create new crawler and Postgres saver

app/crawler/crawlerConfig.js

@@ -0,0 +1,32 @@
+"use strict";
+require("dotenv").config({ path: "../../.env" });
+const { CRAWLER_AD_TYPE, AD_CATEGORY } = require("../common/enums");
+
+const crawlerAdType =
+  process.env.OLX_CRAWLER_AD_TYPE !== undefined
+    ? CRAWLER_AD_TYPE[process.env.OLX_CRAWLER_AD_TYPE]
+    : null;
+
+const parsedCrawlerAdCategories =
+  process.env.OLX_CRAWLER_AD_CATEGORIES !== undefined
+    ? process.env.OLX_CRAWLER_AD_CATEGORIES.split(",").map(category =>
+        category.trim()
+      )
+    : ["CATEGORY_FLAT", "CATEGORY_HOUSE"];
+
+const transformedCrawlerAdCategories = parsedCrawlerAdCategories
+  .map(categoryName => AD_CATEGORY[categoryName])
+  .filter(category => !!category);
+
+const OLX_CONFIG = {
+  OLX_START_PAGE: parseInt(process.env.OLX_START_PAGE) || 1,
+  OLX_END_PAGE: parseInt(process.env.OLX_END_PAGE) || 10,
+  OLX_MAX_RESULTS_PER_PAGE:
+    parseInt(process.env.OLX_MAX_RESULTS_PER_PAGE) || 50,
+  OLX_CRAWLER_AD_TYPE: crawlerAdType || CRAWLER_AD_TYPE.NONE,
+  OLX_CRAWLER_AD_CATEGORIES: transformedCrawlerAdCategories
+};
+
+module.exports = {
+  OLX_CONFIG
+};