A comprehensive guide to understanding and resolving common API errors.
The server cannot process the request due to a client error (e.g., malformed request syntax, invalid request message framing, or deceptive request routing).
POST /api/users
Content-Type: application/json
{
"userName": "testuser",
"email": "invalid-email"
}
Review the request payload and parameters for any syntax errors, missing fields, or incorrect data formats. Consult the API documentation for the correct structure and expected values.
The request requires user authentication. The client must authenticate itself to get the requested response.
WWW-Authenticate: Bearer realm="example"
Ensure that a valid authentication credential (e.g., API key, OAuth token) is provided in the request headers (typically `Authorization` header). If using tokens, check their validity and expiration.
The server understood the request but refuses to authorize it. The client does not have access privileges to the content.
Verify that the authenticated user or client has the required permissions to access the requested resource or perform the action. Contact the API provider for clarification on access rights.
The server cannot find the requested resource. This may be because the request URI is incorrect or the resource does not exist.
GET /api/v1/products/12345-xyz
Double-check the URL for any typos. Ensure the resource you are trying to access actually exists and that you are using the correct identifier.
The user has sent too many requests in a given amount of time ("rate limiting").
Retry-After: 30
Implement a backoff strategy. Wait for the duration specified in the `Retry-After` header (if provided) before making further requests. Optimize your application to make fewer, more efficient requests.
The server encountered an unexpected condition that prevented it from fulfilling the request. This is a generic server-side error.
This error indicates a problem on the server's end. Contact the API provider or support team with details about your request to help them diagnose the issue.
The server is currently unable to handle the request due to temporary overloading or maintenance of the server.
Retry-After: 3600
This is a temporary issue. Try the request again later. Check the API provider's status page or announcements for information about ongoing maintenance or outages.
The request has succeeded. The information returned with the response is dependent on the method used in the request.
No action is typically required. This indicates a successful operation. Examine the response body for the data returned by the API.
The request has been fulfilled and has resulted in one or more new resources being created. The `Location` header typically contains a URI pointing to the newly created resource.
Location: /api/v1/users/456
No action required. The resource was successfully created. The `Location` header can be used to access the new resource.