Creation of an Object storage container should include a "Content-Length: 0" header

[dmsimard]

The only case where a PUT request does not require a Content-Length header is for a chunked transfer of an object.
In that case, a client application must specify a header Transfer-Encoding: chunked in the request and the web server will pass the request through.

When creating a container with Openstack.net, a PUT request is sent with the following headers:

Content-Type: application/json
Accept: application/json
User-Agent: openstack.net/1.3.0.0
X-Auth-Token: [deleted]
Host: [Swift endpoint]

Since no Content-Length headers are set, this is a problem when the object storage endpoint is located behind load balancers or web servers that are standards-compliant (examples that come to mind: Apache, Nginx).

The header is provided in the examples provided by the documentation quoted in the comments in the code.
See:

• https://github.com/openstacknetsdk/openstack.net/blob/master/src/corelib/Core/Providers/IObjectStorageProvider.cs#L83
• http://docs.openstack.org/api/openstack-object-storage/1.0/content/PUT_createContainer_v1__account___container__storage_container_services.html

This is also the behavior of the official Swift client library - python-swiftclient:

curl -i http://[Swift endpoint]/v1/AUTH_[...]/container -X PUT -H "Content-Length: 0" -H "X-Auth-Token: [token]"

swift-proxy does not enforce this header strictly for the creation of containers - it is something that it should do but cannot be done without breaking backwards compatibility and that is why it still behaves this way.

[sharwell]

Thanks for reporting this. Can you try the following and let me know if it works for you?

1. Create a new class which extends CloudFilesProvider

2. Override the BuildDefaultRequestSettings method:

   protected override RequestSettings BuildDefaultRequestSettings(IEnumerable<HttpStatusCode> non200SuccessCodes)
   {
       RequestSettings settings = base.BuildDefaultRequestSettings(non200SuccessCodes);
       settings.AllowZeroContentLength = true;
       return settings;
   }

3. Use the custom implementation instead of CloudFilesProvider in your code.

[UltraBac]

HI. I am the end-user that reported this issue.
Our project is written in C++ using CLI. I've never overridden any functions in .NET, and I couldn't find the instructions for building openstack.net for Visual Studio. Any pointers you might be able to give for either would be appreciated, and I would be happy to try your suggestion.

[sharwell]

@BritBlaster Thank you for taking the time to report the issue you found. I believe the following class can be used in place of CloudFilesProvider in your code to work around the described issue. You may need to tweak the constructor to match the CloudFilesProvider you are currently using in your code.

using namespace System::Collections::Generic;
using namespace System::Net;
using namespace net::openstack::Core::Providers;
using namespace net::openstack::Providers::Rackspace;
using namespace JSIStudios::SimpleRESTServices::Client;

ref class CloudFilesProviderWithContentType : CloudFilesProvider
{
public:
    CloudFilesProviderWithContentType(IIdentityProvider^ identityProvider)
        : CloudFilesProvider(identityProvider)
    {
    }

protected:
    virtual RequestSettings^ BuildDefaultRequestSettings(IEnumerable<HttpStatusCode>^ non200SuccessCodes) override
    {
        RequestSettings^ settings = CloudFilesProvider::BuildDefaultRequestSettings(non200SuccessCodes);
        settings->AllowZeroContentLength = true;
        return settings;
    }
};

[UltraBac]

Thanks so much for the help. I modified the constructor, as suggested, to the following (using explicit naming):

ref class CloudFilesProviderWithContentType : net::openstack::Providers::Rackspace::CloudFilesProvider
{
public:
    CloudFilesProviderWithContentType(net::openstack::Core::Domain::CloudIdentity ^defaultIdentity,
                                      System::String ^defaultRegion,
                                      net::openstack::Core::Providers::IIdentityProvider^ identityProvider,
                                      JSIStudios::SimpleRESTServices::Client::IRestService ^restService
                                      ) : net::openstack::Providers::Rackspace::CloudFilesProvider(defaultIdentity, defaultRegion, identityProvider, restService)
    {
    }

and I verified that the header "Content-Length: 0" was added in the http request, and the response was:
HTTP/1.1 201 Created
Yay, success! Thanks again.

[dmsimard]

Great news. Thanks for your help @sharwell.