Support middleware on the client level

Author: WyriHaximus

infection.json.dist

@@ -27,6 +27,7 @@
          },
          "IncrementInteger": {
              "ignore": [
+                 "WyriHaximus\\React\\SimpleORM\\Repository::create",
                  "WyriHaximus\\React\\SimpleORM\\Repository::count",
                  "WyriHaximus\\React\\SimpleORM\\Repository::buildTree",
                  "WyriHaximus\\React\\SimpleORM\\Repository::translateFieldName"

phpstan.neon

@@ -2,7 +2,6 @@ parameters:
 	ignoreErrors:
 		- '#Class WyriHaximus\\React\\Tests\\SimpleORM\\Stub\\[a-zA-Z0-9_]+ is neither abstract nor final.#'
 		- '#Cannot call method getDocBlockTypes() on Roave\\BetterReflection\\Reflection\\ReflectionProperty|null.#'
-		- '#Constructor in WyriHaximus\\React\\SimpleORM\\Client has parameter \$annotationReader with default value.#'
 		- '#Argument of an invalid type WyriHaximus\\React\\SimpleORM\\Annotation\\[a-zA-Z0-9_]+ supplied for foreach, only iterables are supported.#'
 		- '#Variable property access on \$this\(WyriHaximus\\React\\SimpleORM\\Annotation\\[a-zA-Z0-9_]+\).#'
 	classesAllowedToBeExtended:

src/Client.php

@@ -8,6 +8,9 @@
 use Plasma\SQL\Grammar\PostgreSQL;
 use Plasma\SQL\QueryBuilder;
 use Rx\Observable;
+use WyriHaximus\React\SimpleORM\Middleware\ExecuteQueryMiddleware;
+use WyriHaximus\React\SimpleORM\Middleware\GrammarMiddleware;
+use function ApiClients\Tools\Rx\unwrapObservableFromPromise;
 
 final class Client implements ClientInterface
 {
@@ -20,10 +23,37 @@ final class Client implements ClientInterface
     /** @var Repository[] */
     private $repositories = [];
 
-    public function __construct(PgClient $client, ?Reader $annotationReader = null)
+    /** @var MiddlewareRunner */
+    private $middlewareRunner;
+
+    /**
+     * @param array<int, MiddlewareInterface> $middleware
+     */
+    public static function create(PgClient $client, MiddlewareInterface ...$middleware): self
+    {
+        return new self($client, new AnnotationReader(), ...$middleware);
+    }
+
+    /**
+     * @param array<int, MiddlewareInterface> $middleware
+     */
+    public static function createWithAnnotationReader(PgClient $client, Reader $annotationReader, MiddlewareInterface ...$middleware): self
+    {
+        return new self($client, $annotationReader, ...$middleware);
+    }
+
+    /**
+     * @param array<int, MiddlewareInterface> $middleware
+     */
+    private function __construct(PgClient $client, Reader $annotationReader, MiddlewareInterface ...$middleware)
     {
         $this->client = $client;
-        $this->entityInspector = new EntityInspector($annotationReader ?? new AnnotationReader());
+        $this->entityInspector = new EntityInspector($annotationReader);
+
+        $middleware[] = new GrammarMiddleware(new PostgreSQL());
+        $middleware[] = new ExecuteQueryMiddleware($this->client);
+
+        $this->middlewareRunner = new MiddlewareRunner(...$middleware);
     }
 
     public function getRepository(string $entity): RepositoryInterface
@@ -37,8 +67,6 @@ public function getRepository(string $entity): RepositoryInterface
 
     public function query(QueryBuilder $query): Observable
     {
-        $query = $query->withGrammar(new PostgreSQL());
-
-        return $this->client->executeStatement($query->getQuery(), $query->getParameters());
+        return unwrapObservableFromPromise($this->middlewareRunner->query($query));
     }
 }

src/Middleware/ExecuteQueryMiddleware.php

@@ -0,0 +1,25 @@
+<?php declare(strict_types=1);
+
+namespace WyriHaximus\React\SimpleORM\Middleware;
+
+use PgAsync\Client as PgClient;
+use Plasma\SQL\QueryBuilder;
+use React\Promise\PromiseInterface;
+use WyriHaximus\React\SimpleORM\MiddlewareInterface;
+use function React\Promise\resolve;
+
+final class ExecuteQueryMiddleware implements MiddlewareInterface
+{
+    /** @var PgClient */
+    private $client;
+
+    public function __construct(PgClient $client)
+    {
+        $this->client = $client;
+    }
+
+    public function query(QueryBuilder $query): PromiseInterface
+    {
+        return resolve($this->client->executeStatement($query->getQuery(), $query->getParameters()));
+    }
+}

src/Middleware/GrammarMiddleware.php

@@ -0,0 +1,25 @@
+<?php declare(strict_types=1);
+
+namespace WyriHaximus\React\SimpleORM\Middleware;
+
+use Plasma\SQL\GrammarInterface;
+use Plasma\SQL\QueryBuilder;
+use React\Promise\PromiseInterface;
+use WyriHaximus\React\SimpleORM\MiddlewareInterface;
+use function React\Promise\resolve;
+
+final class GrammarMiddleware implements MiddlewareInterface
+{
+    /** @var GrammarInterface */
+    private $grammer;
+
+    public function __construct(GrammarInterface $grammer)
+    {
+        $this->grammer = $grammer;
+    }
+
+    public function query(QueryBuilder $query): PromiseInterface
+    {
+        return resolve($query->withGrammar($this->grammer));
+    }
+}

src/Middleware/QueryCountMiddleware.php

@@ -0,0 +1,34 @@
+<?php declare(strict_types=1);
+
+namespace WyriHaximus\React\SimpleORM\Middleware;
+
+use PgAsync\Client as PgClient;
+use Plasma\SQL\QueryBuilder;
+use React\Promise\PromiseInterface;
+use WyriHaximus\React\SimpleORM\MiddlewareInterface;
+use function React\Promise\resolve;
+
+final class QueryCountMiddleware implements MiddlewareInterface
+{
+    private const ZERO = 0;
+
+    /** @var int */
+    private $count = self::ZERO;
+
+    public function query(QueryBuilder $query): PromiseInterface
+    {
+        $this->count++;
+
+        return resolve($query);
+    }
+
+    public function getCount(): int
+    {
+        return $this->count;
+    }
+
+    public function resetCount(): void
+    {
+        $this->count = 0;
+    }
+}

src/MiddlewareInterface.php

@@ -0,0 +1,18 @@
+<?php declare(strict_types=1);
+
+namespace WyriHaximus\React\SimpleORM;
+
+use Plasma\SQL\QueryBuilder;
+use React\Promise\PromiseInterface;
+
+interface MiddlewareInterface
+{
+    /**
+     * Returns the (modified) query through a promise.
+     *
+     * @param QueryBuilder $query
+     *
+     * @return PromiseInterface
+     */
+    public function query(QueryBuilder $query): PromiseInterface;
+}

src/MiddlewareRunner.php

@@ -0,0 +1,38 @@
+<?php declare(strict_types=1);
+
+namespace WyriHaximus\React\SimpleORM;
+
+use Plasma\SQL\QueryBuilder;
+use Psr\Http\Message\ServerRequestInterface;
+use React\Promise\PromiseInterface;
+
+final class MiddlewareRunner
+{
+    /** @var MiddlewareInterface[] */
+    private $middleware;
+
+    /**
+     * @param array<int, MiddlewareInterface> $middleware
+     */
+    public function __construct(MiddlewareInterface ...$middleware)
+    {
+        $this->middleware = $middleware;
+    }
+
+    public function query(QueryBuilder $query): PromiseInterface
+    {
+        return $this->call($query, 0);
+    }
+
+    private function call(QueryBuilder $query, int $position): PromiseInterface
+    {
+        // final request handler will be invoked without hooking into the promise
+        if (!array_key_exists($position + 1, $this->middleware)) {
+            return $this->middleware[$position]->query($query);
+        }
+
+        return $this->middleware[$position]->query($query)->then(function (QueryBuilder $query) use ($position) {
+            return $this->call($query, $position + 1);
+        });
+    }
+}

tests/ClientTest.php

@@ -40,7 +40,7 @@ protected function setUp(): void
 
         $this->pgClient = $this->prophesize(PgClient::class);
         $this->annotationReader = $this->prophesize(Reader::class);
-        $this->client = new Client($this->pgClient->reveal(), $this->annotationReader->reveal());
+        $this->client = Client::createWithAnnotationReader($this->pgClient->reveal(), $this->annotationReader->reveal());
     }
 
     public function testGetRepository(): void