added support for sending data through HTTP headers (fixed #18)

README.md

@@ -36,6 +36,7 @@ examples and [phpdebugbar.com](http://phpdebugbar.com) for a live example.
 Integrations with other frameworks:
 
   - [Laravel](https://github.com/barryvdh/laravel-debugbar) (project by barryvdh)
+  - [Atomik](http://atomikframework.com/docs/error-log-debug.html#debug-bar)
 
 *(drop me a message or submit a PR to add your DebugBar related project here)*
 
@@ -63,7 +64,6 @@ The easiest way is using the `render()` functions
 ```PHP
 <?php
 use DebugBar\StandardDebugBar;
-use DebugBar\JavascriptRenderer;
 
 $debugbar = new StandardDebugBar();
 $debugbarRenderer = $debugbar->getJavascriptRenderer();

demo/ajax.php

@@ -2,9 +2,6 @@
 
 include 'bootstrap.php';
 $debugbar['messages']->addMessage('hello from ajax');
-
-?>
-hello from AJAX
-<?php
-    echo $debugbarRenderer->render(false);
+$debugbar->sendDataInHeaders();
 ?>
+hello from AJAX

docs/ajax.md

@@ -0,0 +1,24 @@
+# AJAX
+
+As mentioned in the previous chapter, if you are performing AJAX requests
+which return HTML content, you can use `JavascriptRenderer::render(false)`.
+
+In the case you are sending back non-HTML data (eg: JSON), the DebugBar can 
+send data to the client using HTTP headers using the `sendDataInHeaders()` method
+(no need to use the `JavascriptRenderer`):
+
+    $debugbar = new DebugBar();
+    // ...
+    $debugbar->sendDataInHeaders();
+
+On the client side, an instance of `PhpDebugBar.AjaxHandler` will
+parse the headers and add the dataset to the debugbar.
+
+The AjaxHandler automatically binds to jQuery's *ajaxComplete* event
+so if you are using jQuery, you have nothing to configure.
+
+If you're not using jQuery, you can call `AjaxHandler.handle(xhr)`.
+If you are using the `JavascriptRenderer` initialization, the instance 
+of `AjaxHandler` is stored in the `ajaxHandler` property of the `DebugBar` object.
+
+    debugbar.ajaxHandler.handle(xhr);

docs/manifest.json

@@ -6,6 +6,7 @@
         "../README.md",
         "data_collectors.md",
         "rendering.md",
+        "ajax.md",
         "base_collectors.md",
         "bridge_collectors.md",
         "storage.md",

src/DebugBar/DebugBar.php

@@ -202,6 +202,34 @@ class DebugBar implements ArrayAccess
         return $this->data;
     }
 
+    /**
+     * Sends the data through the HTTP headers
+     * 
+     * @param string $headerName
+     * @param integer $maxHeaderLength
+     */
+    public function sendDataInHeaders($headerName = 'phpdebugbar', $maxHeaderLength = 4096)
+    {
+        $data = rawurlencode(json_encode(array(
+            'id' => $this->getCurrentRequestId(),
+            'data' => $this->getData()
+        )));
+        $chunks = array();
+
+        while (strlen($data) > $maxHeaderLength) {
+            $chunks[] = substr($data, 0, $maxHeaderLength);
+            $data = substr($data, $maxHeaderLength);
+        }
+        $chunks[] = $data;
+
+        for ($i = 0, $c = count($chunks); $i < $c; $i++) {
+            $name = $headerName . ($i > 0 ? "-$i" : '');
+            header("$name: {$chunks[$i]}");
+        }
+        
+        return $this;
+    }
+
     /**
      * Returns a JavascriptRenderer for this instance
      * 

src/DebugBar/JavascriptRenderer.php

@@ -49,6 +49,10 @@ class JavascriptRenderer
 
     protected $ignoredCollectors = array();
 
+    protected $ajaxHandlerClass = 'PhpDebugBar.AjaxHandler';
+
+    protected $ajaxHandlerBindToJquery = true;
+
     protected $openHandlerClass = 'PhpDebugBar.OpenHandler';
 
     protected $openHandlerUrl;
@@ -354,6 +358,50 @@ class JavascriptRenderer
         ), $type);
     }
 
+    /**
+     * Sets the class name of the ajax handler
+     *
+     * Set to false to disable
+     * 
+     * @param string $className
+     */
+    public function setAjaxHandlerClass($className)
+    {
+        $this->ajaxHandlerClass = $className;
+        return $this;
+    }
+
+    /**
+     * Returns the class name of the ajax handler
+     * 
+     * @return string
+     */
+    public function getAjaxHandlerClass()
+    {
+        return $this->ajaxHandlerClass;
+    }
+
+    /**
+     * Sets whether to call bindToJquery() on the ajax handler
+     * 
+     * @param boolean $bind
+     */
+    public function setBindAjaxHandlerToJquery($bind = true)
+    {
+        $this->ajaxHandlerBindToJquery = $bind;
+        return $this;
+    }
+
+    /**
+     * Checks whether bindToJquery() will be called on the ajax handler
+     * 
+     * @return boolean
+     */
+    public function isAjaxHandlerBoundToJquery()
+    {
+        return $this->ajaxHandlerBindToJquery;
+    }
+
     /**
      * Sets the class name of the js open handler
      * 
@@ -598,6 +646,13 @@ class JavascriptRenderer
             $js .= $this->getJsControlsDefinitionCode($this->variableName);
         }
 
+        if ($this->ajaxHandlerClass) {
+            $js .= sprintf("%s.ajaxHandler = new %s(%s);\n", $this->variableName, $this->ajaxHandlerClass, $this->variableName);
+            if ($this->ajaxHandlerBindToJquery) {
+                 $js .= sprintf("%s.ajaxHandler.bindToJquery();\n", $this->variableName);
+             }
+        }
+
         if ($this->openHandlerUrl !== null) {
             $js .= sprintf("%s.setOpenHandler(new %s(%s));\n", $this->variableName,
                 $this->openHandlerClass,

src/DebugBar/Resources/debugbar.js

@@ -741,4 +741,79 @@ if (typeof(localStorage) == 'undefined') {
     DebugBar.Tab = Tab;
     DebugBar.Indicator = Indicator;
 
+    // ------------------------------------------------------------------
+    
+    /**
+     * AjaxHandler
+     *
+     * Extract data from headers of an XMLHttpRequest and adds a new dataset
+     */
+    var AjaxHandler = PhpDebugBar.AjaxHandler = function(debugbar, headerName) {
+        this.debugbar = debugbar;
+        this.headerName = headerName || 'phpdebugbar';
+    };
+
+    $.extend(AjaxHandler.prototype, {
+
+        /**
+         * Handles an XMLHttpRequest
+         * 
+         * @this {AjaxHandler}
+         * @param {XMLHttpRequest} xhr
+         */
+        handle: function(xhr) {
+            var raw = this.extractDataFromHeaders(xhr);
+            if (!raw) {
+                return;
+            }
+
+            var data = this.parseHeaders(raw);
+            this.debugbar.addDataSet(data.data, data.id);
+        },
+
+        /**
+         * Extract the data as a string from headers of an XMLHttpRequest
+         * 
+         * @this {AjaxHandler}
+         * @param {XMLHttpRequest} xhr
+         * @return {string}
+         */
+        extractDataFromHeaders: function(xhr) {
+            var data = xhr.getResponseHeader(this.headerName);
+            if (!data) {
+                return;
+            }
+            for (var i = 1;; i++) {
+                var header = xhr.getResponseHeader(this.headerName + '-' + i);
+                if (!header) {
+                    break;
+                }
+                data += header;
+            }
+            return decodeURIComponent(data);
+        },
+
+        /**
+         * Parses the string data into an object
+         * 
+         * @this {AjaxHandler}
+         * @param {string} data
+         * @return {string}
+         */
+        parseHeaders: function(data) {
+            return JSON.parse(data);
+        },
+
+        /**
+         * Attaches an event listener to jQuery.ajaxComplete()
+         */
+        bindToJquery: function() {
+            var self = this;
+            $(document).ajaxComplete(function(e, xhr, settings) {
+                self.handle(xhr);
+            });
+        }
+
+    });
+
 })(jQuery);