Simple oauth harness - unable to obtain final access token

[richard10]

Hi,

I have built a very simple OAUTH connection to a canvas instance, but I'm not getting the expected response. Can someone spot where I have gone wrong?

Thanks

A) Start at: http://nick.lms.cm-hosting.com/canvas/login.php 

B) The Oauth initial handshake works, and returns (as specified) back to http://nick.lms.cm-hosting.com/canvas/return.php

C) The PHP $_GET array looks like:

Array (     [code] => 846684a9818d06bf19b639f2f19f5bdbb50188e1440c9e897b7d3abb7250fede81043025b34b3c57a738c5ee111bc52b7f6d3c03a1f502b15b7b7911bc25afb6     [state] => CHECK_THIS )  D) A curl POST is then made to this URL:
https://oup.instructure.com/login/oauth2/token?
code=846684a9818d06bf19b639f2f19f5bdbb50188e1440c9e897b7d3abb7250fede81043025b34b3c57a738c5ee111bc52b7f6d3c03a1f502b15b7b7911bc25afb6
&grant_type=authorization_code
&client_id=130650000000000007
&redirect_uri=http://nick.lms.cm-hosting.com/canvas/return.php&client_secret=ABCDEF (not the real secret)

E) The response returned is: � ]�KO�0 ����� �2 ,IPQ�ix�� �@�JyX^�L��n�ąws��s�{� �<'��M}C:� �;������* � 9 ȏ ���E��K?@��m i���1Am ���w2����!��� �� 0��@ �%� �����s ��aZ �p� B�ט wф�B �@��3f�&� ���2* )K�Ot! �s�6�2�4�I��X���t(�� �s�� �E�����,]�$�V� ����� u� �8�m� �>�_�0�>��*rF �t�� `�|�>

[richard10]

Could the problem be the zip encoding on the curl?

$json = getToken($code, $access_token_url, $client_id, $client_secret, $callback_url);

function getToken($code, $access_token_url, $client_id, $client_secret, $callback_url){
  $curl = curl_init();
 
  $url = $access_token_url."?"
                    ."code=".$code
                    ."&grant_type=authorization_code"
                    ."&client_id=". $client_id
                    ."&redirect_uri=". $callback_url;
 
  printf("<p> url: %s (without client secret) </p>\n",$url);
  $url .= '&client_secret='. $client_secret;
 
  $params = array(
    CURLOPT_URL =>  $url,
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_MAXREDIRS => 10,
    CURLOPT_TIMEOUT => 30,
    CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
    CURLOPT_CUSTOMREQUEST => "POST",
    CURLOPT_NOBODY => false,
    CURLOPT_HTTPHEADER => array(
      "cache-control: no-cache",
      "content-type: application/x-www-form-urlencoded",
      "accept: *",
      "accept-encoding: gzip, deflate",
    ),
  );
 
  curl_setopt_array($curl, $params);
 
  printf("<p> executing curl POST to url");
  $response = curl_exec($curl);
  $err = curl_error($curl);
 
  curl_close($curl);
 
  printf("<p> response (a): \n");
    print_r($response);
  printf("</p>\n");
 
  printf("<p>json return: %s </p>\n",$response);
 
  if ($err) {
    echo "cURL Error #01: " . $err;
  } else {
    $array_response = json_decode($response, true);   
   
    printf("<p>response: %s </p>\n",print_r($array_response,true));
   
    if(array_key_exists("access_token", $array_response)) return $array_response;
    if(array_key_exists("error", $array_response)) echo $array_response["error_description"];
    echo "<p>cURL Error #02: Something went wrong! Please contact admin.</p>";
   
  }
}

[richard10 · Accepted solution]

Ah, yes, it was the zip encoding. The simple exemplar I was using was wrong.