Implement simple pagination

app/Contracts/UserRepository.php

@@ -10,6 +10,8 @@ interface UserRepository
 
     public function getUserById($id): PromiseInterface;
 
+    public function paginateUsers(int $perPage, int $currentPage): PromiseInterface;
+
     public function getUserByToken(string $authToken): PromiseInterface;
 
     public function storeUser(array $data): PromiseInterface;

app/Server/Http/Controllers/Admin/GetUsersController.php

@@ -21,10 +21,10 @@ class GetUsersController extends AdminController
     public function handle(Request $request, ConnectionInterface $httpConnection)
     {
         $this->userRepository
-            ->getUsers()
+            ->paginateUsers(20, (int) $request->get('page', 1))
-            ->then(function ($users) use ($httpConnection) {
+            ->then(function ($paginated) use ($httpConnection) {
                 $httpConnection->send(
-                    respond_json(['users' => $users])
+                    respond_json(['paginated' => $paginated])
                 );
 
                 $httpConnection->close();

app/Server/Http/Controllers/Admin/ListUsersController.php

@@ -21,10 +21,10 @@ class ListUsersController extends AdminController
     public function handle(Request $request, ConnectionInterface $httpConnection)
     {
         $this->userRepository
-            ->getUsers()
+            ->paginateUsers(20, (int) $request->get('page', 1))
-            ->then(function ($users) use ($httpConnection) {
+            ->then(function ($paginated) use ($httpConnection) {
                 $httpConnection->send(
-                    respond_html($this->getView($httpConnection, 'server.users.index', ['users' => $users]))
+                    respond_html($this->getView($httpConnection, 'server.users.index', ['paginated' => $paginated]))
                 );
 
                 $httpConnection->close();

app/Server/UserRepository/DatabaseUserRepository.php

@@ -31,6 +31,35 @@ class DatabaseUserRepository implements UserRepository
         return $deferred->promise();
     }
 
+    public function paginateUsers(int $perPage, int $currentPage): PromiseInterface
+    {
+        $deferred = new Deferred();
+
+        $this->database
+            ->query('SELECT * FROM users ORDER by created_at DESC LIMIT :limit OFFSET :offset', [
+                'limit' => $perPage + 1,
+                'offset' => $currentPage < 2 ? 0 :  ($currentPage - 1) * $perPage,
+            ])
+            ->then(function (Result $result) use ($deferred, $perPage, $currentPage) {
+                if(count($result->rows) == $perPage + 1) {
+                    array_pop($result->rows);
+                    $nextPage = $currentPage + 1;
+                }
+
+                $paginated = [
+                    'users' => $result->rows,
+                    'current_page' => $currentPage,
+                    'per_page' => $perPage,
+                    'next_page' => $nextPage ?? null,
+                    'previous_page' => $currentPage > 1 ? $currentPage - 1 : null,
+                ];
+
+                $deferred->resolve($paginated);
+            });
+
+        return $deferred->promise();
+    }
+
     public function getUserById($id): PromiseInterface
     {
         $deferred = new Deferred();

resources/views/server/users/index.twig

@@ -75,6 +75,27 @@
                 </tr>
                 </tbody>
             </table>
+
+            <div class="flex items-center justify-end text-gray-900 p-4" v-if="paginated.current_page > 0">
+                <button
+                    :disabled="paginated.previous_page == null"
+                    v-on:click="getUsers(paginated.previous_page)"
+                    type="button"
+                    :class="(paginated.previous_page == null ? 'opacity-50 cursor-not-allowed' : '') + ' mr-3 py-2 px-4 border border-gray-300 rounded-md text-sm leading-5 font-medium text-gray-700 hover:text-gray-500 focus:outline-none focus:border-blue-300 focus:shadow-outline-blue active:bg-gray-50 active:text-gray-800 transition duration-150 ease-in-out'"
+                >
+                    Previous
+                </button>
+
+                <button
+                    :disabled="paginated.next_page == null"
+                    v-on:click="getUsers(paginated.next_page)"
+                    type="button"
+                    :class="(paginated.next_page == null ? 'opacity-50 cursor-not-allowed' : '') + ' py-2 px-4 border border-gray-300 rounded-md text-sm leading-5 font-medium text-gray-700 hover:text-gray-500 focus:outline-none focus:border-blue-300 focus:shadow-outline-blue active:bg-gray-50 active:text-gray-800 transition duration-150 ease-in-out'"
+                >
+                    Next
+                </button>
+            </div>
+
             <div class="flex items-center justify-center text-gray-900 p-4" v-else>
                 <span class="text-xl">The expose server does not have any users yet.</span>
             </div>
@@ -94,10 +115,25 @@
                         name: '',
                         errors: {},
                     },
-                    users: {{ users|json_encode|raw }}
+                    paginated: {{ paginated|json_encode|raw }}
+                },
+
+                computed: {
+                    users : function() {
+                        return this.paginated.users;
+                    }
                 },
 
                 methods: {
+                    getUsers(page) {
+                        fetch('/api/users?page=' + page)
+                            .then((response) => {
+                                return response.json();
+                            }).then((data) => {
+                                this.paginated = data.paginated;
+                            });
+                    },
+
                     deleteUser(user) {
                         fetch('/api/users/' + user.id, {
                             method: 'DELETE',