alchemyapi.php

<?php

class AlchemyAPI {
	
	private $_api_key;
	private $_ENDPOINTS;
    private $_BASE_URL = 'http://access.alchemyapi.com/calls';

	public function AlchemyAPI() {
		//Load the API Key from api_key.txt
		$key = trim(file_get_contents("api_key.txt"));
	
		if (!$key) {
			//Keys should not be blank
			echo 'The api_key.txt file appears to be blank, please copy/paste your API key in the file: api_key.txt', PHP_EOL;
			echo 'If you do not have an API Key from AlchemyAPI, please register for one at: http://www.alchemyapi.com/api/register.html', PHP_EOL;
			file_put_contents('api_key.txt','');
			exit(1);
		}

		if (strlen($key) != 40) {
			echo strlen($key), PHP_EOL;
			//Keys should be 40 characters long
			echo 'It appears that the key in api_key.txt is invalid. Please make sure the file only includes the API key, and it is the correct one.', PHP_EOL;
			exit(1);
		}

		$this->_api_key = $key;


		//Initialize the API Endpoints
		$this->_ENDPOINTS['sentiment']['url'] = '/url/URLGetTextSentiment';
		$this->_ENDPOINTS['sentiment']['text'] = '/text/TextGetTextSentiment';
		$this->_ENDPOINTS['sentiment']['html'] = '/html/HTMLGetTextSentiment';
		$this->_ENDPOINTS['sentiment_targeted']['url'] = '/url/URLGetTargetedSentiment';
		$this->_ENDPOINTS['sentiment_targeted']['text'] = '/text/TextGetTargetedSentiment';
		$this->_ENDPOINTS['sentiment_targeted']['html'] = '/html/HTMLGetTargetedSentiment';
		$this->_ENDPOINTS['author']['url'] = '/url/URLGetAuthor';
		$this->_ENDPOINTS['author']['html'] = '/html/HTMLGetAuthor';
		$this->_ENDPOINTS['keywords']['url'] = '/url/URLGetRankedKeywords';
		$this->_ENDPOINTS['keywords']['text'] = '/text/TextGetRankedKeywords';
		$this->_ENDPOINTS['keywords']['html'] = '/html/HTMLGetRankedKeywords';
		$this->_ENDPOINTS['concepts']['url'] = '/url/URLGetRankedConcepts';
		$this->_ENDPOINTS['concepts']['text'] = '/text/TextGetRankedConcepts';
		$this->_ENDPOINTS['concepts']['html'] = '/html/HTMLGetRankedConcepts';
		$this->_ENDPOINTS['entities']['url'] = '/url/URLGetRankedNamedEntities';
		$this->_ENDPOINTS['entities']['text'] = '/text/TextGetRankedNamedEntities';
		$this->_ENDPOINTS['entities']['html'] = '/html/HTMLGetRankedNamedEntities';
		$this->_ENDPOINTS['category']['url']  = '/url/URLGetCategory';
		$this->_ENDPOINTS['category']['text'] = '/text/TextGetCategory';
		$this->_ENDPOINTS['category']['html'] = '/html/HTMLGetCategory';
		$this->_ENDPOINTS['relations']['url']  = '/url/URLGetRelations';
		$this->_ENDPOINTS['relations']['text'] = '/text/TextGetRelations';
		$this->_ENDPOINTS['relations']['html'] = '/html/HTMLGetRelations';
		$this->_ENDPOINTS['language']['url']  = '/url/URLGetLanguage';
		$this->_ENDPOINTS['language']['text'] = '/text/TextGetLanguage';
		$this->_ENDPOINTS['language']['html'] = '/html/HTMLGetLanguage';
		$this->_ENDPOINTS['text_clean']['url']  = '/url/URLGetText';
		$this->_ENDPOINTS['text_clean']['html'] = '/html/HTMLGetText';
		$this->_ENDPOINTS['text_raw']['url']  = '/url/URLGetRawText';
		$this->_ENDPOINTS['text_raw']['html'] = '/html/HTMLGetRawText';
		$this->_ENDPOINTS['text_title']['url']  = '/url/URLGetTitle';
		$this->_ENDPOINTS['text_title']['html'] = '/html/HTMLGetTitle';
		$this->_ENDPOINTS['feeds']['url']  = '/url/URLGetFeedLinks';
		$this->_ENDPOINTS['feeds']['html'] = '/html/HTMLGetFeedLinks';
		$this->_ENDPOINTS['microformats']['url']  = '/url/URLGetMicroformatData';
		$this->_ENDPOINTS['microformats']['html'] = '/html/HTMLGetMicroformatData';
	}

	public function entities($flavor, $data, $options) {
		//Make sure this request supports the flavor
		if (!array_key_exists($flavor, $this->_ENDPOINTS['entities'])) {
			return array('status'=>'ERROR','statusInfo'=>'Entity extraction for ' . $flavor . ' not available');
		}

		//Add the URL encoded data to the options and analyze
		$options[$flavor] = rawurlencode($data);
		return $this->analyze($this->_ENDPOINTS['entities'][$flavor], $options);
	}


	public function keywords($flavor, $data, $options) {
		//Make sure this request supports the flavor
		if (!array_key_exists($flavor, $this->_ENDPOINTS['keywords'])) {
			return array('status'=>'ERROR','statusInfo'=>'Keyword extraction for ' . $flavor . ' not available');
		}

		//Add the URL encoded data to the options and analyze
		$options[$flavor] = rawurlencode($data);
		return $this->analyze($this->_ENDPOINTS['keywords'][$flavor], $options);
	}


	public function sentiment($flavor, $data, $options) {
		//Make sure this request supports the flavor
		if (!array_key_exists($flavor, $this->_ENDPOINTS['sentiment'])) {
			return array('status'=>'ERROR','statusInfo'=>'Sentiment analysis for ' . $flavor . ' not available');
		}

		//Add the URL encoded data to the options and analyze
		$options[$flavor] = rawurlencode($data);
		return $this->analyze($this->_ENDPOINTS['sentiment'][$flavor], $options);
	}


	public function sentiment_targeted($flavor, $data, $target, $options) {
		//Make sure this request supports the flavor
		if (!array_key_exists($flavor, $this->_ENDPOINTS['sentiment'])) {
			return array('status'=>'ERROR','statusInfo'=>'Sentiment analysis for ' . $flavor . ' not available');
		}

		if (!$target) {
			return array('status'=>'ERROR','statusInfo'=>'targeted sentiment requires a non-null target');
		}

		//Add the URL encoded data to the options and analyze
		$options[$flavor] = rawurlencode($data);
		return $this->analyze($this->_ENDPOINTS['sentiment'][$flavor], $options);
	}


	public function concepts($flavor, $data, $options) {
		//Make sure this request supports the flavor
		if (!array_key_exists($flavor, $this->_ENDPOINTS['concepts'])) {
			return array('status'=>'ERROR','statusInfo'=>'Concept tagging for ' . $flavor . ' not available');
		}

		//Add the URL encoded data to the options and analyze
		$options[$flavor] = rawurlencode($data);
		return $this->analyze($this->_ENDPOINTS['concepts'][$flavor], $options);
	}


	public function author($flavor, $data, $options) {
		//Make sure this request supports the flavor
		if (!array_key_exists($flavor, $this->_ENDPOINTS['author'])) {
			return array('status'=>'ERROR','statusInfo'=>'Author extration for ' . $flavor . ' not available');
		}

		//Add the URL encoded data to the options and analyze
		$options[$flavor] = rawurlencode($data);
		return $this->analyze($this->_ENDPOINTS['author'][$flavor], $options);
	}


	public function category($flavor, $data, $options) {
		//Make sure this request supports the flavor
		if (!array_key_exists($flavor, $this->_ENDPOINTS['category'])) {
			return array('status'=>'ERROR','statusInfo'=>'Text categorization for ' . $flavor . ' not available');
		}

		//Add the URL encoded data to the options and analyze
		$options[$flavor] = rawurlencode($data);
		return $this->analyze($this->_ENDPOINTS['category'][$flavor], $options);
	}
	

	public function relations($flavor, $data, $options) {
		//Make sure this request supports the flavor
		if (!array_key_exists($flavor, $this->_ENDPOINTS['relations'])) {
			return array('status'=>'ERROR','statusInfo'=>'Relation extraction for ' . $flavor . ' not available');
		}

		//Add the URL encoded data to the options and analyze
		$options[$flavor] = rawurlencode($data);
		return $this->analyze($this->_ENDPOINTS['relations'][$flavor], $options);
	}

	
	public function language($flavor, $data, $options) {
		//Make sure this request supports the flavor
		if (!array_key_exists($flavor, $this->_ENDPOINTS['language'])) {
			return array('status'=>'ERROR','statusInfo'=>'Language detection for ' . $flavor . ' not available');
		}

		//Add the URL encoded data to the options and analyze
		$options[$flavor] = rawurlencode($data);
		return $this->analyze($this->_ENDPOINTS['language'][$flavor], $options);
	}

	
	public function text_clean($flavor, $data, $options) {
		//Make sure this request supports the flavor
		if (!array_key_exists($flavor, $this->_ENDPOINTS['text_clean'])) {
			return array('status'=>'ERROR','statusInfo'=>'Clean text extraction for ' . $flavor . ' not available');
		}

		//Add the URL encoded data to the options and analyze
		$options[$flavor] = rawurlencode($data);
		return $this->analyze($this->_ENDPOINTS['text_clean'][$flavor], $options);
	}


	public function text_raw($flavor, $data, $options) {
		//Make sure this request supports the flavor
		if (!array_key_exists($flavor, $this->_ENDPOINTS['text_raw'])) {
			return array('status'=>'ERROR','statusInfo'=>'Raw text extraction for ' . $flavor . ' not available');
		}

		//Add the URL encoded data to the options and analyze
		$options[$flavor] = rawurlencode($data);
		return $this->analyze($this->_ENDPOINTS['text_raw'][$flavor], $options);
	}


	public function text_title($flavor, $data, $options) {
		//Make sure this request supports the flavor
		if (!array_key_exists($flavor, $this->_ENDPOINTS['text_title'])) {
			return array('status'=>'ERROR','statusInfo'=>'Title text extraction for ' . $flavor . ' not available');
		}

		//Add the URL encoded data to the options and analyze
		$options[$flavor] = rawurlencode($data);
		return $this->analyze($this->_ENDPOINTS['text_title'][$flavor], $options);
	}


	public function microformats($flavor, $data, $options) {
		//Make sure this request supports the flavor
		if (!array_key_exists($flavor, $this->_ENDPOINTS['microformats'])) {
			return array('status'=>'ERROR','statusInfo'=>'Microformat parsing for ' . $flavor . ' not available');
		}

		//Add the URL encoded data to the options and analyze
		$options[$flavor] = rawurlencode($data);
		return $this->analyze($this->_ENDPOINTS['microformats'][$flavor], $options);
	}


	public function feeds($flavor, $data, $options) {
		//Make sure this request supports the flavor
		if (!array_key_exists($flavor, $this->_ENDPOINTS['feeds'])) {
			return array('status'=>'ERROR','statusInfo'=>'Feed detection for ' . $flavor . ' not available');
		}

		//Add the URL encoded data to the options and analyze
		$options[$flavor] = rawurlencode($data);
		return $this->analyze($this->_ENDPOINTS['feeds'][$flavor], $options);
	}


	private function analyze($url, $params) {
		//Insert the base URL
		$url = $this->_BASE_URL . $url;

		//Add the API Key and set the output mode to JSON
		$url = $url . '?apikey=' . $this->_api_key . '&outputMode=json';

		//Add the remaining parameters
		foreach($params as $key => $value) {
			$url = $url . '&' . $key . '=' . $value;
		}
		
		//Create the HTTP header
		$header = array('http' => array('method' => 'POST', 'Content-type'=> 'application/x-www-form-urlencoded'));
		
		//Fire off the HTTP Request
		try {
			$fp = @fopen($url, 'rb',false, stream_context_create($header));
			$response = @stream_get_contents($fp);
			fclose($fp);
			return json_decode($response, true);
		} catch (Exception $e) {
			return array('status'=>'ERROR', 'statusInfo'=>'Network error');
		}
	}
}

//Run simple script to save API key if run from the command line
if (php_sapi_name() == 'cli') {
	if (count($argv) == 2) {
		if (strlen($argv[1]) == 40) {
			file_put_contents('api_key.txt',$argv[1]);
			echo 'Key: ' . $argv[1] . ' successfully written to api_key.txt', PHP_EOL;
		} else {
			echo 'Invalid key! Make sure it is 40 characters in length', PHP_EOL;
		}
	}
}


?>