Added base file, basic function to get bearer token and to test search api

Contains a funciton to get the bearer token as described in
https://dev.twitter.com/docs/auth/application-only-auth

As well as a very simple search function that allows querying of the
search api.

Author: jonhurlock

Oauth.php

@@ -0,0 +1,98 @@
+<?php
+/**
+** 	TwitterAppAuth.py
+*
+*	Created by Jon Hurlock on 2013-03-20.
+* 	
+*	Jon Hurlock's Twitter Application-only Authentication App by Jon Hurlock (@jonhurlock)
+*	is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.
+*	Permissions beyond the scope of this license may be available at http://www.jonhurlock.com/.
+*/
+
+
+// fill in your consumer key and consumer secret below
+define('CONSUMER_KEY', 'enter_your_consumer_key_here');
+define('CONSUMER_SECRET', 'enter_your_consumer_secret_here');
+
+	/**
+	*	Get the Bearer Token, this is an implementation of steps 1&2
+	*	from https://dev.twitter.com/docs/auth/application-only-auth
+	*/
+	function get_bearer_token(){
+		// Step 1
+		// step 1.1 - url encode the consumer_key and consumer_secret in accordance with RFC 1738
+		$encoded_consumer_key = urlencode(CONSUMER_KEY);
+		$encoded_consumer_secret = urlencode(CONSUMER_SECRET);
+		// step 1.2 - concatinate encoded consumer, a colon character and the encoded consumer secret
+		$bearer_token = $encoded_consumer_key.':'.$encoded_consumer_secret;
+		// step 1.3 - base64-encode bearer token
+		$base64_encoded_bearer_token = base64_encode($bearer_token);
+		// step 2
+		$url = "https://api.twitter.com/oauth2/token"; // url to send data to for authentication
+		$headers = array( 
+			"POST /oauth2/token HTTP/1.1", 
+			"Host: api.twitter.com", 
+			"User-Agent: jonhurlock Twitter Application-only OAuth App v.1",
+			//"Authorization: Basic ".$base64_encoded_bearer_token."",
+			"Authorization: Basic ".$base64_encoded_bearer_token."",
+			"Content-Type: application/x-www-form-urlencoded;charset=UTF-8", 
+			"Content-Length: 29"
+		); 
+	
+		$ch = curl_init();  // setup a curl
+		curl_setopt($ch, CURLOPT_URL,$url);  // set url to send to
+		curl_setopt($ch, CURLOPT_HTTPHEADER, $headers); // set custom headers
+		curl_setopt($ch, CURLOPT_POST, 1); // send as post
+		curl_setopt($ch, CURLOPT_POSTFIELDS, "grant_type=client_credentials"); // post body/fields to be sent
+		$header = curl_setopt($ch, CURLOPT_HEADER, 1); // send custom headers
+		$httpcode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
+		ob_start();  // start ouput buffering
+		curl_exec ($ch); // execute the curl
+		$retrievedhtml = ob_get_contents(); // grab the retreived html
+		ob_end_clean(); //End buffering and clean output 
+		curl_close($ch); // close the curl
+		$output = explode("\n", $retrievedhtml);
+		$bearer_token = '';
+		
+		foreach($output as $line)
+		{
+			if($pos === false)
+			{
+			}else{
+				$bearer_token = $line;
+			}
+		}
+		
+		$bearer_token = json_decode($bearer_token);
+		return $bearer_token->{'access_token'};
+	}
+	
+	/**
+	* Search
+	* Basic Search of the Search API
+	*/
+	function search_for_a_term($query){
+		$url = "https://api.twitter.com/1.1/search/tweets.json"; // base url
+		$q = $query; // query term
+
+    	$formed_url ='?q='.$q; // fully formed url
+    	$headers = array( 
+    		"GET /1.1/search/tweets.json".$formed_url." HTTP/1.1", 
+    		"Host: api.twitter.com", 
+			"User-Agent: jonhurlock Twitter Application-only OAuth App v.1",
+    		"Authorization: Bearer ".get_bearer_token()."",
+    	);
+		$ch = curl_init();  // setup a curl
+		curl_setopt($ch, CURLOPT_URL,$url.$formed_url);  // set url to send to
+		curl_setopt($ch, CURLOPT_HTTPHEADER, $headers); // set custom headers
+		ob_start();  // start ouput buffering
+		$output = curl_exec ($ch); // execute the curl
+		$retrievedhtml = ob_get_contents(); // grab the retreived html
+		ob_end_clean(); //End buffering and clean output 
+		curl_close($ch); // close the curl
+		return $retrievedhtml;
+	}
+
+	// lets run a search.
+	print search_for_a_term("test");
+	?>