Check user count to prevent more than one registered user

app/Http/Controllers/UserController.php

@@ -5,6 +5,7 @@
 use App\User;
 use Validator;
 use Illuminate\Http\Request;
+use Illuminate\Support\Facades\DB;
 use App\Http\Controllers\Controller;
 use Illuminate\Support\Facades\Auth;
 
@@ -56,6 +57,20 @@ public function logout()
     }
 
 
+    /**
+     * check if a user exists
+     * @param  Request $request [description]
+     * @return json
+     */
+    public function checkUser()
+    {
+
+        $count = DB::table('users')->count();
+
+        return response()->json(['userCount' => $count], 200);
+    }
+
+
     /**
      * register new user
      * @param  Request $request [description]
@@ -63,6 +78,14 @@ public function logout()
      */
     public function register(Request $request)
     {
+
+        // check if a user already exists
+        $count = DB::table('users')->count();
+
+        if( $count > 0 ) {
+            return response()->json(['error' => __('already_one_user_registered')], 400);
+        }
+
         $validator = Validator::make($request->all(), [
             'name' => 'required',
             'email' => 'required|email',

resources/js/app.js

@@ -59,6 +59,12 @@ const router = new VueRouter({
             name: 'edit',
             component: Edit,
         },
+        {
+            path: '/flooded',
+            name: 'flooded',
+            component: NotFound,
+            props: true
+        },
         {
             path: '/error',
             name: 'GenericError',

resources/js/views/Error.vue

@@ -5,6 +5,12 @@
                 <p class="error-404"></p>
                 <p>{{ $t('errors.resource_not_found') }}<router-link :to="{ name: 'accounts' }" class="is-text has-text-white">{{ $t('errors.refresh') }}</router-link></p>
             </div>
+            <div v-else-if="$route.name == 'flooded'">
+                <p class="error-generic"></p>
+                <p>{{ $t('errors.already_one_user_registered') }}<br>
+                    {{ $t('errors.cannot_register_more_user') }}<br><br>
+                    {{ $t('errors.please') }}<router-link :to="{ name: 'accounts' }" class="is-text has-text-white">{{ $t('auth.sign_in') }}</router-link></p>
+            </div>
             <div v-else>
                 <p class="error-generic"></p>
                 <p>{{ $t('errors.error_occured') }}<router-link :to="{ name: 'accounts' }" class="is-text has-text-white">{{ $t('errors.refresh') }}</router-link></p>
@@ -50,14 +56,6 @@
                 this.$router.push({name: 'accounts' });
             });
 
-        },
-        
-        beforeRouteEnter (to, from, next) {
-            if ( ! localStorage.getItem('jwt')) {
-                return next('login')
-            }
-
-            next()
         }
     }
 

resources/js/views/Register.vue

@@ -38,6 +38,10 @@
                         </div>
                     </div>
                 </form>
+                <br />
+                <span class="tag is-danger" v-if="errorMessage">
+                    {{ errorMessage }}
+                </span>
             </div>
         </div>
         <div class="columns is-mobile is-centered">
@@ -58,10 +62,25 @@
                 email : '',
                 password : '',
                 password_confirmation : '',
-                errors: {}
+                errors: {},
+                errorMessage: ''
             }
         },
 
+        created: function() {
+            // we check if a user account already exists
+            axios.post('api/checkuser')
+            .then(response => {
+                if( response.data.userCount > 0) {
+                    this.errorMessage = this.$t('errors.already_one_user_registered') + ' ' + this.$t('errors.cannot_register_more_user')
+                    this.$router.push({ name: 'flooded' });
+                }
+            })
+            .catch(error => {
+                this.$router.push({ name: 'error', params: { err: error.response.message } });
+            });
+        },
+
         methods : {
             handleSubmit(e) {
                 e.preventDefault()

resources/js/vue-i18n-locales.generated.js

@@ -14,7 +14,7 @@ export default {
                 "email": "Email",
                 "password": "Password",
                 "confirm_password": "Confirm password",
-                "dont_have_account_yet": "Don't have an account yet?",
+                "dont_have_account_yet": "Don't have your account yet?",
                 "already_register": "Already registered?",
                 "passwords_do_not_match": "Passwords do not match"
             }
@@ -25,7 +25,10 @@ export default {
         "errors": {
             "resource_not_found": "Resource not found, please ",
             "error_occured": "An error occured, please ",
+            "already_one_user_registered": "There is already a registered user.",
+            "cannot_register_more_user": "You cannot register more than one user.",
             "refresh": "refresh",
+            "please": "Please ",
             "response": {
                 "no_valid_totp": "No valid TOTP resource in this QR code"
             }

resources/lang/en/auth.php

@@ -26,7 +26,7 @@
         'email' => 'Email',
         'password' => 'Password',
         'confirm_password' => 'Confirm password',
-        'dont_have_account_yet' => 'Don\'t have an account yet?',
+        'dont_have_account_yet' => 'Don\'t have your account yet?',
         'already_register' => 'Already registered?',
         'passwords_do_not_match' => 'Passwords do not match',
     ]

resources/lang/en/errors.php

@@ -15,7 +15,10 @@
 
     'resource_not_found' => 'Resource not found, please ',
     'error_occured' => 'An error occured, please ',
+    'already_one_user_registered' => 'There is already a registered user.',
+    'cannot_register_more_user' => 'You cannot register more than one user.',
     'refresh' => 'refresh',
+    'please' => 'Please ',
     'response' => [
         'no_valid_totp' => 'No valid TOTP resource in this QR code',
     ]

routes/api.php

@@ -14,6 +14,7 @@
 */
 
 Route::post('login', 'UserController@login');
+Route::post('checkuser', 'UserController@checkUser');
 Route::post('register', 'UserController@register');
 
 Route::group(['middleware' => 'auth:api'], function(){