Although Plone 5 has been released for 2 years, there are still lots of Plone 4.3 sites in the wild. A number of Jazkarta's clients have large, heavily customized Plone 4.3 sites and we have been upgrading them one at a time. As we have gained experience, we have developed strategies for these upgrade projects that minimize risk and spread the work over several mini-projects. In this short talk I will share what we have learned.

1. Plone 5 Upgrades
In Real Life
Sally Kleinfeldt, Jazkarta

2. Plone 4.3 is getting old...

3. Python 2.7 EOL in 2020

4. 4.3 => 5 is non-trivial...

5. ...so divide and conquer!

6. 3 separate projects can be
done in any order

7. 1) Upgrade to Plone 5
- Upgrade theme to Diazo
- Upgrade non-compatible add-ons

8. 2) Migrate core content
types AT->DX

9. 3) Migrate custom content
types AT->DX
- Can be done one at a time in mini projects

10. For each custom type
- Create DX type
- Create DX view
- Create migration

11. When all 3 projects done,
upgrade to Python 3!

12. About migrating large
amounts of content...

13. In-Place Migration
Inspired by Alessandro Pisa
https://2017.ploneconf.org/talks/really-unconventional-migrations

14. Custom migrator class for
each type
Shared base class

15. For each type's migrator define lists of:
- attributes to keep/remove
- attributes to move
- interfaces to remove
- annotations to keep/remove
- etc.

16. Base class
- Checks for forgotten attributes and annotations
- Patches catalog to avoid accidentally indexing
while migrating

17. Can share Github gist if
there is interest