✨ Add filter option in user using key/value

src/controllers/user.js

@@ -3,6 +3,7 @@ const {
   dataInMemory: frozenData,
   getMultiObjectSubset,
   getObjectSubset,
+  getNestedValue,
 } = require('../utils/util');
 
 const controller = {};
@@ -58,6 +59,32 @@ controller.searchUsers = ({ limit, skip, select, q: searchQuery }) => {
   return result;
 };
 
+// filter users
+controller.filterUsers = ({ limit, skip, select, key, value }) => {
+  let [...users] = frozenData.users.filter(u => {
+    const val = getNestedValue(u, key);
+    return val && val.toString() === value;
+  });
+
+  const total = users.length;
+
+  if (skip > 0) {
+    users = users.slice(skip);
+  }
+
+  if (users.length > limit) {
+    users.length = limit;
+  }
+
+  if (select) {
+    users = getMultiObjectSubset(users, select);
+  }
+
+  const result = { users, total, skip, limit: users.length };
+
+  return result;
+};
+
 // get user by id
 controller.getUserById = ({ id, select }) => {
   let { ...user } = verifyUserHandler(id);

src/middleware/cleanRequest.js

@@ -14,7 +14,7 @@ const cleanRequest = (req, res, next) => {
     const options = {};
     req._options = options;
 
-    const { limit = 30, skip = 0, q } = req.query;
+    const { limit = 30, skip = 0, q, key, value } = req.query;
     let { select } = req.query;
 
     if (!isNumber(limit)) {
@@ -40,6 +40,8 @@ const cleanRequest = (req, res, next) => {
     options.skip = skip;
     options.select = select;
     options.q = searchQuery;
+    options.key = key;
+    options.value = value;
 
     next();
   } catch (e) {

src/routes/user.js

@@ -9,6 +9,7 @@ const {
   addNewUser,
   updateUserById,
   deleteUserById,
+  filterUsers,
 } = require('../controllers/user');
 const { verifyUserHandler } = require('../helpers');
 
@@ -17,11 +18,16 @@ router.get('/', (req, res) => {
   res.send(getAllUsers({ ...req._options }));
 });
 
-// search user
+// search users
 router.get('/search', (req, res) => {
   res.send(searchUsers({ ...req._options }));
 });
 
+// filter users
+router.get('/filter', (req, res) => {
+  res.send(filterUsers({ ...req._options }));
+});
+
 // get user by id
 router.get('/:id', (req, res) => {
   const { id } = req.params;

src/utils/util.js

@@ -193,4 +193,8 @@ utils.deepFreeze = function(obj) {
   return obj;
 };
 
+utils.getNestedValue = (obj, keys) => {
+  return keys.split('.').reduce((o, k) => (o || {})[k], obj);
+};
+
 module.exports = utils;

views/docs-users.ejs

@@ -250,6 +250,63 @@ fetch('https://dummyjson.com/users/search?q=John')
           </blockquote>
         </div>
 
+        <div class="sub-section">
+          <h3 id="filter">
+            <a href="#filter" class="no-link">Filter users</a>
+          </h3>
+          <p>
+            <small>
+              <i class="bx bx-right-arrow bx-xs"></i>
+              You can pass key (nested keys with ".") and value as params to
+              filter users. (key and value are case-sensitive)
+            </small>
+
+            <br />
+
+            <small>
+              <i class="bx bx-bulb bx-xs"></i>
+              "limit", "skip" and "select" works too.
+            </small>
+          </p>
+
+          <blockquote>
+            <pre>
+              <code class="language-js">
+fetch('https://dummyjson.com/users/filter?key=hair.color&value=Brown')
+.then(res => res.json())
+.then(console.log);
+            </code>
+           </pre>
+          </blockquote>
+
+          <a class="button" onclick="toggleOutput(event)">
+            Show output
+          </a>
+
+          <blockquote>
+            <pre class="result hidden">
+              <code class="language-json">
+{
+  "users": [
+    {
+      "firstName": "Demetrius",
+      "hair": {
+        "color": "Brown", // filter matched hair color
+      },
+      "id": 9,
+      "lastName": "Corkery"
+      // rest user data
+    }
+  ],
+  "total": 26,
+  "skip": 0,
+  "limit": 26
+}
+              </code>
+            </pre>
+          </blockquote>
+        </div>
+
         <div class="sub-section">
           <h3 id="limit_skip">
             <a href="#limit_skip" class="no-link">Limit and skip users</a>

views/partials/docs-side-nav.ejs

@@ -167,6 +167,12 @@
       </a>
     </li>
 
+    <li>
+      <a href="/docs/users/#filter">
+        Filter users
+      </a>
+    </li>
+
     <li>
       <a href="/docs/users/#limit_skip">
         Limit & Skip users