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OpenStack Horizon good catch

Wanna share my joy, i always want to finish _debugging_ with awesome oneline fix…this is it.

We’r doing multi-regional OpenStack across at least 7 datacenters. PKI tokens are really good for such kind of deployments.

– No token storage required. (except non-critical token hashes)
– Token verification without keystone

Unfortunately cons of this approach that token are pretty big ~8Kbytes. At least full catalog packed into token. Finally we’r using PKIZ (compressed PKI) to decrease the size (Backported to Icehouse from Juno).

All works like a charm…before today after adding one more region. We’ve noticed that Horizon stopped to show “Project” tab nor any additional tenants for user. From CLI all works perfectly.

Error:  Request attribute token must be less than or equal to 8192.

Finally found that we’r affected by this bug. Horizon while getting project list tries to send _full_ token instead of id (md5 hash) that’s why token not fits into 8K.

The simplest workaround (not the solution) was to increase keystone “max_token_size”. My challenge was to not finish on this easy workaround and continue to dig deeper.

P.S.: My uncompressed token was 8.5K (88 endpoints)
P.S.S.: Large OpenStack community has it’s benefits: in 80% cases someone already plunged into your issue and filled a bug .