在Codeigniter中生成JSON查询结果

Question

So i have database table named usermeta and have table structure like this :

-----------------------------------------------------------
| ummeta_id | user_id | meta_key    | meta_value          |
-----------------------------------------------------------
| 1         | 1       | fullname    | John Doe            |
| 2         | 1       | birthplace  | New York            |
| 3         | 1       | birthdate   | 1990/01/01          |
| 4         | 1       | mobile      | 0812-3456-7890      |
| 5         | 1       | email       | [e-mail]   |
| 6         | 2       | fullname    | Jon Wick            |
| 7         | 2       | birthplace  | Washington DC       |
| 8         | 2       | birthdate   | 1985/10/21          |
| 9         | 2       | mobile      | 0890-1234-5678      |
| 10        | 2       | email       | [e-mail]   |

And i try to generate json data for all data from this database using Codeigniter (v 3.1.9) using Controller and Model.

This is my Model (model name: db_usermeta)

function userslist()
{
   $query = $this->db->select('*')
                     ->from('usermeta')
                     ->get();
   return $query->result();
}

This is my Controller

public function userlist()
{
   header('Content-Type: application/json; charset=utf-8');
   $query = $this->db_usermeta->userslist();
   $json_data = array();
   foreach ($query as $key)
   {
      $json_data[$key->meta_key] = $key->meta_value;
   }
   echo json_encode($json_data);
}

The result when i open using my browser to check the json data using web developer tool is only show last record, in this case only show data from user_id 2, like this:

{
  "fullname":"John Wick",
  "birthplace":"Washinton DC",
  "birthdate":"1985/10/21",
  "mobile":"0890-1234-5678",
  "email":"[e-mail]"
}

What I want to achieve is to show all json data nested like this:

"data": [
  {
    "fullname":"John Doe",
    "birthplace":"New York",
    "birthdate":"1990/01/01",
    "mobile":"0812-3456-7890",
    "email":"[e-mail]"
  },
  {
    "fullname":"John Wick",
    "birthplace":"Washinton DC",
    "birthdate":"1985/10/21",
    "mobile":"0890-1234-5678",
    "email":"[e-mail]"
  }
]

How can i achieve this? Did I make a mistake on my controller and model. I really appreciate your help.

Answer 1

your $key->meta_key is overwriting for every record. that's why only last record appeared. You don't actually need to loop through to get json data.

public function userlist()
{
   header('Content-Type: application/json; charset=utf-8');
   $query = $this->db_usermeta->userslist();
   $json_data = array(array());
   $user_id_map = array();
   $index = 0;
   foreach ($query as $key)
   {
        if(!isset($user_id_map[$key->user_id])){
            $user_id_map[$key->user_id] = $index++;
        }
        $currentIndex = $user_id_map[$key->user_id];
        $json_data[$currentIndex][$key->meta_key] = $key->meta_value;
   }
   echo json_encode($json_data);
}

just change your controller code to this and this will return json data.