Merge 67a5bc0 into 4298834

README.md

@@ -29,6 +29,7 @@ composer require umbrellio/laravel-pg-extensions
  - [Working with CHECK constraints](#check-constraints-creation)
  - [Working with partitions](#partitions)
  - [Check existing index before manipulation](#check-existing-index)
+ - [Getting foreign keys for table](#get-foreign-keys)
 
 ### Extended table creation
 
@@ -74,6 +75,21 @@ Schema::create('users', function (Blueprint $table) {
 });
 ```
 
+### Get foreign keys
+
+Example:
+```php
+// Facade methods:
+/** @var ForeignKeyDefinition[] $fks */
+$fks = Schema::getForeignKeys('some_table');
+
+foreach ($fks as $fk) {
+    // $fk->source_column_name
+    // $fk->target_table_name
+    // $fk->target_column_name
+}
+```
+
 ### Extended unique indexes creation
 
 Example:

src/.meta.php

@@ -1,5 +1,16 @@
 <?php
 
+namespace Illuminate\Support\Facades {
+    use Umbrellio\Postgres\Schema\Definitions\ForeignKeyDefinition;
+
+    /**
+     * @method ForeignKeyDefinition[] getForeignKeys(string $tableName)
+     */
+    class Schema {
+
+    }
+}
+
 namespace Illuminate\Database\Schema {
 
     use Closure;

src/Schema/Builder.php

@@ -36,6 +36,13 @@ public function hasView(string $view): bool
         ])) > 0;
     }
 
+    public function getForeignKeys(string $tableName): array
+    {
+        return $this->connection->selectFromWriteConnection(
+            $this->grammar->compileForeignKeysListing($tableName)
+        );
+    }
+
     public function getViewDefinition($view): string
     {
         $results = $this->connection->selectFromWriteConnection($this->grammar->compileViewDefinition(), [

src/Schema/Definitions/ForeignKeyDefinition.php

@@ -0,0 +1,13 @@
+<?php declare(strict_types=1);
+
+
+namespace Umbrellio\Postgres\Schema\Definitions;
+
+/**
+ * @property string $source_column_name
+ * @property string $target_table_name
+ * @property string $target_column_name
+ */
+class ForeignKeyDefinition
+{
+}

src/Schema/Grammars/PostgresGrammar.php

@@ -70,6 +70,25 @@ public function compileViewExists(): string
         return 'select * from information_schema.views where table_schema = ? and table_name = ?';
     }
 
+    public function compileForeignKeysListing(string $tableName): string
+    {
+        return sprintf("
+            SELECT
+                kcu.column_name as source_column_name,
+                ccu.table_name AS target_table_name,
+                ccu.column_name AS target_column_name
+            FROM
+                information_schema.table_constraints AS tc
+                    JOIN information_schema.key_column_usage AS kcu
+                         ON tc.constraint_name = kcu.constraint_name
+                             AND tc.table_schema = kcu.table_schema
+                    JOIN information_schema.constraint_column_usage AS ccu
+                         ON ccu.constraint_name = tc.constraint_name
+                             AND ccu.table_schema = tc.table_schema
+            WHERE tc.constraint_type = 'FOREIGN KEY' AND tc.table_name='%s';
+        ", $tableName);
+    }
+
     public function compileViewDefinition(): string
     {
         return 'select view_definition from information_schema.views where table_schema = ? and table_name = ?';

tests/Functional/Schema/GetForeignKeysTest.php

@@ -0,0 +1,75 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Umbrellio\Postgres\Tests\Functional;
+
+use Illuminate\Foundation\Testing\DatabaseTransactions;
+use Illuminate\Support\Facades\Schema;
+use Umbrellio\Postgres\Helpers\ViewAssertions;
+use Umbrellio\Postgres\Schema\Blueprint;
+use Umbrellio\Postgres\Tests\FunctionalTestCase;
+
+class GetForeignKeysTest extends FunctionalTestCase
+{
+    use DatabaseTransactions;
+
+    protected function setUp(): void
+    {
+        parent::setUp();
+
+        Schema::create('test_foreign_table1', function (Blueprint $table) {
+            $table->increments('id');
+            $table->string('name');
+        });
+
+        Schema::create('test_foreign_table2', function (Blueprint $table) {
+            $table->increments('id');
+            $table->string('name');
+        });
+
+        Schema::create('test_table', function (Blueprint $table) {
+            $table->increments('id');
+            $table->string('name');
+            $table->bigInteger('test1_id');
+            $table->bigInteger('test2_id');
+            $table->foreign(['test1_id'])->references('id')->on('test_foreign_table1');
+            $table->foreign(['test2_id'])->references('id')->on('test_foreign_table2');
+        });
+    }
+
+    protected function tearDown(): void
+    {
+        Schema::dropIfExists('test_table');
+        Schema::dropIfExists('test_foreign_table1');
+        Schema::dropIfExists('test_foreign_table2');
+
+        parent::tearDown();
+    }
+
+    /**
+     * @test
+     */
+    public function getForeignKeys(): void
+    {
+        $foreignKeys = Schema::getForeignKeys('test_table');
+
+        $this->assertSame(
+            (array) $foreignKeys[0],
+            [
+                'source_column_name' => 'test1_id',
+                'target_table_name' => 'test_foreign_table1',
+                'target_column_name' => 'id',
+            ]
+        );
+
+        $this->assertSame(
+            (array) $foreignKeys[1],
+            [
+                'source_column_name' => 'test2_id',
+                'target_table_name' => 'test_foreign_table2',
+                'target_column_name' => 'id',
+            ]
+        );
+    }
+}