*/ protected array $resultModifiers = []; /** * @var array */ protected array $filterOperators = [ 'eq' => '=', 'ne' => '!=', 'gt' => '>', 'lt' => '<', 'gte' => '>=', 'lte' => '<=', 'like' => 'like', ]; /** * ListingResponseBuilder constructor. * The given fields will be forced visible within the model results. */ public function __construct(Builder $query, Request $request, array $fields) { $this->query = $query; $this->request = $request; $this->fields = $fields; } /** * Get the response from this builder. */ public function toResponse(): JsonResponse { $filteredQuery = $this->filterQuery($this->query); $total = $filteredQuery->count(); $data = $this->fetchData($filteredQuery)->each(function ($model) { foreach ($this->resultModifiers as $modifier) { $modifier($model); } }); return response()->json([ 'data' => $data, 'total' => $total, ]); } /** * Add a callback to modify each element of the results. * * @param (callable(Model): void) $modifier */ public function modifyResults(callable $modifier): void { $this->resultModifiers[] = $modifier; } /** * Fetch the data to return within the response. */ protected function fetchData(Builder $query): Collection { $query = $this->countAndOffsetQuery($query); $query = $this->sortQuery($query); return $query->get($this->fields); } /** * Apply any filtering operations found in the request. */ protected function filterQuery(Builder $query): Builder { $query = clone $query; $requestFilters = $this->request->get('filter', []); if (!is_array($requestFilters)) { return $query; } $queryFilters = collect($requestFilters)->map(function ($value, $key) { return $this->requestFilterToQueryFilter($key, $value); })->filter(function ($value) { return !is_null($value); })->values()->toArray(); return $query->where($queryFilters); } /** * Convert a request filter query key/value pair into a [field, op, value] where condition. */ protected function requestFilterToQueryFilter($fieldKey, $value): ?array { $splitKey = explode(':', $fieldKey); $field = $splitKey[0]; $filterOperator = $splitKey[1] ?? 'eq'; if (!in_array($field, $this->fields)) { return null; } if (!in_array($filterOperator, array_keys($this->filterOperators))) { $filterOperator = 'eq'; } $queryOperator = $this->filterOperators[$filterOperator]; return [$field, $queryOperator, $value]; } /** * Apply sorting operations to the query from given parameters * otherwise falling back to the first given field, ascending. */ protected function sortQuery(Builder $query): Builder { $query = clone $query; $defaultSortName = $this->fields[0]; $direction = 'asc'; $sort = $this->request->get('sort', ''); if (strpos($sort, '-') === 0) { $direction = 'desc'; } $sortName = ltrim($sort, '+- '); if (!in_array($sortName, $this->fields)) { $sortName = $defaultSortName; } return $query->orderBy($sortName, $direction); } /** * Apply count and offset for paging, based on params from the request while falling * back to system defined default, taking the max limit into account. */ protected function countAndOffsetQuery(Builder $query): Builder { $query = clone $query; $offset = max(0, $this->request->get('offset', 0)); $maxCount = config('api.max_item_count'); $count = $this->request->get('count', config('api.default_item_count')); $count = max(min($maxCount, $count), 1); return $query->skip($offset)->take($count); } }