EZP-30823: Fixed possible race condition on version loading

[andrerom]

Question	Answer
JIRA issue	EZP-30823
Bug/Improvement	yes
Target version	6.7
BC breaks	no
Tests pass	yes
Doc needed	no

Change version loading to not rely on first having to load content info to get current version number (risking it having changed in between), just like done for content load some time ago.

BENEFIT: Avoids having to load ContentInfo within loadVersionInfo() when loading current version.

TODO:

• Implement feature / fix a bug.
• Implement tests.
• Fix new code according to Coding Standards ($ composer fix-cs).
• Ask for Code Review.

ON MERGE:

• Update SQL for version load to also add new columns: (ezcontentobject_is_hidden, ...), patch:

diff --git a/eZ/Publish/Core/Persistence/Legacy/Content/Gateway/DoctrineDatabase/QueryBuilder.php b/eZ/Publish/Core/Persistence/Legacy/Content/Gateway/DoctrineDatabase/QueryBuilder.php
index 920785536b..09f6b7b1f3 100644
--- a/eZ/Publish/Core/Persistence/Legacy/Content/Gateway/DoctrineDatabase/QueryBuilder.php
+++ b/eZ/Publish/Core/Persistence/Legacy/Content/Gateway/DoctrineDatabase/QueryBuilder.php
@@ -279,6 +279,7 @@ class QueryBuilder
                 'c.status AS ezcontentobject_status',
                 'c.name AS ezcontentobject_name',
                 'c.language_mask AS ezcontentobject_language_mask',
+                'c.is_hidden AS ezcontentobject_is_hidden',
                 'v.id AS ezcontentobject_version_id',
                 'v.version AS ezcontentobject_version_version',
                 'v.modified AS ezcontentobject_version_modified',

[andrerom]

@ezsystems/qa-team : This one is ready for testing, but the two others on cache transaction isolation (#2740, #2749) are still waiting for review. Two options:

• Help bug Engineering to review so you can test 😄
• Ask me to split the bug into 2, one on load issue and another on publish/updates (aka transactions) issue

[micszo]

From my pov the most effective way to test both issues would be to have branches for testing with the combined changes for each stable branch. Is that feasible?

[andrerom]

From my pov the most effective way to test both issues would be to have branches for testing with the combined changes for each stable branch. Is that feasible?

yes it is, I'll ping on slack qa channel when I have pushed it

[micszo]

QA Approved.
Retest successful for Content List block issue and wrong current version issue on eZ Platform EE v1.7.9 with 6.7_race_cond_testing branch. Verified with sanities.
As agreed testing on v1.13.5 will be done post merge.
Testing on v2.5 is ongoing in scope of #2749 / 7.5_race_cond_testing branch.