我在这里阅读了关于如何处理过期访问令牌的facbeook博客文章:https://developers.facebook.com/blog/post/2011/05/13/how-to--handle-expired-access-tokens/
但有些事情对我来说并不清楚,这让我很难取得进步。我列出了博客中的示例代码和我自己的php代码。我最想知道我需要对我的代码做出哪些更改,以便博客中的代码可以在我自己的代码中运行。我也对博客中的特定代码有一些疑问。对于初学者来说,$ _REQUEST [“code”]来自哪里?
如果您查看我的代码,您会看到我正在尝试向用户发送通知,我会事先得到应用访问令牌,然后进行api调用以及随之发送访问令牌;但是在示例代码中,使用curl_file_get_contents()而不是$ facebook-> api进行图形调用,我该怎么办? $ facebook-> api是否会返回与curl_file_get_contents()相同的响应?因为示例代码检查该错误的响应并重定向(如果有)。
//PHP SAMPLE CODE FROM THE BLOG
<?php
$app_id = "YOUR_APP_ID";
$app_secret = "YOUR_APP_SECRET";
//IS THIS SUPPOSED TO BE MY CANVAS APP URL?
$my_url = "YOUR_POST_LOGIN_URL";
// known valid access token stored in a database
$access_token = "YOUR_STORED_ACCESS_TOKEN";
//WHERE IS THIS $CODE VARIABLE COMING FROM?
$code = $_REQUEST["code"];
if (isset($code)) {
$token_url="https://graph.facebook.com/oauth/access_token?client_id="
. $app_id . "&redirect_uri=" . urlencode($my_url)
. "&client_secret=" . $app_secret
. "&code=" . $code . "&display=popup";
$response = file_get_contents($token_url);
$params = null;
parse_str($response, $params);
$access_token = $params['access_token'];
}
// ATTEMPT TO QUERY THE GRAPH
$graph_url = "https://graph.facebook.com/me?"
. "access_token=" . $access_token;
$response = curl_get_file_contents($graph_url);
$decoded_response = json_decode($response);
//CHECK FOR ERRORS
if ($decoded_response->error) {
// check to see if this is an oAuth error:
if ($decoded_response->error->type== "OAuthException") {
// Retrieving a valid access token.
$dialog_url= "https://www.facebook.com/dialog/oauth?"
. "client_id=" . $app_id
. "&redirect_uri=" . urlencode($my_url);
echo("<script> top.location.href='" . $dialog_url
. "'</script>");
}
else {
echo "other error has happened";
}
}
else {
// success
echo("success" . $decoded_response->name);
echo($access_token);
}
// note this wrapper function exists in order to circumvent PHP’s
//strict obeying of HTTP error codes. In this case, Facebook
//returns error code 400 which PHP obeys and wipes out
//the response.
function curl_get_file_contents($URL) {
$c = curl_init();
curl_setopt($c, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($c, CURLOPT_URL, $URL);
$contents = curl_exec($c);
$err = curl_getinfo($c,CURLINFO_HTTP_CODE);
curl_close($c);
if ($contents) return $contents;
else return FALSE;
}
?>
//MY PHP
$token_url ="https://graph.facebook.com/oauth/access_token?" .
"client_id=" . $APP_ID .
"&client_secret=" . $APP_SECRET .
"&grant_type=client_credentials";
$app_token = file_get_contents($token_url);
$app_token = str_replace("access_token=", "", $app_token);
$data = array(
'href'=> 'https://apps.facebook.com/thebringernetwork/',
'access_token'=> $app_token,
'template'=> 'test'
);
// HOW DO I USE THAT ERROR CHECKING CODE AT THIS POINT?
$facebook->api('/16xxxxx3/notifications', 'post', $data);