Merge pull request #1 from outcompute/add-azure-gcp

Add support for Azure, GCP & templated responses.

Author: outcompute

.gitignore

@@ -1 +1,2 @@
 /vendor
+.DS_Store

LICENSE

@@ -1,6 +1,6 @@
 # CloudMetaData
 A simple PHP library to fetch instance meta data from the link local address of http://169.254.169.254 from within an instance.
-  - Supports [AWS][awsmetadata] & [DigitalOcean][dometadata].
+  - Supports [AWS][awsmetadata], [Azure][azuremetadata], [DigitalOcean][dometadata] & [Google Cloud][gcpmetadata].
   - Results can be cached in a file.
   - Always refreshes metadata after a restart.
 
@@ -10,12 +10,31 @@ The 169.254.169.254 is a link-local address and you can read up more about them
 ### Installation
 Add this line to your composer.json file,
 ```json
-"outcompute/cloudmetadata": "1.4.0"
+"outcompute/cloudmetadata": "1.5.0"
 ```
 and run.
 ```sh
 $ composer update
 ```
+In case you don't want to use composer, you'll have to include all the files, something like this:
+```php
+include_once('src/Cache/AbstractCache.php');
+include_once('src/Cache/File.php');
+include_once('src/CacheFactory.php');
+include_once('src/Provider/AbstractProvider.php');
+include_once('src/Provider/AWS.php');
+include_once('src/Provider/Azure.php');
+include_once('src/Provider/DigitalOcean.php');
+include_once('src/Provider/GCP.php');
+include_once('src/ProviderFactory.php');
+include_once('src/TemplateParser/Base.php');
+include_once('src/TemplateParser/AWS.php');
+include_once('src/TemplateParser/Azure.php');
+include_once('src/TemplateParser/DigitalOcean.php');
+include_once('src/TemplateParser/GCP.php');
+include_once('src/TemplateParserFactory.php');
+include_once('src/MetaData.php');
+```
 
 
 ### How to use
@@ -38,24 +57,44 @@ include_once('vendor/autoload.php');
 $cache = OutCompute\CloudMetaData\CacheFactory::factory('File');
 $cache->directory = dirname(__FILE__);
 $metaObject = new OutCompute\CloudMetaData\MetaData($cache);
-$metaData = $metaObject->get();
+$metaData = $metaObject->get('json');
+var_export($metaData);
+?>
+```
+
+### Templated Responses
+If you've cross cloud deployments and use the metadata in any way, then it'd help to have the metadata in a consistent manner.
+Support has been added for templates which allows you to specify templates and tokens. A few sample tokens have been provided.
+Common and provider agnostic tokens are processed in `src/TemplateParser/Base.php` whereas provider specific tokens are parsed in their specific handlers present in `src/TemplateParser`.
+
+The templates have to be stored in the templates directory, and the file name provided as the second argument to `OutCompute\CloudMetaData\MetaData()::get()`.
+```php
+<?php
+include_once('vendor/autoload.php');
+
+$metaObject = new OutCompute\CloudMetaData\MetaData();
+$metaData = $metaObject->get('json', 'basic.json');
 var_export($metaData);
 ?>
 ```
+The tokens don't have to follow the heirarchy from the templates they are included in and can be any string as long as they are handled in any parser. The initial set of supported tokens seem to follow the heirarchy in basic.json with a dot(.) as a separator, but that is not a strict requirement.
 
+However, if you're contributing to the repository then it'd be great if the tokens followed some structure.
 
 ### TODO
 
- - Add other cloud providers, eg: Google Cloud, Microsoft Azure, Linode, etc.
+ - Add other cloud providers, eg: Linode, etc.
  - Add test cases
  - General improvements
-
+ - Supporting templates in varied configurations and extending the set of supported tokens
 
 License
 ----
 
-GPL v2
+MIT
 
    [awsmetadata]: <http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-instance-metadata.html>
+   [azuremetadata]: <https://docs.microsoft.com/en-us/azure/virtual-machines/windows/instance-metadata-service>
    [dometadata]: <https://developers.digitalocean.com/documentation/metadata/>
+   [gcpmetadata]: <https://cloud.google.com/compute/docs/storing-retrieving-metadata>
    [wikilinklocal]: <https://en.wikipedia.org/wiki/Link-local_address>

README.md

@@ -2,19 +2,20 @@
     "name": "outcompute/cloudmetadata",
     "description": "Get metadata JSON within an instance from 169.254.169.254 across providers.",
     "type": "library",
-    "license": "GPL-2.0",
+    "license": "MIT",
     "authors": [
         {
-            "name": "outcompute",
-            "email": "gkumarrahul@gmail.com"
+        "name": "outcompute",
+        "email": "gkumarrahul@gmail.com"
         }
     ],
     "require": {},
     "autoload": {
-		"psr-4": {
-			"OutCompute\\CloudMetaData\\": "src",
-			"OutCompute\\CloudMetaData\\Cache\\": "src/Cache",
-			"OutCompute\\CloudMetaData\\Provider\\": "src/Provider"
-		}
-	}
+        "psr-4": {
+            "OutCompute\\CloudMetaData\\": "src",
+            "OutCompute\\CloudMetaData\\Cache\\": "src/Cache",
+            "OutCompute\\CloudMetaData\\Provider\\": "src/Provider",
+            "OutCompute\\CloudMetaData\\TemplateParser\\": "src/TemplateParser"
+        }
+    }
 }

composer.json

@@ -1,9 +1,15 @@
 <?php
+/**
+ * The AbstractCache class file.
+ *
+ * @author     outcompute
+ */
+
 namespace OutCompute\CloudMetaData\Cache;
 
 abstract class AbstractCache
 {
-    abstract public function get($key);
-    abstract public function set($key, $data);
+	abstract public function get($key);
+	abstract public function set($key, $data);
 }
 ?>

src/Cache/AbstractCache.php

@@ -3,9 +3,6 @@
  * The File cache class file.
  *
  * @author     outcompute
- * @license    https://www.gnu.org/licenses/old-licenses/gpl-2.0.txt GPL v2
- * @version    1.0.0
- * @since      File available since Release 1.0.0
  */
 
 namespace OutCompute\CloudMetaData\Cache;

src/Cache/File.php

@@ -3,9 +3,6 @@
  * The CacheFactory class file.
  *
  * @author     outcompute
- * @license    https://www.gnu.org/licenses/old-licenses/gpl-2.0.txt GPL v2
- * @version    1.0.0
- * @since      File available since Release 1.0.0
  */
 
 namespace OutCompute\CloudMetaData;

src/CacheFactory.php

@@ -7,9 +7,6 @@
  * in case interface addresses or any other property has been re-assigned.
  *
  * @author     outcompute
- * @license    https://www.gnu.org/licenses/old-licenses/gpl-2.0.txt GPL v2
- * @version    1.0.0
- * @since      File available since Release 1.0.0
  */
 
 namespace OutCompute\CloudMetaData;
@@ -22,15 +19,15 @@ class MetaData
 	private $_data;
 	private $_provider;
 
-	public function __construct($cache = null, $providerFilter = null) {
-		$this->_data = null;
-		$this->_provider = null;
+	public function __construct($cache = NULL, $providerFilter = NULL) {
+		$this->_data = NULL;
+		$this->_provider = NULL;
 		$cacheKey = 'cloudmetadata';
 
 		# List of supported providers to try against
-		$providers = array('AWS', 'DigitalOcean');
+		$providers = array('AWS', 'Azure', 'DigitalOcean', 'GCP');
 
-		if($cache != null) {
+		if($cache != NULL) {
 			$metadata = $cache->get($cacheKey);
 			if($metadata != NULL) {
 				$uptime = floatval(@file_get_contents('/proc/uptime'));
@@ -46,16 +43,16 @@ public function __construct($cache = null, $providerFilter = null) {
 			}
 		}
 
-		if($this->_data == null) {
-			if($providerFilter != null && is_array($providerFilter))
+		if($this->_data == NULL) {
+			if($providerFilter != NULL && is_array($providerFilter))
 				$providers = array_intersect($providers, $providerFilter);
 
 			foreach($providers as $provider) {
 				$this->_data = call_user_func(array(ProviderFactory::factory($provider), 'get'));
 
-				if($this->_data != null) {
+				if($this->_data != NULL) {
 					# The first match has been found, and return after saving to cache, if cache object is set
-					if($cache != null)
+					if($cache != NULL)
 						$cache->set($cacheKey, array('created' => time(), 'provider' => $provider, 'data' => $this->_data));
 					$this->_provider = $provider;
 					break;
@@ -64,9 +61,22 @@ public function __construct($cache = null, $providerFilter = null) {
 		}
 	}
 
-	public function get($format = 'array')
-	{
+	public function get($format = 'array', $templateName = NULL) {
 		$response = array('provider' => $this->_provider, 'metadata' => $this->_data);
+		$templatedResponse = NULL;
+
+		if($templateName != NULL) {
+			$parsedResponseObject = NULL;
+			$templatePath = rtrim(__DIR__, '/').'/../templates/'.basename($templateName);
+			if(file_exists($templatePath))
+				$templateObject = json_decode(file_get_contents($templatePath), true);
+			if($templateObject != NULL) {
+				$parserObject = TemplateParserFactory::factory($response['provider'], $response['metadata']);
+				$parsedResponseObject = $this->_parseTemplate($templateObject, $parserObject);
+			}
+			$response = $parsedResponseObject;
+		}
+
 		switch($format) {
 			case 'json':
 				return json_encode($response, JSON_PRETTY_PRINT);
@@ -76,5 +86,23 @@ public function get($format = 'array')
 				break;
 		}
 	}
+
+	private function _parseTemplate($templateObject, $parserObject) {
+		foreach($templateObject as $k => $v) {
+			switch(gettype($v)) {
+				case "string":
+					$templateObject[$k] = $parserObject->get($v);
+				break;
+				case "array":
+				case "object":
+					$templateObject[$k] = $this->_parseTemplate($v, $parserObject);
+				break;
+				default:
+					$templateObject[$k] = $v;
+				break;
+			}
+		}
+		return $templateObject;
+	}
 }
 ?>

src/MetaData.php

@@ -5,9 +5,6 @@
  * This fetches the metadata from the Amazon meta data service
  *
  * @author     outcompute
- * @license    https://www.gnu.org/licenses/old-licenses/gpl-2.0.txt GPL v2
- * @version    1.0.0
- * @since      File available since Release 1.0.0
  */
 
 namespace OutCompute\CloudMetaData\Provider;
@@ -26,10 +23,15 @@ public function get() {
         # Furthermore we need to segregate them because although AWS documentation does mention that all keys ending in '/'
         # have expansions, the keys reported at http://169.254.169.254/latest/ don't end in '/'
         $keys = array('dynamic/', 'meta-data/', 'user-data/');
-        foreach($keys as $key)
-            $response[trim($key, '/')] = $this->_recurse(self::BASE, $key);
+        $allValuesNull = true;
+        foreach($keys as $key) {
+            $value = $this->_recurse(self::BASE, $key);
+            $response[trim($key, '/')] = $value;
+            if($value != NULL)
+                $allValuesNull = false;
+        }
 
-        return $response;
+        return $allValuesNull == true ? NULL : $response;
     }
 
     private function _recurse($url, $key) {

src/Provider/AWS.php

@@ -3,9 +3,6 @@
  * The AbstractProvider class file.
  *
  * @author     outcompute
- * @license    https://www.gnu.org/licenses/old-licenses/gpl-2.0.txt GPL v2
- * @version    1.0.0
- * @since      File available since Release 1.0.0
  */
 
 namespace OutCompute\CloudMetaData\Provider;
@@ -20,13 +17,17 @@ public function connect($url, $options = array())
         if(function_exists('curl_init')) {
             $curl = curl_init($url);
             curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
+            foreach($options as $opt)
+                curl_setopt($curl, $opt['option'], $opt['value']);
             $result = curl_exec($curl);
             $info = curl_getinfo($curl);
             $errorStr = curl_error($curl);
             curl_close($curl);
 
             if($info['http_code'] == 200)
                 return $result;
+            else
+                return NULL;
         } else {
             throw new \Exception("OutCompute\CloudMetaData\Provider\AbstractProvider : curl not installed. Failed to connect to $url");
         }