Added the guzzle middleware to generate a signature

Author: Justin Hayes

src/Middlewares/Guzzle/GenerateSignature.php

@@ -0,0 +1,43 @@
+<?php
+
+namespace SoapBox\SignedRequests\Middlewares\Guzzle;
+
+use Psr\Http\Message\RequestInterface;
+use SoapBox\SignedRequests\Requests\Generator;
+
+class GenerateSignature
+{
+    /**
+     * An instance of the signed request generator
+     *
+     * @var \SoapBox\SignedRequests\Requests\Generator
+     */
+    protected $generator;
+
+    /**
+     * Expect an instance of the generator so we can sign the request
+     *
+     * @param \SoapBox\SignedRequests\Requests\Generator $generator
+     *        An instance of the signed request generator
+     */
+    public function __construct(Generator $generator)
+    {
+        $this->generator = $generator;
+    }
+
+    /**
+     * Return the middleware callable. This callable function signs the request.
+     *
+     * @param callable $handler
+     *        The next handler to invoke
+     *
+     * @return callable
+     */
+    public function __invoke(callable $handler) : callable
+    {
+        return function (RequestInterface $request, array $options) use ($handler) {
+            $request = $this->generator->sign($request);
+            return $handler($request, $options);
+        };
+    }
+}

tests/Middlewares/Guzzle/GenerateSignatureTest.php

@@ -0,0 +1,63 @@
+<?php
+
+namespace Tests\Midlewares\Guzzle;
+
+use Mockery;
+use Tests\TestCase;
+use GuzzleHttp\Psr7\Request;
+use Illuminate\Config\Repository;
+use Psr\Http\Message\RequestInterface;
+use SoapBox\SignedRequests\Requests\Generator;
+use SoapBox\SignedRequests\Middlewares\Guzzle\GenerateSignature;
+
+class GenerateSignatureTest extends TestCase
+{
+    /**
+     * @test
+     */
+    public function it_can_be_constructed()
+    {
+        $middleware = new GenerateSignature(new Generator(Mockery::mock(Repository::class)));
+        $this->assertInstanceOf(GenerateSignature::class, $middleware);
+    }
+
+    /**
+     * @test
+     */
+    public function it_signs_the_request()
+    {
+        $configurations = Mockery::mock(Repository::class);
+        $configurations->shouldReceive('get')
+            ->with('signed-requests.cache-prefix')
+            ->andReturn('prefix');
+        $configurations->shouldReceive('get')
+            ->with('signed-requests.request-replay.tolerance')
+            ->andReturn(60);
+        $configurations->shouldReceive('get')
+            ->with('signed-requests.headers.algorithm')
+            ->andReturn('Test-Algorithm');
+        $configurations->shouldReceive('get')
+            ->with('signed-requests.headers.signature')
+            ->andReturn('Test-Signature');
+        $algorithm = $configurations->shouldReceive('get')
+            ->with('signed-requests.algorithm')
+            ->andReturn('sha256');
+        $key = $configurations->shouldReceive('get')
+            ->with('signed-requests.key')
+            ->andReturn('bigsecretrighthereitellyouwhat');
+        $middleware = new GenerateSignature(new Generator($configurations));
+
+        $nextHandler = function (RequestInterface $request, array $options) {
+            return $request;
+        };
+
+        $request = new Request('get', 'tested');
+
+        $handler = call_user_func_array($middleware, [$nextHandler]);
+        $request = $handler($request, []);
+
+        $this->assertTrue($request->hasHeader('Test-Signature'));
+        $this->assertTrue($request->hasHeader('Test-Algorithm'));
+        $this->assertSame('sha256', $request->getHeader('Test-Algorithm')[0]);
+    }
+}