve, ms));
}
async indexPages(start, end, maxResults = 1000) {
let results = {};
for (let i = start; i <= end; i++) {
let result = await this.indexPage(i, numberOfResults);
Object.assign(results, result)
await this.sleep(5000);
}
return results;
}
async crawl() {
let results = await this.indexPages(this.fromPage, this.toPage, this.maxResults);
return results;
}
}
//indexSingle('http://www.olx.ba/artikal/23198642/trosoban-stan-centar-josipa-vancasa/');