Initial Version

server/utils/apiFeatures.js

@@ -0,0 +1,48 @@
+class APIFeatures {
+    constructor(query, queryStr) {
+        this.query = query;
+        this.queryStr = queryStr;
+    }
+
+    search() {
+        const keyword = this.queryStr.keyword
+            ? {
+                  name: {
+                      $regex: this.queryStr.keyword,
+                      $options: "i",
+                  },
+              }
+            : {};
+
+        this.query = this.query.find({ ...keyword });
+        return this;
+    }
+
+    filter() {
+        const queryCopy = { ...this.queryStr };
+
+        // Removing fields from the query
+        const removeFields = ["keyword", "limit", "page"];
+        removeFields.forEach((el) => delete queryCopy[el]);
+
+        // Advance filter for price, ratings etc
+        let queryStr = JSON.stringify(queryCopy);
+        queryStr = queryStr.replace(
+            /\b(gt|gte|lt|lte)\b/g,
+            (match) => `$${match}`
+        );
+
+        this.query = this.query.find(JSON.parse(queryStr));
+        return this;
+    }
+
+    pagination(resPerPage) {
+        const currentPage = Number(this.queryStr.page) || 1;
+        const skip = resPerPage * (currentPage - 1);
+
+        this.query = this.query.limit(resPerPage).skip(skip);
+        return this;
+    }
+}
+
+module.exports = APIFeatures;