REST API design: Tell the server to "refresh" a set of resources

Question

We have a resource on a REST server ie

• /someResources/1
• /someResources/2
• /someResources/3

where "someResource" is a server representation of a distributed object far away.

We want to tell the server to "refresh" its representation of that "distributed object" by looking at it out in the network & updating the server's cache ie we can not simply PUT the new value.

What is the clean REST way to this ?

a) Is it to POST to a /refreshes/ a new "refresh request" ?

b) Is it to PUT (with a blank document) to http://ip/someResources ?

c) Something else ?

I like (a) as it will give us an id to identify & track the refresh command but worried that we are creating too many resources?

Thanks

Kieran

Answer 1

HTTP caching seems to allow for this. http://www.w3.org/Protocols/rfc2616/rfc2616-sec13.html#sec13.1.6

Set the header max-age=0 and this will instruct the server that the client wants a new version. This way you can just continue using a GET.

Answer 2

Hi,

I would go with the 'refreshes' resource approach. This has two major benefits

(a) Like life-cycle operations (copy, clone, move) the purpose of the refresh is orthogonal to the function of the underlying resource so should be completely separate

(b) It gives you some way of checking the progress of the refresh - the external state of the refresh resource would provide you with a 'status' or 'progress' attribute.

We've implemented the life-cycle operations this way and the separation of concerns is a big design plus.

Chris