HTTP Status Code 424 – Failed Dependency

The HTTP status code 424 Failed Dependency indicates that the request failed because it depended on another request that also failed. This status code is typically used in the context of WebDAV (Web Distributed Authoring and Versioning) when performing operations on resources that are interdependent.

Examples

Example 1: WebDAV LOCK Request Failure

        LOCK /example/resource HTTP/1.1
        Host: www.example.com
        Timeout: Infinite, Second-4100000000
        

In this scenario, a client attempts to lock a resource but the lock depends on a previous lock request that failed. When the server tries to process this LOCK request, it encounters a dependency issue and returns a 424 status code:

        HTTP/1.1 424 Failed Dependency
        Content-Type: application/xml

        <D:error xmlns:D="DAV:">
            <D:failed-dependency/>
        </D:error>
        

Example 2: PROPPATCH Request Failure

        PROPPATCH /example/resource HTTP/1.1
        Host: www.example.com
        Content-Type: text/xml; charset="utf-8"
        Content-Length: xxxx

        <?xml version="1.0" encoding="utf-8" ?>
        <D:propertyupdate xmlns:D="DAV:">
            <D:set>
                <D:prop>
                    <D:custom-property>value</D:custom-property>
                </D:prop>
            </D:set>
        </D:propertyupdate>
        

In this example, a client issues a PROPPATCH request to change a property’s value on a resource. If this operation depends on a prior operation (such as a previous PROPPATCH or LOCK) that failed, the server will respond with a 424 status code:

        HTTP/1.1 424 Failed Dependency
        Content-Type: application/xml

        <D:error xmlns:D="DAV:">
            <D:failed-dependency/>
        </D:error>
        

Example 3 failed Scenario

# Client sends a request example.
GET /example HTTP/1.1
Host: www.example.com

# Server Response
HTTP/1.1 424 424 Failed Dependency
Date: Wed, 09 Oct 2024 23:06:36 GMT
Server: ExampleServer/1.0
Content-Type: application/json

{
    "error": "Description of the error for 424"
}

Example 4: Heres Another Scenario

# Client sends another example request.
POST /another-example HTTP/1.1
Host: www.example.com

# Server Response
HTTP/1.1 424 424 Failed Dependency
Date: Wed, 09 Oct 2024 23:06:36 GMT
Server: ExampleServer/1.0
Content-Type: application/json

{
    "error": "Detailed message for 424"
}

Summary

The 424 Failed Dependency status code is used to indicate that a request cannot be processed because it is reliant on another request that has failed. This code is mainly relevant in WebDAV operations, where multiple requests might be part of a larger transaction. Understanding the role of dependency in these requests is crucial for diagnosing issues when this status code is encountered.