Infinite recursion in StackManager.list's paginate sub-function

[Jason Dunsmore]

If you start 20 "stack-create"s (single- or multi-engine), heatclient hangs due to a recursive call to paginate() inside of StackManager.list. Here's the output:
http://dunsmor.com/heat/multi-engine.html#sec-1-4-1

Here's the command to reproduce:

for i in {1..20}; do heat_client stack-create wp$i -u http://dunsmor.com/heat/heat-templates/rackspace/Wordpress_Single_Instance.yaml -P "DBUsername=wp;DBPassword=verybadpassword" & done

...where heat_client is:

heat_client() {
    heat --heat-url http://1.2.3.4:8004/v1/12345 --os-username myuser --os-password mypass --os-tenant-name 12345 --os-auth-url https://identity.api.rackspacecloud.com/v2.0/ $@
}

At that point, several of the "stack-create" calls will be stuck. A "stack-list" will also get stuck.

[Clint Byrum (clint-fewbar)]

Seems we've had at least two sightings. Marking as Confirmed.

[Steve Baker (steve-stevebaker)]

I have a test which replicates this.

The problem is that the client assumes that the server supports pagination, which currently it does not. Even if we implemented pagination on the server now, this issue would still occur on older server versions.

The fix for the the client will be: if no page size is explicitly specified, perform no pagination.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/40152

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/40152
Committed: http://github.com/openstack/python-heatclient/commit/79dea076dbd5f35c0572b51dfcceeb5112772091
Submitter: Jenkins
Branch: master

commit 79dea076dbd5f35c0572b51dfcceeb5112772091
Author: Steve Baker <email address hidden>
Date: Mon Aug 5 15:29:16 2013 +1200

    Do not paginate stack list unless page_size is set

    Pagination on the server has not yet been implemented, however
    the client assumes it is, causing infinite recursion when paginate
    is called.

    With this change, no pagination is attempted unless page_size is
    specified. However the 'limit' parameter is still honored, so it
    is still possible to cap the total number of results returned.

    heatclient users should not set page_size until pagination has been
    implemented on the server. The stack list in Horizon currently
    does not attempt to paginate, so is not affected.

    Fixes: bug #1207839
    Change-Id: I4087d3a8af48206d6ebe3edc441469464e4a401a