Event histories after merging serve as an authorotative list of
events that can be seen as ones persisted by etcd, we don't need
PrevValue as part of it.
Signed-off-by: Madhav Jivrajani <madhav.jiv@gmail.com>
Kubernetes relies on the PrevKV() option in the watches it opens
against etcd. This commit adds a robustness test to validate the
same.
A watch response returned with PrevKV() is valid if:
The value in current event's prevKV matches the previous
event's value of the same key if this is not a create event.
There are cases where there can be a prevKV for a create event
as well, for example if a watch is opened after the key is creatd.
Since we don't simulate for that, we don't check for that.
Further, this adjusts revision numbers such that we can successfully create
a new replay. Needed now since we will have unit tests with
and without PrevKV co-existing and we requite creation of a
new replay everytime we validate PrevKV.
We also regenerate test data with so that prevKV exists in it
Signed-off-by: Madhav Jivrajani <madhav.jiv@gmail.com>
Creation of event history requires each client to return consistent
events. If clients observed inconsistent view of some revision, merging
will fail and return diff between two clients. This however doesn't
provide hint on what kind of issue happend.
This PR helps cases where there is an error with single watch
stream (like event duplication) by running normal watch validation even
without full event history.
Signed-off-by: Marek Siarkowicz <siarkowicz@google.com>
For now we just validate stale read revision, but not response content.
Reason is that etcd model only stores latest version of keys, and no
history like real etcd.
Validating stale read contents needs to be done outside of model
as storing whole history is just to costly for linearization validation.
Signed-off-by: Marek Siarkowicz <siarkowicz@google.com>
