Added API to query users by location (only for users who have defined their location)

extend.php

@@ -18,7 +18,20 @@ use Flarum\Api\Serializer\UserSerializer;
 use Flarum\Extend;
 use Flarum\User\Event\Saving;
 use Flarum\Api\Event\Serializing;
+use Flarum\User\Filter\UserFilterer;
+use Flarum\Filter\FilterState;
+use Flarum\Query\QueryCriteria;
 
+class UserLocationFilterMutator
+{
+    public function __invoke(FilterState $filterState, QueryCriteria $queryCriteria)
+    {
+        if($queryCriteria->mustHaveLocation)
+        {
+            $filterState->getQuery()->where('location_latitude', '!=', 'null');
+        }
+    }
+}
 
 return [
     (new Extend\Frontend('forum'))
@@ -37,5 +50,11 @@ return [
     (new Extend\Settings)->serializeToForum('justoverclock-users-map-location.mapBox-api-key', 'justoverclock-users-map-location.mapBox-api-key'),
 	
 	(new Extend\Frontend('forum'))
-        ->route('/global-map', 'justoverclock.global-map')
+        ->route('/global-map', 'justoverclock.global-map'),
+    
+    (new Extend\Filter(UserFilterer::class))
+        ->addFilterMutator(UserLocationFilterMutator::class),
+    
+    (new Extend\Routes('api'))
+        ->get('/user-locations', 'user-locations.index', Api\Controller\ListUserLocationsController::class)
 ];

src/Api/Controller/ListUserLocationsController.php

@@ -0,0 +1,100 @@
+<?php
+
+namespace Justoverclock\UsersMapLocation\Api\Controller;
+
+use Flarum\Api\Controller\AbstractListController;
+use Flarum\Http\RequestUtil;
+use Flarum\Http\UrlGenerator;
+use Psr\Http\Message\ServerRequestInterface;
+use Tobscure\JsonApi\Document;
+use Justoverclock\UsersMapLocation\Api\Serializer\UserLocationSerializer;
+use Flarum\User\User;
+use Flarum\Query\QueryCriteria;
+use Flarum\User\Filter\UserFilterer;
+use Flarum\User\Search\UserSearcher;
+
+use Illuminate\Database\Eloquent\Builder;
+
+class ListUserLocationsController extends AbstractListController
+{
+	/**
+	 * {@inheritdoc}
+	 */
+	public $serializer = UserLocationSerializer::class;
+	
+	/**
+	 * @var UserFilterer
+	 */
+	protected $filterer;
+
+	/**
+	 * @var UserSearcher
+	 */
+	protected $searcher;
+
+	/**
+	 * @var UrlGenerator
+	 */
+	protected $url;
+
+	/**
+	 * @param UserLocationFilterer $filterer
+	 * @param UserSearcher $searcher
+	 * @param UrlGenerator $url
+	 */
+	public function __construct(UserFilterer $filterer, UserSearcher $searcher, UrlGenerator $url)
+	{
+		$this->filterer = $filterer;
+		$this->searcher = $searcher;
+		$this->url = $url;
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	protected function data(ServerRequestInterface $request, Document $document)
+	{
+		// See https://docs.flarum.org/extend/api.html#api-endpoints for more information.
+
+		$actor = RequestUtil::getActor($request);
+		
+		$actor->assertCan('searchUsers');
+
+		if (! $actor->hasPermission('user.viewLastSeenAt')) {
+			// If a user cannot see everyone's last online date, we prevent them from sorting by it
+			// Otherwise this sort field would defeat the privacy setting discloseOnline
+			// We use remove instead of add so that extensions can still completely disable the sort using the extender
+			$this->removeSortField('lastSeenAt');
+		}
+
+		$filters = $this->extractFilter($request);
+		$sort = $this->extractSort($request);
+		$sortIsDefault = $this->sortIsDefault($request);
+
+		$limit = $this->extractLimit($request);
+		$offset = $this->extractOffset($request);
+		$include = $this->extractInclude($request);
+
+		$criteria = new QueryCriteria($actor, $filters, $sort, $sortIsDefault);
+		$criteria->mustHaveLocation = true;
+		if (array_key_exists('q', $filters)) {
+			$results = $this->searcher->search($criteria, $limit, $offset);
+		} else {
+			$results = $this->filterer->filter($criteria, $limit, $offset);
+		}
+
+		$document->addPaginationLinks(
+			$this->url->to('api')->route('user-locations.index'),
+			$request->getQueryParams(),
+			$offset,
+			$limit,
+			$results->areMoreResults() ? null : 0
+		);
+		
+		$results = $results->getResults();
+
+		$this->loadRelations($results, $include, $request);
+
+		return $results;
+	}
+}

src/Api/Serializer/UserLocationSerializer.php

@@ -0,0 +1,39 @@
+<?php
+
+namespace Justoverclock\UsersMapLocation\Api\Serializer;
+
+use Flarum\Api\Serializer\AbstractSerializer;
+use Flarum\User\User;
+use InvalidArgumentException;
+
+class UserLocationSerializer extends AbstractSerializer
+{
+	/**
+	 * {@inheritdoc}
+	 */
+	protected $type = 'users';
+
+	/**
+	 * {@inheritdoc}
+	 *
+	 * @param User $model
+	 * @throws InvalidArgumentException
+	 */
+	protected function getDefaultAttributes($model)
+	{
+		if (! ($model instanceof User)) {
+			throw new InvalidArgumentException(
+				get_class($this).' can only serialize instances of '.User::class
+			);
+		}
+
+		// See https://docs.flarum.org/extend/api.html#serializers for more information.
+
+		return [
+			'username' => $model->username,
+			'displayName' => $model->display_name,
+			'location_longitude' => $model->location_longitude,
+			'location_latitude' => $model->location_latitude,
+		];
+	}
+}