# Linkedin API - Exchange Authorization by Access Code
**URL:** https://discourse.cakephp.org/t/linkedin-api-exchange-authorization-by-access-code/2788
**Category:** Uncategorized
**Created:** [June 27, 2017, 9:08pm UTC](https://discourse.cakephp.org/t/linkedin-api-exchange-authorization-by-access-code/2788 "2017-06-27T21:08:29Z")
**Posts on this page:** 1
**Page:** 1
### Author:  [@Marcelo](https://discourse.cakephp.org/u/Marcelo)
#### Post date: [June 27, 2017, 9:08pm UTC](https://discourse.cakephp.org/t/linkedin-api-exchange-authorization-by-access-code/2788/1 "2017-06-27T21:08:29Z")
I have been developing an app who will pulling data from linkedin users. It will happened right after of the login by the user.
At moment, I reached the level to get AUTHORIZATION CODE, but I have not exchange the AUTUHORIZATION CODE by the ACCESS CODE
I did make a request following these steps
1 - The method “auth()” make a request to obtain AUTHORIZATION CODE
2 - The method redirect the user to another method called “callback()”, wich I’m trying exchange the AUTHORIZATION CODE by ACCESS TOKEN. However, a return page display an error 400
How can I get this ACCESS CODE? Where I did make a mistake?
MYCODE
```
<<< $this-\>responseType,
‘client\_id’ =\> $this-\>clientID,
‘scope’ =\> $this-\>scope,
‘state’ =\> $this-\>state,
‘redirect\_uri’ =\> $this-\>callbackURL,
];
$this-\>redirect('[https://www.linkedin.com/oauth/v2/authorization?’](https://www.linkedin.com/oauth/v2/authorization?'))
OBS: Aqui não está descrito o caminho completo, mas essa fase está
funcionando e o código de autorização está sendo exibido no HEADER e
direcionando para o método Callback
}
public function callback()
{
// if( !empty( $this-\>request-\>query[‘code’] ) && !empty( $this-\>request-\>query[‘state’] ) && ( $this-\>request-\>query[‘state’] == $this-\>state ) )
//{
$params = [
‘grant\_type’ =\> $this-\>grantType,
‘client\_id’ =\> $this-\>clientID,
‘client\_secret’ =\> $this-\>clientSecret,
‘code’ =\> $this-\>request-\>query[‘code’],
‘redirect\_uri’ =\> $this-\>callbackURL,
];
```
$http = new Client();
$response = $http->post('https://www.linkedin.com/uas/oauth2/accessToken?', $params);
$token = json_decode($response->body);
debug($response);
$user_linkedin = $this->_fetchLinkedin('/v1/people/~:(firstName,lastName,emailAddress)', $token->access_token);
if( !empty( $user_linkedin->emailAddress ) )
{
$this->loadModel('Users');
$password = Security::hash($user_linkedin->emailAddress, 'sha1', true);
$user = $this->Users->findByEmail($user_linkedin->emailAddress)->first();
if( empty( $user ) )
{
$data = [
'email' => $user_linkedin->emailAddress,
'password' => $password,
'fname' => $user_linkedin->firstName,
'lname' => $user_linkedin->lastName
];
$user = $this->Users->newEntity($data);
$this->Users->save($user);
unset($data['password']);
$this->Auth->setUser($data);
$this->request->session()->delete("Auth.User.password");
$this->redirect($this->Auth->redirectUrl());
}else{
$user = $user->toArray();
$data = ['id' => $user['id'], 'email' => $user['email'], 'fname' => $user['fname']];
$this->Auth->setUser($data);
$this->request->session()->delete("Auth.User.password");
$this->redirect($this->Auth->redirectUrl());
}
}
```
}
protected function \_fetchLinkedin($resource, $access\_token = ‘’) {
$params = [
‘oauth2\_access\_token’ =\> $access\_token,
‘format’ =\> ‘json’,
];
$http = new Client();
$response = $http-\>get(‘[https://api.linkedin.com](https://api.linkedin.com)’ . $resource, $params);
```
return json_decode($response->body);
```
}\>\>\>\>
ERROR DISPLAY
