Added QueryDefaultsPlugin (#67)

* Added QueryDefaultsPlugin

This will fix #66

* Added change log

* Style CI fix

* Added docs about params not beeing encoded

* Updated changelog

* Updated Spec

* Do not use ::class constant

* Updated docs

Author: Nyholm

CHANGELOG.md

@@ -1,5 +1,10 @@
 # Change Log
 
+## Unreleased
+
+### Added
+
+- `QueryDefaultsPlugin` to add default query parameters. 
 
 ## 1.4.2 - 2017-03-18
 

spec/Plugin/QueryDefaultsPluginSpec.php

@@ -0,0 +1,42 @@
+<?php
+
+namespace spec\Http\Client\Common\Plugin;
+
+use Http\Client\Common\Plugin;
+use Psr\Http\Message\RequestInterface;
+use PhpSpec\ObjectBehavior;
+use Psr\Http\Message\UriInterface;
+
+class QueryDefaultsPluginSpec extends ObjectBehavior
+{
+    public function let()
+    {
+        $this->beConstructedWith([]);
+    }
+
+    public function it_is_initializable()
+    {
+        $this->shouldHaveType('Http\Client\Common\Plugin\QueryDefaultsPlugin');
+    }
+
+    public function it_is_a_plugin()
+    {
+        $this->shouldImplement('Http\Client\Common\Plugin');
+    }
+
+    public function it_sets_the_default_header(RequestInterface $request, UriInterface $uri)
+    {
+        $this->beConstructedWith([
+            'foo' => 'bar',
+        ]);
+
+        $request->getUri()->shouldBeCalled()->willReturn($uri);
+        $uri->getQuery()->shouldBeCalled()->willReturn('test=true');
+        $uri->withQuery('test=true&foo=bar')->shouldBeCalled()->willReturn($uri);
+        $request->withUri($uri)->shouldBeCalled()->willReturn($request);
+
+        $this->handleRequest($request, function () {
+        }, function () {
+        });
+    }
+}

src/Plugin/HeaderAppendPlugin.php

@@ -12,7 +12,7 @@
  *
  * This only makes sense for headers that can have multiple values like 'Forwarded'
  *
- * @link https://en.wikipedia.org/wiki/List_of_HTTP_header_fields
+ * @see https://en.wikipedia.org/wiki/List_of_HTTP_header_fields
  *
  * @author Soufiane Ghzal <sghzal@gmail.com>
  */

src/Plugin/QueryDefaultsPlugin.php

@@ -0,0 +1,54 @@
+<?php
+
+namespace Http\Client\Common\Plugin;
+
+use Http\Client\Common\Plugin;
+use Psr\Http\Message\RequestInterface;
+
+/**
+ * Set query to default value if it does not exist.
+ *
+ * If a given query parameter already exists the value wont be replaced and the request wont be changed.
+ *
+ * @author Tobias Nyholm <tobias.nyholm@gmail.com>
+ */
+final class QueryDefaultsPlugin implements Plugin
+{
+    /**
+     * @var array
+     */
+    private $queryParams = [];
+
+    /**
+     * @param array $queryParams Hashmap of query name to query value. Names and values must not be url encoded as
+     *                           this plugin will encode them
+     */
+    public function __construct(array $queryParams)
+    {
+        $this->queryParams = $queryParams;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function handleRequest(RequestInterface $request, callable $next, callable $first)
+    {
+        foreach ($this->queryParams as $name => $value) {
+            $uri = $request->getUri();
+            $array = [];
+            parse_str($uri->getQuery(), $array);
+
+            // If query value is not found
+            if (!isset($array[$name])) {
+                $array[$name] = $value;
+
+                // Create a new request with the new URI with the added query param
+                $request = $request->withUri(
+                    $uri->withQuery(http_build_query($array))
+                );
+            }
+        }
+
+        return $next($request);
+    }
+}