Custom header support

Resolves #12

Author: brandonkelly

CHANGELOG.md

@@ -1,5 +1,10 @@
 # Release Notes for Webhooks for Craft CMS
 
+## Unreleased
+
+### Added
+- Webhooks can now specify custom request headers. ([#12](https://github.com/craftcms/webhooks/issues/12))
+
 ## 2.1.0 - 2019-07-26
 
 ### Added

README.md

@@ -132,6 +132,18 @@ class ArticleFilter implements FilterInterface
 }
 ```
 
+#### Sending Custom Headers
+
+You can send custom headers along with webhook requests using the Custom Headers setting.
+
+<img src="./images/custom-headers.png" width="696" height="292" alt="Screenshot of the Custom Headers setting">
+
+Header values can be set to an environment variable using the `$VARIABLE_NAME` syntax, or a Twig template.
+
+An `event` variable will be available to the Twig template, set to the event that triggered the webhook.
+
+You can have multiple headers that have the same name, and if a header value takes up multiple lines (after any empty lines have been discarded), each line will be sent as its own header, all using the same header name.
+
 #### Sending More Data
 
 If you need more data than what’s in the default POST request payload, you can fill in the “Extra User Attributes”, “Extra Sender Attributes”, and “Extra Event Attributes” fields.

images/custom-headers.png

@@ -79,7 +79,7 @@ class Plugin extends \craft\base\Plugin
     /**
      * @inheritdoc
      */
-    public $schemaVersion = '2.1.0';
+    public $schemaVersion = '2.2.0';
 
     // Public Methods
     // =========================================================================
@@ -118,10 +118,12 @@ public function init()
                     }
                 }
 
+                $view = Craft::$app->getView();
+
                 if ($webhook->method === 'post') {
                     // Build out the body data
                     if ($webhook->payloadTemplate) {
-                        $json = Craft::$app->getView()->renderString($webhook->payloadTemplate, [
+                        $json = $view->renderString($webhook->payloadTemplate, [
                             'event' => $e,
                         ]);
                         $data = Json::decodeIfJson($json);
@@ -147,15 +149,39 @@ public function init()
                     }
                 }
 
-                // Queue the send request up
+                // Set the headers and body
                 $headers = [];
+
+                foreach ($webhook->headers as $header) {
+                    $header['value'] = Craft::parseEnv($header['value']);
+                    if (strpos($header['value'], '{') !== false) {
+                        $header['value'] = $view->renderString($header['value'], [
+                            'event' => $e,
+                        ]);
+                    }
+                    // Get the trimmed lines
+                    $lines = array_filter(array_map('trim', preg_split('/[\r\n]+/', $header['value'])));
+                    // Add to the header array one-by-one, ensuring that we don't overwrite existing values
+                    foreach ($lines as $line) {
+                        if (!isset($headers[$header['name']])) {
+                            $headers[$header['name']] = $line;
+                        } else {
+                            if (!is_array($headers[$header['name']])) {
+                                $headers[$header['name']] = [$headers[$header['name']]];
+                            }
+                            $headers[$header['name']][] = $line;
+                        }
+                    }
+                }
+
                 if (isset($data) && is_array($data)) {
                     $body = Json::encode($data);
                     $headers['Content-Type'] = 'application/json';
                 } else {
                     $body = $data ?? null;
                 }
 
+                // Queue the send request up
                 $this->request($webhook->method, $webhook->url, $headers, $body, $webhook->id);
             });
         }

src/Plugin.php

@@ -62,6 +62,11 @@ class Webhook extends Model
      */
     public $url;
 
+    /**
+     * @var array
+     */
+    public $headers = [];
+
     /**
      * @var string|null
      */
@@ -162,6 +167,12 @@ function() {
                     }
                 }
             ],
+            [
+                ['headers'],
+                function() {
+                    $this->headers = $this->headers ? array_values($this->headers) : [];
+                }
+            ],
             [['userAttributes', 'senderAttributes'], 'validateAttributeList'],
             [['eventAttributes'], 'validateAttributeList', 'params' => ['regex' => '/^[a-z]\w*\.[a-z]\w*(?:\.[a-z]\w*)*$/i']],
             [['payloadTemplate'], 'validatePayloadTemplate'],

src/Webhook.php

@@ -200,6 +200,7 @@ public function saveWebhook(Webhook $webhook, bool $runValidation = true): bool
             'filters' => $webhook->filters ? Json::encode($webhook->filters) : null,
             'method' => $webhook->method,
             'url' => $webhook->url,
+            'headers' => $webhook->headers ? Json::encode($webhook->headers) : null,
             'userAttributes' => $webhook->userAttributes,
             'senderAttributes' => $webhook->senderAttributes,
             'eventAttributes' => $webhook->eventAttributes,
@@ -248,6 +249,7 @@ private function _createWebhookQuery(): Query
                 'filters',
                 'method',
                 'url',
+                'headers',
                 'userAttributes',
                 'senderAttributes',
                 'eventAttributes',
@@ -273,6 +275,12 @@ private function _createWebhook(array $result, bool $isMysql = null): Webhook
             $result['filters'] = [];
         }
 
+        if ($result['headers']) {
+            $result['headers'] = Json::decode($result['headers']);
+        } else {
+            $result['headers'] = [];
+        }
+
         return new Webhook($result);
     }
 

src/WebhookManager.php

@@ -36,6 +36,7 @@ public function safeUp()
             'filters' => $this->text(),
             'method' => $this->string(10)->notNull(),
             'url' => $this->string()->notNull(),
+            'headers' => $this->text(),
             'userAttributes' => $this->text(),
             'senderAttributes' => $this->text(),
             'eventAttributes' => $this->text(),

src/migrations/Install.php

@@ -0,0 +1,29 @@
+<?php
+
+namespace craft\webhooks\migrations;
+
+use Craft;
+use craft\db\Migration;
+
+/**
+ * m190724_202705_custom_headers migration.
+ */
+class m190724_202705_custom_headers extends Migration
+{
+    /**
+     * @inheritdoc
+     */
+    public function safeUp()
+    {
+        $this->addColumn('{{%webhooks}}', 'headers', $this->text()->after('url'));
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function safeDown()
+    {
+        echo "m190724_202705_custom_headers cannot be reverted.\n";
+        return false;
+    }
+}

src/migrations/m190724_202705_custom_headers.php

@@ -14,6 +14,7 @@
  * @property string|null $filters
  * @property string $event
  * @property string $url
+ * @property string|null $headers
  * @property string|null $userAttributes
  * @property string|null $senderAttributes
  * @property string|null $eventAttributes

src/records/Webhook.php

@@ -131,6 +131,30 @@
         errors: webhook.getErrors('url')
     }, urlInput) }}
 
+    {{ forms.editableTableField({
+        id: 'headers',
+        name: 'headers',
+        label: 'Custom Headers'|t('webhooks'),
+        instructions: 'Any custom headers that should be sent.'|t('webhooks'),
+        cols: {
+            name: {
+                heading: 'Name'|t('webhooks'),
+                type: 'singleline',
+                code: true,
+                placeholder: 'X-Foo-Bar',
+            },
+            value: {
+                heading: 'Value'|t('webhooks'),
+                info: 'Can be set to an environment variable (`$VARIABLE_NAME`) or Twig code.'|t('webhooks'),
+                type: 'multiline',
+                code: true,
+                placeholder: '{{ event.sender.fooBar }}',
+            }
+        },
+        rows: webhook.headers,
+        addRowLabel: 'Add a header'|t('webhooks'),
+    }) }}
+
     <div id="method-settings--post" {% if webhook.method == 'get' %}class="hidden"{% endif %}>
 
         <hr>