[freeipa PR#5207][opened] Use a state to determine if a 389-ds upgrade is in progress

[rcritten]

   URL: https://github.com/freeipa/freeipa/pull/5207
Author: rcritten
 Title: #5207: Use a state to determine if a 389-ds upgrade is in progress
Action: opened

PR body:
"""
When applying update files to 389 the listeners are disabled.
There is a large try/except around this so that if a failure
happens then the configuration should be automatically
restored.

We've seen multiple cases where this doesn't occur. Best guess
is that users are killing or ^C breaking out of the script.

What happens in that case is that when the next upgrade is run
the configuration is backed up again overwriting the original
values. This leaves dirsrv with no listener on 389.

Add a new state, upgrade-in-progress, so that the backup of the
config information can be skipped when the upgrader is executed
again after a failure.

The idea behind using a new state value is that if additional
attributes are ever backed up we don't need to remember to update
the list of possible saved values to check to decide if the
upgrade is in progress.

https://pagure.io/freeipa/issue/7534

Signed-off-by: Rob Crittenden <rcritten(a)redhat.com&gt;

**NOTE**: automated testing is very difficult because getting the timing right would be
nearly impossible. I manually tested in two ways:

* Used the pdb module so that the upgrade stopped in the middle and I killed the upgrade
process
* Spammed the keyboard with ^C in the middle of the DS upgrade process

Look for the last three elements in ```/var/lib/ipa/sysrestore/sysrestore.state```
```
[dirsrv]
serverid = EXAMPLE-TEST
enabled = True
upgrade-in-progress = True
nsslapd-port = 389
nsslapd-security = on
schema_compat_enabled = on
```
If these are left over killing the upgrader then re-running it should debug log that the
values aren't being saved again.
"""

To pull the PR as Git branch:
git remote add ghfreeipa https://github.com/freeipa/freeipa
git fetch ghfreeipa pull/5207/head:pr5207
git checkout pr5207

[freeipa PR#5207][closed] Use a state to determine if a 389-ds upgrade is in progress

[rcritten]

   URL: https://github.com/freeipa/freeipa/pull/5207
Author: rcritten
 Title: #5207: Use a state to determine if a 389-ds upgrade is in progress
Action: closed

To pull the PR as Git branch:
git remote add ghfreeipa https://github.com/freeipa/freeipa
git fetch ghfreeipa pull/5207/head:pr5207
git checkout pr5207