jclouds does not re-auth on Swift early-token-expiry

I create a blobstore against swift in the usual way. It works for a while but then (after many hours) it starts to return 401 Unauthorized (again for many hours) and then it works again.

It appears:

• Jclouds does not re-negotiate the token immediately if it is expired server-side, but it does on cache expiry (from my observations)
• Swift can sometimes expire tokens earlier than their advertised expiration date (according to [1])

Desired behaviour: I think jclouds should attempt to re-negotiate the auth token if it gets an unauthorized exception using apparently-valid credentials.

I've observed this against Softlayer [2]. I have also seen this reported against HP [1].

We are looking at a workaround which retries in user space, also referenced at [2], but fixing this in jclouds would be great.

I also note the cache expiry time is hard-coded at 23 hours. All the swifts I have seen claim 24h expiry time so this is okay most of the time, but it is a hack and not guaranteed. The REST response includes the expiry time explicitly so a related improvement I notice would be to use this (minus 1m or so...) when setting the cache value. (But the token can still expire sooner than this advertised expiry time – IOW the main bug reported here is independent of this cache expiry time issue.)

[1] https://community.hpcloud.com/question/1477/about-authentication-token-expiration-when-using-jclouds-api-access-hpcs-object
[2] https://issues.apache.org/jira/browse/BROOKLYN-6