adding or replacing sort params for provider urls when necessary

lib/FredyRuntime.js

@@ -4,6 +4,7 @@ const { setKnownListings, getKnownListings } = require('./services/storage/listi
 const notify = require('./notification/notify');
 const xray = require('./services/scraper');
 const scrapingAnt = require('./services/scrapingAnt');
+const urlModifier = require('./services/queryStringMutator');
 
 class FredyRuntime {
   /**
@@ -24,7 +25,8 @@ class FredyRuntime {
 
   execute() {
     return (
-      Promise.resolve(this._providerConfig.url)
+      //modify the url to make sure search order is correctly set
+      Promise.resolve(urlModifier(this._providerConfig.url, this._providerConfig.sortByDateParam))
         //scraping the site and try finding new listings
         .then(this._getListings.bind(this))
         //bring them in a proper form (dictated by the provider)

lib/provider/einsAImmobilien.js

@@ -22,6 +22,7 @@ function applyBlacklist(o) {
 const config = {
   url: null,
   crawlContainer: '.tabelle',
+  sortByDateParam: 'sort_type=newest',
   crawlFields: {
     id: '.inner_object_data input[name="marker_objekt_id"]@value | int',
     price: '.tabelle .inner_object_data .single_data_price | removeNewline | trim',

lib/provider/immonet.js

@@ -24,6 +24,7 @@ function applyBlacklist(o) {
 const config = {
   url: null,
   crawlContainer: '#result-list-stage .item',
+  sortByDateParam: 'sortby=19',
   crawlFields: {
     id: '@id',
     price: 'div[id*="selPrice_"] | trim',

lib/provider/immoscout.js

@@ -20,6 +20,7 @@ function applyBlacklist(o) {
 const config = {
   url: null,
   crawlContainer: '#resultListItems li.result-list__listing',
+  sortByDateParam: 'sorting=2',
   crawlFields: {
     id: '.result-list-entry@data-obid | int',
     price: '.result-list-entry .result-list-entry__criteria .grid-item:first-child dd | removeNewline | trim',

lib/provider/immowelt.js

@@ -16,6 +16,7 @@ function applyBlacklist(o) {
 const config = {
   url: null,
   crawlContainer: "div[class^='EstateItem-']",
+  sortByDateParam: 'sd=DESC&sf=TIMESTAMP',
   crawlFields: {
     id: 'a@id',
     price: "div[class^='KeyFacts-'] [data-test='price'] | removeNewline | trim",

lib/provider/kleinanzeigen.js

@@ -21,6 +21,8 @@ function applyBlacklist(o) {
 const config = {
   url: null,
   crawlContainer: '#srchrslt-adtable .ad-listitem ',
+  //sort by date is standard oO
+  sortByDateParam: null,
   crawlFields: {
     id: '.aditem@data-adid | int',
     price: '.aditem-main--middle--price | removeNewline | trim',

lib/provider/neubauKompass.js

@@ -13,6 +13,7 @@ function applyBlacklist(o) {
 const config = {
   url: null,
   crawlContainer: '.nbk-container >div article',
+  sortByDateParam: 'Sortierung=Id&Richtung=DESC',
   crawlFields: {
     id: '@id',
     title: 'a.nbk-truncate@title | removeNewline | trim',

lib/provider/wgGesucht.js

@@ -16,6 +16,7 @@ function applyBlacklist(o) {
 const config = {
   url: null,
   crawlContainer: '#main_column .wgg_card',
+  sortByDateParam: 'sort_column=0&sort_order=0',
   crawlFields: {
     id: '@data-id',
     details: '.row .noprint .col-xs-11 |removeNewline |trim',

lib/services/queryStringMutator.js

@@ -0,0 +1,22 @@
+const queryString = require('query-string');
+
+/**
+ * for Fredy, it is important to sort search results by date, starting with the latest listing. if it is not sorted, we
+ * might never actually find the newest results, no matter how many pages we crawl.
+ * It has been written in the documentation, but obviously nobody reads docu theses days which is why it's been done
+ * automagically now.
+ *
+ * @param _url actual provider url containing the searchParams
+ * @param sortByDateParam param(s) indicating the correct sort order
+ * @returns {`${string}?${string}`} correctly formatted url
+ */
+module.exports = (_url, sortByDateParam) => {
+  //if no mutation is necessary, just return the original url
+  if (sortByDateParam == null) {
+    return _url;
+  }
+
+  const original = queryString.parseUrl(_url);
+  const mutate = queryString.parse(sortByDateParam);
+  return `${original.url}?${queryString.stringify({ ...original.query, ...mutate })}`;
+};