Merge pull request #23 from ukfast/allow_null_sort_order_to_be_changed

Allow null sort order to be changed

README.md

@@ -89,6 +89,13 @@ Sieve will also allow consumers of your API to specify sort order. You can do th
  * `sort=age:asc`
  * `sort=id:desc`
 
+By default, MySQL will sort `null` values first for ascending sorts and last for descending sorts. Depending on the context
+of the column this may not be the desired functionality. You can change this using the following URL queries:
+
+* `sort=priority:asc_nulls_last`
+* `sort=priority:desc_nulls_first`
+
+
 You can set a default sort using the `setDefaultSort` on the`Sieve` class.
 
 ```php

src/Sieve.php

@@ -12,6 +12,8 @@ class Sieve
 
     protected $defaultSort = null;
 
+    protected $sortable = [];
+
     public function __construct(Request $request)
     {
         $this->request = $request;
@@ -37,7 +39,7 @@ public function getFilters()
     public function apply($queryBuilder)
     {
         foreach ($this->getFilters() as $sieveFilter) {
-            /** @var Filter */
+            /** @var ModifiesQueries */
             $filter = $sieveFilter['filter'];
             $property = $sieveFilter['property'];
 
@@ -77,6 +79,16 @@ public function apply($queryBuilder)
             if ($this->getSort() == "$property:asc") {
                 $queryBuilder->orderBy($column, "asc");
             }
+
+            if ($this->getSort() == "$property:asc_nulls_last") {
+                $queryBuilder->orderByRaw("ISNULL(\"$column\") asc")
+                    ->orderBy($column, 'asc');
+            }
+
+            if ($this->getSort() == "$property:desc_nulls_first") {
+                $queryBuilder->orderByRaw("ISNULL(\"$column\") desc")
+                    ->orderBy($column, 'desc');
+            }
         }
 
         return $this;

tests/SieveTest.php

@@ -74,6 +74,54 @@ public function applies_sieve_sorts_to_a_query_builder_asc()
         );
     }
 
+    /**
+     * @test
+     */
+    public function applies_sieve_sorts_to_a_query_builder_asc_nulls_last()
+    {
+        $request = Request::create('/', 'GET', [
+            'sort' => 'name:asc_nulls_last',
+        ]);
+
+        $seive = new Sieve($request);
+        $seive->addFilter('name', new StringFilter);
+
+        /** @var Builder */
+        $builder = $this->app->make(Builder::class);
+        $builder->from('pets');
+
+        $seive->apply($builder);
+
+        $this->assertEquals(
+            'select * from "pets" order by ISNULL("name") asc, "name" asc',
+            $builder->toSql()
+        );
+    }
+
+    /**
+     * @test
+     */
+    public function applies_sieve_sorts_to_a_query_builder_desc_nulls_first()
+    {
+        $request = Request::create('/', 'GET', [
+            'sort' => 'name:desc_nulls_first',
+        ]);
+
+        $seive = new Sieve($request);
+        $seive->addFilter('name', new StringFilter);
+
+        /** @var Builder */
+        $builder = $this->app->make(Builder::class);
+        $builder->from('pets');
+
+        $seive->apply($builder);
+
+        $this->assertEquals(
+            'select * from "pets" order by ISNULL("name") desc, "name" desc',
+            $builder->toSql()
+        );
+    }
+
     /**
      * @test
      */