# API Basics

The versioning of each API is independent of the document version.

# Requirements

All APIs require an API Key in the header when making a call. If you haven't issued an API Key, you can issue one in [Generate API key](dashboard-generate-api-key).

| Field     | Type   | Description |
| :-------- | :----- | :---------- |
| x-api-key | String | API Key     |

# Response Structure

All API responses follow the structure of the response object below.

<Table align={["left","left","left"]}>
  <thead>
    <tr>
      <th>
        Field
      </th>

      <th>
        Type
      </th>

      <th>
        Description
      </th>
    </tr>
  </thead>

  <tbody>
    <tr>
      <td>
        detail
      </td>

      <td>
        String
      </td>

      <td>
        Message value according to the API call result.
      </td>
    </tr>

    <tr>
      <td>
        result
      </td>

      <td>
        Object
      </td>

      <td>
        Result value according to the API call.\
        (Provided in case of a successful API call)
      </td>
    </tr>
  </tbody>
</Table>

# Common Error Responses

The following are common error responses that can occur when making API calls.

1. **401 Unauthorized**

* API Key is missing or invalid
  ```json
  {
    "detail": "Unauthorized"
  }
  ```

2. **403 Plan is expired**

* Plan usage period has expired
  ```json
  {
    "detail": "Plan is expired"
  }
  ```

3. **403 Rate limit exceeded**

* API call count has exceeded the defined Rate limit
  ```json
  {
    "detail": "Rate limit exceeded"
  }
  ```

4. **403 Quota exceeded**

* API call count has exceeded the defined Quota
  ```json JSON
  {
    "detail": "Quota exceeded"
  }
  ```

# Versioning

By default, the versions for APIs and Callbacks are managed separately. For example, GET v1/A and GETv2/B APIs can have different versions.

The versioning policy for APIs and Callbacks is as follows:

### No version upgrade

* Adding new columns to the response object

### Version upgrade

* Changing the column names in the response object
* Changing the values of specific columns in the response object (data type, ENUM values, etc.)
* Changing the structure of the response object
* Adding new features that are not supported in previous versions