Merge branch 'L02COLL-270-add-header-methods' into prod

* L02COLL-270-add-header-methods:
  L02COLL-270 set version 0.3.1
  L02COLL-270 add methods for get/set single header

composer.json

@@ -9,7 +9,7 @@
             "homepage": "http://library.wur.nl"
         }
     ],
-    "version": "0.3.0",
+    "version": "0.3.1",
     "require": {
         "php": ">=7.0.0",
         "guzzlehttp/guzzle": "^6.3"

src/Library/HttpClientTrait.php

@@ -80,6 +80,17 @@ trait HttpClientTrait {
         return $this->http_headers;
     }
 
+
+    /**
+     * getter for single http client request header
+     * @param string name name of header
+     * @return string value of header or null if not set
+     */
+    public function get_http_header(string $name) {
+
+        return key_exists($name, $this->http_headers) ? $this->http_headers[$name] : null;
+    }
+
     /**
      * setter for http client request headers
      * @param array $headers http request headers, see GuzzleHttp documentation
@@ -91,6 +102,18 @@ trait HttpClientTrait {
         return $this;
     }
 
+    /**
+     * setter for single http client request header
+     * @param string name name of header
+     * @param string value value for header
+     * @return $this
+     */
+    public function set_http_header(string $name, string $value) {
+
+        $this->http_headers[$name] = $value;
+        return $this;
+    }
+
 
     /**
      * getter for http client options

tests/Library/HttpClientTraitTest.php

@@ -43,8 +43,17 @@ class HttpClientTraitTest extends \PHPUnit_Framework_TestCase {
         $headers = ["Content-Type" => "plain/text"];
         $this->assertEquals($testclient, $testclient->set_http_headers($headers), "set_http_headers() returns this");
         $this->assertEquals($headers, $testclient->get_http_headers(), "get_http_headers() returns set headers");
-    }
 
+        // set/get single header
+        $testclient->set_http_header("Accept", "application/xml");
+        $this->assertEquals("application/xml", $testclient->get_http_header("Accept"), "set_http_header() sets header");
+        $headers["Accept"] = "application/xml";
+        $this->assertEquals($headers, $testclient->get_http_headers(), "get_http_headers() returns all headers");
+
+        $testclient->set_http_header("Content-Type", "text/html");
+        $headers["Content-Type"] = "text/html";
+        $this->assertEquals($headers, $testclient->get_http_headers(), "get_http_headers() returns all headers");
+    }
 
     public function test_get_set_http_options() {