replace old crawler, without specific crawler and saver implementation

This commit is contained in:
Bilal Catic
2019-09-16 15:59:53 +02:00
parent b28b160852
commit 76a989fa37
7 changed files with 305 additions and 513 deletions

28
app/common/enums.js Normal file
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const AD_TYPE = {
AD_TYPE_SALE: 1,
AD_TYPE_RENT: 2
};
const AD_CATEGORY = {
CATEGORY_FLAT: 0,
CATEGORY_HOUSE: 1,
CATEGORY_OFFICE: 2,
CATEGORY_LAND: 3,
CATEGORY_APARTMENT: 4,
CATEGORY_GARAGE: 5
};
const IGNORED_USERNAMES = [];
const REAL_ESTATE_STATUS = {
STATUS_NORMAL: 0,
STATUS_RESERVED: 1,
STATUS_SOLD: 2
};
module.exports = {
AD_TYPE,
IGNORED_USERNAMES,
AD_CATEGORY,
REAL_ESTATE_STATUS
};

55
app/crawler/crawl.js Normal file
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"use strict";
/*
Entry point for crawling functionality
All communication between crawlers and savers is here
All environment specific configuration is read here and
passed to the crawlers and savers.
*/
require("dotenv").config();
const OlxCrawler = require("./specific/olx");
const PostgresSaver = require("./savers/postgres");
let crawlers = [
// new OlxCrawler(
// process.env.OLX_FROM_PAGE,
// process.env.OLX_TO_PAGE,
// process.env.OLX_MAX_RESULTS
// )
// new ProstorCrawler(
// parseInt(process.env.PROSTOR_FROM_PAGE),
// parseInt(process.env.PROSTOR_TO_PAGE),
// parseInt(process.env.PROSTOR_MAX_RESULTS)
// ),
// new RentalCrawler(
// parseInt(process.env.RENTAL_FROM_PAGE),
// parseInt(process.env.RENTAL_TO_PAGE),
// parseInt(process.env.RENTAL_MAX_RESULTS)
// )
];
let savers = [new PostgresSaver(process.env.MONGO_URL)];
async function crawlAll() {
for (let crawler of crawlers) {
try {
const crawlerResults = await crawler.crawl();
for (let saver of savers) {
try {
await saver.connect();
await saver.save(crawlerResults);
} catch (e) {
console.log("Error saving. Trying next saver! ", e);
}
}
} catch (e) {
console.log("Error crawling. Trying next crawler! ", e);
}
}
for (let saver of savers) {
saver.close();
}
}
crawlAll();

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class PostgresSaver {
constructor(url) {
this.url = url;
}
connect() {
//TODO: It seems we never worry about open/close connection with Sequelize ?
//TODO: Check if postgres is ready
return true;
}
async save(results) {
let resultsForMongo = Object.keys(results).map(key => {
return results[key];
});
for (const doc of resultsForMongo) {
this.collection.update({ url: doc.url }, doc, { upsert: true });
}
}
close() {
//TODO: It seems we never worry about open/close connection with Sequelize ?
return true;
}
}
module.exports = PostgresSaver;

192
app/crawler/specific/olx.js Normal file
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"use strict";
let fetch = require("node-fetch");
let cheerio = require("cheerio");
const {
AD_TYPE,
AD_CATEGORY,
IGNORED_USERNAMES
} = require("../../common/enums");
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 username = $(
"#lg > div.desno2.profil > div:nth-child(2) > div.vrsta1.vrsta_desno > a > div.username > span"
).text();
if (IGNORED_USERNAMES.includes((username || "").toLowerCase())) {
return null;
}
const title = $("#naslovartikla").text();
const category = $(
"#artikal_glavni_div > div.artikal_lijevo > div:nth-child(3) > div > span:nth-child(3) > a > span"
).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 floor = $("#dodatnapolja1")
.find(":contains(Sprat)")
.last()
.nextAll()
.text();
const latLngRe = /LatLng\(([0-9]+\.[0-9]+)\,\s+([0-9]+\.[0-9]+)\)/g;
const matches = latLngRe.exec(body);
let lng = "",
lat = "";
const parseRooms = rooms =>
parseInt(
[...rooms]
.filter(c => !isNaN(c))
.filter(c => c.trim())
.join()
);
const parsePrice = price => parseFloat(price.replace(".", ""));
if (matches && matches.length >= 3) {
lat = matches[1];
lng = matches[2];
}
const parsedPrice = parsePrice(price);
let parsedRooms;
if (rooms === "Garsonjera") {
parsedRooms = 0;
} else {
parsedRooms = parseRooms(rooms);
}
const data = {
category: this.getCategoryId(category),
url,
title,
price: isNaN(parsedPrice) ? price : parsedPrice,
size: parseFloat(size),
rooms: parsedRooms,
floor: parseInt(floor),
address,
location,
adType: AD_TYPE.AD_TYPE_SALE,
time,
shortDescription: descriptions.first().text(),
longDescription: descriptions.last().text(),
lat,
lng,
loc: [parseFloat(lat), parseFloat(lng)]
};
return data;
} catch (e) {
console.error("Exception caught: " + e.message);
}
return null;
}
async indexPage(pageNr, maxResults = 1000) {
try {
console.log("Starting to index page: " + pageNr);
const url = `http://www.olx.ba/pretraga?vrsta=samoprodaja&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 < hrefs.length; 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);
}
}
getCategoryId(category) {
if (category === "Stanovi") {
return AD_CATEGORY.CATEGORY_FLAT;
} else if (category === "Zemljišta") {
return AD_CATEGORY.CATEGORY_LAND;
} else if (category === "Kuće") {
return AD_CATEGORY.CATEGORY_HOUSE;
} else if (category === "Poslovni prostori") {
return AD_CATEGORY.CATEGORY_OFFICE;
}
}
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, maxResults);
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;
}
}
module.exports = OlxCrawler;

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@@ -1,435 +0,0 @@
const fetch = require("node-fetch");
const cheerio = require("cheerio");
const { allRERequest, findPointInsideBoundingBox } = require("../db/dbHelper");
const { getRealEstateTypeEnum } = require("../enums");
const { getRegion, getMunicipality } = require("../codes");
const Promise = require("bluebird");
module.exports = class OlxCrawler {
//TODO figure best way to handle paging
constructor(hrefs = []) {
this.hrefs = hrefs;
}
async indexPages(urls) {
const indexers = [];
urls.forEach(url => {
indexers.push(new Indexer(url));
});
return Promise.map(indexers, function(indexer) {
return indexer.indexWithPagination();
}).then(async results => {
return results;
});
}
async crawl() {
const filteredResults = [];
const realEstateRequests = await allRERequest();
const urls = this.createRequestUrls(realEstateRequests);
let results = await this.indexPages(
urls,
this.fromPage,
this.toPage,
this.maxResults
);
const flatResults = results.flat();
if (flatResults) {
for (const finalResult of flatResults) {
if (null !== finalResult) {
if (
finalResult.lat !== undefined &&
finalResult.lat !== null &&
finalResult.lat !== ""
) {
const pointInsideBoundingBox = await findPointInsideBoundingBox(
[finalResult.lng, finalResult.lat],
finalResult.email,
finalResult.uuid
);
if (pointInsideBoundingBox[0].length !== 0) {
finalResult.hasLocation = true;
filteredResults.push(finalResult);
} else {
finalResult.hasLocation = false;
filteredResults.push(finalResult);
}
}
}
}
return filteredResults;
}
return [];
}
createRequestUrls(realEstateRequests) {
const urls = [];
for (const request of realEstateRequests) {
const {
realEstateType,
region,
sizeMin,
sizeMax,
priceMin,
priceMax
} = request;
const urlRealEstateParams = [
{
paramName: "kanton",
paramValue: region,
useParam: false
},
{
paramName: "kategorija",
paramValue: getRealEstateTypeEnum(realEstateType).olxid,
useParam: true
},
{
paramName: "kvadrata_min",
paramValue: sizeMin,
useParam: true
},
{
paramName: "kvadrata_max",
paramValue: sizeMax,
useParam: true
},
{
paramName: "od",
paramValue: priceMin,
useParam: true
},
{
paramName: "do",
paramValue: priceMax,
useParam: true
}
];
const urlResultsParams = [
{
paramName: "vrstapregleda",
paramValue: "tabela",
useParam: true
},
{
paramName: "sort_order",
paramValue: "desc",
useParam: true
},
{
paramName: "vrsta",
paramValue: "samoprodaja",
useParam: true
},
{
paramName: "stranica",
paramValue: "0",
useParam: true
}
];
const paramsReduceFunction = (accumulatedValue, currentParam) => {
const { paramName, paramValue, useParam } = currentParam;
if (useParam) {
return `${accumulatedValue}&${paramName}=${paramValue}`;
} else {
return accumulatedValue;
}
};
const reducedRealEstateParams = urlRealEstateParams.reduce(
paramsReduceFunction,
""
);
const reducedResultsParams = urlResultsParams.reduce(
paramsReduceFunction,
""
);
const olxUrl = {
url: `https://www.olx.ba/pretraga?${reducedRealEstateParams}${reducedResultsParams}`,
email: request.email,
uuid: request.uniqueId,
hrefs: this.hrefs
};
urls.push(olxUrl);
}
return urls;
}
};
class Indexer {
/**
*
* @param {String|Array} olxUrl single or array of objects containing url email and uuid
* @param {Array} hrefResutls array contaning urls from crawler results
*/
constructor(olxUrl, hrefResutls) {
this.olxUrl = olxUrl;
this.hrefResutls = hrefResutls;
}
async indexWithPagination(pageNumber = 1) {
const pageNr = this.olxUrl.url.match(/\d+$/);
const indexers = this.prepareIndexers(pageNumber ? [pageNumber] : pageNr);
try {
return Promise.map(indexers.indexers, function(indexer) {
return indexer.indexPage(pageNumber);
}).then(async results => {
let hasResults = false;
results.forEach(result => {
if (!hasResults) {
hasResults = result.hasResults;
}
});
if (!hasResults) {
const singlePageIndexers = this.prepareHrefIndexers(results);
if (singlePageIndexers.length === 0) {
return [];
}
return Promise.map(singlePageIndexers, function(indexer) {
return indexer.indexSingle();
}).then(async results => {
return results;
});
} else {
const newResults = await this.indexWithPagination(
results[0].pageNumber + 5
);
const singlePageIndexers = this.prepareHrefIndexers(results);
const newerResults = await Promise.map(singlePageIndexers, function(
indexer
) {
return indexer.indexSingle();
}).then(async results => {
return results;
});
Array.prototype.push.apply(newResults, newerResults);
return newResults;
}
});
} catch (e) {
console.error("Error has accured", e);
}
}
prepareIndexers(pageNr) {
const indexers = [];
let lastPageNumber;
if (pageNr) {
for (
let index = Number(pageNr[0]);
index <= Number(pageNr[0]) + 5;
index++
) {
lastPageNumber = index;
const newOlxUrl = {
url: this.olxUrl.url.replace(/\d+$/, "") + index,
email: this.olxUrl.email,
uuid: this.olxUrl.uuid,
hrefs: this.olxUrl.hrefs
};
indexers.push(new Indexer(newOlxUrl));
}
} else {
for (let index = 1; index <= 5; index++) {
lastPageNumber = index;
const newOlxUrl = {
url: this.olxUrl.url + index,
email: this.olxUrl.email,
uuid: this.olxUrl.uuid,
hrefs: this.olxUrl.hrefs
};
indexers.push(new Indexer(newOlxUrl));
}
}
return {
indexers: indexers,
lastPageNumber: lastPageNumber
};
}
prepareHrefIndexers(results) {
const indexers = [];
if (!Array.isArray(results)) {
results.hrefs.forEach(href => {
const newOlxUrl = {
url: href,
email: results.olxUrl.email,
uuid: results.olxUrl.uuid,
hrefs: this.olxUrl.hrefs
};
indexers.push(new Indexer(newOlxUrl));
});
} else {
results.forEach(result => {
if (result !== null && result.hasOwnProperty("hrefs")) {
result.hrefs.forEach(href => {
const newOlxUrl = {
url: href,
email: result.olxUrl.email,
uuid: result.olxUrl.uuid,
hrefs: this.olxUrl.hrefs
};
indexers.push(new Indexer(newOlxUrl));
});
}
});
}
return indexers;
}
async indexPage(pageNumber) {
try {
const res = await fetch(this.olxUrl.url);
const body = await res.text();
const $ = cheerio.load(body);
const hrefs = [];
let hasResults = false;
$("#rezultatipretrage")
.find(".listitem")
.each((i, elem) => {
hasResults = true;
const href = $(elem)
.find("a")
.first()
.attr("href");
hrefs.push(href);
});
return {
hrefs: hrefs,
hasResults: hasResults,
pageNumber: pageNumber,
olxUrl: this.olxUrl
};
} catch (e) {
console.error("Exception caught:" + e);
}
}
async indexSingle() {
try {
if (this.olxUrl.url === undefined) {
return {};
}
// if (global.hrefs) {
if (
this.olxUrl.hrefs[this.olxUrl.uuid] &&
this.olxUrl.hrefs[this.olxUrl.uuid].includes(this.olxUrl.url)
) {
return null;
}
// }
const res = await fetch(this.olxUrl.url);
const body = await res.text();
const $ = cheerio.load(body);
const title = $("#naslovartikla")
.text()
.trim();
const realEstateType = $(
"#artikal_glavni_div > div.artikal_lijevo > div:nth-child(3) > div > span:nth-child(3) > a > span"
).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 gardenSize = $(
"#dodatnapolja1 > div:nth-child(6) > div.df2"
).text();
const location = $(
"#artikal_glavni_div > div.artikal_lijevo > div.op.pop.mobile-lokacija"
).attr("data-content");
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 parsePrice = price => parseFloat(price.replace(".", ""));
if (matches && matches.length >= 3) {
lat = matches[1];
lng = matches[2];
}
const parsedPrice = parsePrice(price);
const locationArray =
location && location.length > 0 ? location.split(",") : [];
const region = locationArray.length > 0 ? locationArray[0] : "";
const municipality = locationArray.length > 1 ? locationArray[1] : "";
const data = {
realEstateType: this.getCategoryId(realEstateType),
email: this.olxUrl.email,
uuid: this.olxUrl.uuid,
olxId: olxId,
url: this.olxUrl.url,
title,
price: isNaN(parsedPrice) ? 0 : parsedPrice,
size: parseFloat(size),
gardenSize: isNaN(parseFloat(gardenSize)) ? 0 : parseFloat(gardenSize),
address,
region,
municipality,
time,
shortDescription: descriptions.first().text(),
longDescription: descriptions.last().text(),
lat,
lng,
loc: [parseFloat(lat), parseFloat(lng)]
};
return data;
} catch (e) {
console.error("Exception caught: " + e.message);
}
return null;
}
getCategoryId(category) {
switch (category) {
case "Stanovi":
return "stan";
case "Vikendice":
return "vikendica";
case "Kuće":
return "kuca";
default:
return "";
}
}
}

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@@ -1,77 +0,0 @@
const Promise = require("bluebird");
const OlxCrawler = require("../helpers/crawlers/olxClawler");
const db = require("../models/index");
const { allMarketAlerts } = require("../helpers/db/dbHelper");
async function crawlAll() {
try {
const marketAlertsFromDb = await allMarketAlerts(true);
const hrefs = [];
marketAlertsFromDb.map(marketAlert => {
if (hrefs[marketAlert.request] === undefined) {
hrefs[marketAlert.request] = [];
}
hrefs[marketAlert.request].push(marketAlert.url);
});
const olxCrawler = new OlxCrawler(hrefs);
const crawlers = [olxCrawler];
return Promise.map(crawlers, function(crawler) {
return crawler.crawl();
}).then(async results => {
try {
const marketAlertsFromDb = await allMarketAlerts(false, true);
const marketAlerts = [];
const mergedResults = [].concat.apply([], results);
for (const result of mergedResults) {
marketAlerts.push({
url: result.url,
realestateOrigin: "OLX",
originId: 1,
size: result.size,
price: result.price,
email: result.email,
request: result.uuid,
municipality: result.municipality,
region: result.region,
gardenSize: isNaN(result.gardenSize) ? 0 : result.gardenSize,
realEstateType: result.realEstateType,
title: result.title,
notified: false,
hasLocation: result.hasLocation
});
}
try {
const filteredMarketAlerts = marketAlerts.filter(
elem =>
!marketAlertsFromDb.find(({ url, request }) => {
return elem.url === url && elem.request === request;
})
);
await db.MarketAlert.bulkCreate(filteredMarketAlerts);
} catch (e) {
console.log(
"CRAWLER SERVICE: Could not bulkCreate marketalers reason: ",
e
);
}
} catch (e) {
console.log(
"CRAWLER SERVICE: Error crawling. Trying next crawler! ",
e
);
}
});
} catch (e) {
console.error("CRAWLER SERVICE:could not fetch marketalerts ", e);
}
}
module.exports = crawlAll;

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@@ -10,7 +10,8 @@
"migrate": "cd app && npx sequelize db:migrate",
"setup": "docker build -t marketalerts . && docker run -e POSTGRES_USER=docker -e POSTGRES_PASSWORD=docker -e POSTGRES_DB=marketalerts --name pg_marketalerts -d -p 5432:5432 marketalerts && sleep 4 && npm run migrate",
"docker-start": "docker start pg_marketalerts",
"docker-stop": "docker stop pg_marketalerts"
"docker-stop": "docker stop pg_marketalerts",
"crawl": "cd app/crawler && node crawl.js"
},
"repository": {
"type": "git",