Initial SchemaType implementations

Author: tPl0ch

src/Constants.php

@@ -18,6 +18,9 @@ final class Constants
     public const ACCEPT_HEADER = [self::ACCEPT => 'application/vnd.schemaregistry.v1+json'];
     public const CONTENT_TYPE_HEADER = [self::CONTENT_TYPE => 'application/vnd.schemaregistry.v1+json'];
     public const CONTENT_TYPE = 'Content-Type';
+    public const AVRO_TYPE = 'AVRO';
+    public const JSON_TYPE = 'JSON';
+    public const PROTOBUF_TYPE = 'PROTOBUF';
 
     private function __construct()
     {

src/Schemas/AvroSchemaType.php

@@ -0,0 +1,39 @@
+<?php
+
+declare(strict_types=1);
+
+namespace FlixTech\SchemaRegistryApi\Schemas;
+
+use FlixTech\SchemaRegistryApi\Constants;
+
+/**
+ * @implements SchemaType<AvroSchemaType>
+ */
+final class AvroSchemaType extends ValueObject implements SchemaType
+{
+    /**
+     * @var AvroSchemaType
+     */
+    private static $instance;
+
+    public static function instance(): AvroSchemaType
+    {
+        if (self::$instance !== null) {
+            return self::$instance;
+        }
+
+        self::$instance = new self();
+
+        return self::$instance;
+    }
+
+    public function value(): string
+    {
+        return Constants::AVRO_TYPE;
+    }
+
+    public function __toString(): string
+    {
+        return $this->value();
+    }
+}

src/Schemas/JsonSchemaType.php

@@ -0,0 +1,39 @@
+<?php
+
+declare(strict_types=1);
+
+namespace FlixTech\SchemaRegistryApi\Schemas;
+
+use FlixTech\SchemaRegistryApi\Constants;
+
+/**
+ * @implements SchemaType<JsonSchemaType>
+ */
+final class JsonSchemaType extends ValueObject implements SchemaType
+{
+    /**
+     * @var JsonSchemaType
+     */
+    private static $instance;
+
+    public static function instance(): JsonSchemaType
+    {
+        if (self::$instance !== null) {
+            return self::$instance;
+        }
+
+        self::$instance = new self();
+
+        return self::$instance;
+    }
+
+    public function value(): string
+    {
+        return Constants::JSON_TYPE;
+    }
+
+    public function __toString(): string
+    {
+        return $this->value();
+    }
+}

src/Schemas/ProtobufSchemaType.php

@@ -0,0 +1,39 @@
+<?php
+
+declare(strict_types=1);
+
+namespace FlixTech\SchemaRegistryApi\Schemas;
+
+use FlixTech\SchemaRegistryApi\Constants;
+
+/**
+ * @implements SchemaType<ProtobufSchemaType>
+ */
+final class ProtobufSchemaType extends ValueObject implements SchemaType
+{
+    /**
+     * @var ProtobufSchemaType
+     */
+    private static $instance;
+
+    public static function instance(): ProtobufSchemaType
+    {
+        if (self::$instance !== null) {
+            return self::$instance;
+        }
+
+        self::$instance = new self();
+
+        return self::$instance;
+    }
+
+    public function value(): string
+    {
+        return Constants::PROTOBUF_TYPE;
+    }
+
+    public function __toString(): string
+    {
+        return $this->value();
+    }
+}

src/Schemas/SchemaType.php

@@ -0,0 +1,18 @@
+<?php
+
+declare(strict_types=1);
+
+namespace FlixTech\SchemaRegistryApi\Schemas;
+
+/**
+ * @phpstan-template T
+ */
+interface SchemaType
+{
+    /**
+     * @phpstan-return T
+     */
+    public static function instance();
+
+    public function value(): string;
+}

src/Schemas/ValueObject.php

@@ -0,0 +1,19 @@
+<?php
+
+declare(strict_types=1);
+
+namespace FlixTech\SchemaRegistryApi\Schemas;
+
+abstract class ValueObject
+{
+    final protected function __construct()
+    {
+    }
+
+    /**
+     * @codeCoverageIgnore
+     */
+    final private function __clone()
+    {
+    }
+}

test/Schemas/SchemaTypeTest.php

@@ -0,0 +1,63 @@
+<?php
+
+declare(strict_types=1);
+
+namespace FlixTech\SchemaRegistryApi\Test\Schemas;
+
+use Error;
+use FlixTech\SchemaRegistryApi\Constants;
+use FlixTech\SchemaRegistryApi\Schemas\AvroSchemaType;
+use FlixTech\SchemaRegistryApi\Schemas\JsonSchemaType;
+use FlixTech\SchemaRegistryApi\Schemas\ProtobufSchemaType;
+use Generator;
+use PHPUnit\Framework\TestCase;
+
+class SchemaTypeTest extends TestCase
+{
+    /**
+     * @test
+     * @dataProvider provideSchemaTypes
+     *
+     * @phpstan-template template T of SchemaType
+     * @param string $className
+     * @phpstan-param class-string<T> $className
+     * @param string $expected
+     */
+    public function type_should_match_the_value(string $className, string $expected): void
+    {
+        self::assertEquals($expected, $className::instance()->value());
+        self::assertEquals($expected, (string)$className::instance());
+    }
+
+    /**
+     * @test
+     * @dataProvider provideSchemaTypes
+     *
+     * @phpstan-template template T of SchemaType
+     * @param string $className
+     * @phpstan-param class-string<T> $className
+     */
+    public function types_cannot_be_cloned(string $className): void
+    {
+        $this->expectException(Error::class);
+        $result = clone $className::instance();
+    }
+
+    public function provideSchemaTypes(): Generator
+    {
+        yield 'AvroSchemaType' => [
+            AvroSchemaType::class,
+            Constants::AVRO_TYPE,
+        ];
+
+        yield 'JsonSchemaType' => [
+            JsonSchemaType::class,
+            Constants::JSON_TYPE,
+        ];
+
+        yield 'ProtobufSchemaType' => [
+            ProtobufSchemaType::class,
+            Constants::PROTOBUF_TYPE,
+        ];
+    }
+}