PHPORM-286 Add Query::countByGroup() and other aggregateByGroup() functions

.github/workflows/build-ci.yml

@@ -11,6 +11,8 @@ jobs:
         name: "PHP ${{ matrix.php }} Laravel ${{ matrix.laravel }} MongoDB ${{ matrix.mongodb }} ${{ matrix.mode }}"
 
         strategy:
+            # Tests with Atlas fail randomly
+            fail-fast: false
             matrix:
                 os:
                     - "ubuntu-latest"

src/Query/Builder.php

@@ -30,6 +30,7 @@
 use Override;
 use RuntimeException;
 use stdClass;
+use TypeError;
 
 use function array_fill_keys;
 use function array_filter;
@@ -314,6 +315,7 @@ public function toMql(): array
         if ($this->groups || $this->aggregate) {
             $group   = [];
             $unwinds = [];
+            $set = [];
 
             // Add grouping columns to the $group part of the aggregation pipeline.
             if ($this->groups) {
@@ -324,8 +326,10 @@ public function toMql(): array
                     // this mimics SQL's behaviour a bit.
                     $group[$column] = ['$last' => '$' . $column];
                 }
+            }
 
-                // Do the same for other columns that are selected.
+            // Add the last value of each column when there is no aggregate function.
+            if ($this->groups && ! $this->aggregate) {
                 foreach ($columns as $column) {
                     $key = str_replace('.', '_', $column);
 
@@ -349,15 +353,22 @@ public function toMql(): array
 
                     $aggregations = blank($this->aggregate['columns']) ? [] : $this->aggregate['columns'];
 
-                    if (in_array('*', $aggregations) && $function === 'count') {
+                    if ($column === '*' && $function === 'count' && ! $this->groups) {
                         $options = $this->inheritConnectionOptions($this->options);
 
                         return ['countDocuments' => [$wheres, $options]];
                     }
 
+                    // "aggregate" is the name of the field that will hold the aggregated value.
                     if ($function === 'count') {
-                        // Translate count into sum.
-                        $group['aggregate'] = ['$sum' => 1];
+                        if ($column === '*' || $aggregations === []) {
+                            // Translate count into sum.
+                            $group['aggregate'] = ['$sum' => 1];
+                        } else {
+                            // Count the number of distinct values.
+                            $group['aggregate'] = ['$addToSet' => '$' . $column];
+                            $set['aggregate'] = ['$size' => '$aggregate'];
+                        }
                     } else {
                         $group['aggregate'] = ['$' . $function => '$' . $column];
                     }
@@ -384,6 +395,10 @@ public function toMql(): array
                 $pipeline[] = ['$group' => $group];
             }
 
+            if ($set) {
+                $pipeline[] = ['$set' => $set];
+            }
+
             // Apply order and limit
             if ($this->orders) {
                 $pipeline[] = ['$sort' => $this->aliasIdForQuery($this->orders)];
@@ -559,6 +574,8 @@ public function generateCacheKey()
     /** @return ($function is null ? AggregationBuilder : mixed) */
     public function aggregate($function = null, $columns = ['*'])
     {
+        assert(is_array($columns), new TypeError(sprintf('Argument #2 ($columns) must be of type array, %s given', get_debug_type($columns))));
+
         if ($function === null) {
             if (! trait_exists(FluentFactoryTrait::class)) {
                 // This error will be unreachable when the mongodb/builder package will be merged into mongodb/mongodb
@@ -599,13 +616,36 @@ public function aggregate($function = null, $columns = ['*'])
         $this->columns            = $previousColumns;
         $this->bindings['select'] = $previousSelectBindings;
 
+        // When the aggregation is per group, we return the results as is.
+        if ($this->groups) {
+            return $results->map(function (object $result) {
+                unset($result->id);
+
+                return $result;
+            });
+        }
+
         if (isset($results[0])) {
             $result = (array) $results[0];
 
             return $result['aggregate'];
         }
     }
 
+    /**
+     * {@inheritDoc}
+     *
+     * @see \Illuminate\Database\Query\Builder::aggregateByGroup()
+     */
+    public function aggregateByGroup(string $function, array $columns = ['*'])
+    {
+        if (count($columns) > 1) {
+            throw new InvalidArgumentException('Aggregating by group requires zero or one columns.');
+        }
+
+        return $this->aggregate($function, $columns);
+    }
+
     /** @inheritdoc */
     public function exists()
     {

tests/QueryBuilderTest.php

@@ -7,6 +7,7 @@
 use Carbon\Carbon;
 use DateTime;
 use DateTimeImmutable;
+use Illuminate\Support\Collection as LaravelCollection;
 use Illuminate\Support\Facades\Date;
 use Illuminate\Support\Facades\DB;
 use Illuminate\Support\LazyCollection;
@@ -32,6 +33,7 @@
 use function count;
 use function key;
 use function md5;
+use function method_exists;
 use function sort;
 use function strlen;
 
@@ -617,6 +619,59 @@ public function testSubdocumentArrayAggregate()
         $this->assertEquals(12, DB::table('items')->avg('amount.*.hidden'));
     }
 
+    public function testAggregateGroupBy()
+    {
+        DB::table('users')->insert([
+            ['name' => 'John Doe', 'role' => 'admin', 'score' => 1, 'active' => true],
+            ['name' => 'Jane Doe', 'role' => 'admin', 'score' => 2, 'active' => true],
+            ['name' => 'Robert Roe', 'role' => 'user', 'score' => 4],
+        ]);
+
+        $results = DB::table('users')->groupBy('role')->orderBy('role')->aggregateByGroup('count');
+        $this->assertInstanceOf(LaravelCollection::class, $results);
+        $this->assertEquals([(object) ['role' => 'admin', 'aggregate' => 2], (object) ['role' => 'user', 'aggregate' => 1]], $results->toArray());
+
+        $results = DB::table('users')->groupBy('role')->orderBy('role')->aggregateByGroup('count', ['active']);
+        $this->assertInstanceOf(LaravelCollection::class, $results);
+        $this->assertEquals([(object) ['role' => 'admin', 'aggregate' => 1], (object) ['role' => 'user', 'aggregate' => 0]], $results->toArray());
+
+        $results = DB::table('users')->groupBy('role')->orderBy('role')->aggregateByGroup('max', ['score']);
+        $this->assertInstanceOf(LaravelCollection::class, $results);
+        $this->assertEquals([(object) ['role' => 'admin', 'aggregate' => 2], (object) ['role' => 'user', 'aggregate' => 4]], $results->toArray());
+
+        if (! method_exists(Builder::class, 'countByGroup')) {
+            $this->markTestSkipped('*byGroup functions require Laravel v11.38+');
+        }
+
+        $results = DB::table('users')->groupBy('role')->orderBy('role')->countByGroup();
+        $this->assertInstanceOf(LaravelCollection::class, $results);
+        $this->assertEquals([(object) ['role' => 'admin', 'aggregate' => 2], (object) ['role' => 'user', 'aggregate' => 1]], $results->toArray());
+
+        $results = DB::table('users')->groupBy('role')->orderBy('role')->maxByGroup('score');
+        $this->assertInstanceOf(LaravelCollection::class, $results);
+        $this->assertEquals([(object) ['role' => 'admin', 'aggregate' => 2], (object) ['role' => 'user', 'aggregate' => 4]], $results->toArray());
+
+        $results = DB::table('users')->groupBy('role')->orderBy('role')->minByGroup('score');
+        $this->assertInstanceOf(LaravelCollection::class, $results);
+        $this->assertEquals([(object) ['role' => 'admin', 'aggregate' => 1], (object) ['role' => 'user', 'aggregate' => 4]], $results->toArray());
+
+        $results = DB::table('users')->groupBy('role')->orderBy('role')->sumByGroup('score');
+        $this->assertInstanceOf(LaravelCollection::class, $results);
+        $this->assertEquals([(object) ['role' => 'admin', 'aggregate' => 3], (object) ['role' => 'user', 'aggregate' => 4]], $results->toArray());
+
+        $results = DB::table('users')->groupBy('role')->orderBy('role')->avgByGroup('score');
+        $this->assertInstanceOf(LaravelCollection::class, $results);
+        $this->assertEquals([(object) ['role' => 'admin', 'aggregate' => 1.5], (object) ['role' => 'user', 'aggregate' => 4]], $results->toArray());
+    }
+
+    public function testAggregateByGroupException(): void
+    {
+        $this->expectException(InvalidArgumentException::class);
+        $this->expectExceptionMessage('Aggregating by group requires zero or one columns.');
+
+        DB::table('users')->aggregateByGroup('max', ['foo', 'bar']);
+    }
+
     public function testUpdateWithUpsert()
     {
         DB::table('items')->where('name', 'knife')