Built a tool to upgrade old Factorio game save files to the newest version, using factoriotools/factorio

[joelpurra]

Soooo, during the weekend I thought of continuing playing this one amazing (not really) map I worked on a couple of years ago. Already knew that the save file was outdated and could not be loaded in Factorio 1.1. While I only wanted to upgrade a single save file, I ended up hacking together a small tool for it. (Please don't tell me there's a well-known tool which already does this...)

https://github.com/joelpurra/factorio-save-upgrader

It's basically a single Bash script; Linux support only. Much more convenient than manual steps, including simply switching versions in Steam, for batch upgrading everything in (for example) ~/.factorio/saves/

Here's the concept:

Loading
1.1   1.0   0.18   0.17   0.16
❌ --> ❌ --> ❌ --> ✅ ... ❓ ...
                    |
Upgrading           |
1.1   1.0   0.18    |
✅ <-- ✅ <-- ✅ <----

Sample log output

2022-07-11T18:14:42+02:00 factorio-save-upgrader INFO: Upgrading save file: '/home/user/.factorio/saves/map.zip'
2022-07-11T18:14:42+02:00 factorio-save-upgrader INFO: Attempting to load save in Factorio docker image 'factoriotools/factorio:1.1' (timeout 10s)
2022-07-11T18:14:44+02:00 factorio-save-upgrader INFO: Failed when using 'factoriotools/factorio:1.1'
2022-07-11T18:14:44+02:00 factorio-save-upgrader INFO: Attempting to load save in Factorio docker image 'factoriotools/factorio:1.0' (timeout 10s)
2022-07-11T18:14:46+02:00 factorio-save-upgrader INFO: Failed when using 'factoriotools/factorio:1.0'
2022-07-11T18:14:46+02:00 factorio-save-upgrader INFO: Attempting to load save in Factorio docker image 'factoriotools/factorio:0.18' (timeout 10s)
2022-07-11T18:14:48+02:00 factorio-save-upgrader INFO: Failed when using 'factoriotools/factorio:0.18'
2022-07-11T18:14:49+02:00 factorio-save-upgrader INFO: Attempting to load save in Factorio docker image 'factoriotools/factorio:0.17' (timeout 10s)
2022-07-11T18:15:00+02:00 factorio-save-upgrader INFO: Succeeded when using 'factoriotools/factorio:0.17'
2022-07-11T18:15:00+02:00 factorio-save-upgrader INFO: Attempting to load save in Factorio docker image 'factoriotools/factorio:0.18' (timeout 10s)
2022-07-11T18:15:11+02:00 factorio-save-upgrader INFO: Succeeded when using 'factoriotools/factorio:0.18'
2022-07-11T18:15:12+02:00 factorio-save-upgrader INFO: Attempting to load save in Factorio docker image 'factoriotools/factorio:1.0' (timeout 10s)
2022-07-11T18:15:23+02:00 factorio-save-upgrader INFO: Succeeded when using 'factoriotools/factorio:1.0'
2022-07-11T18:15:23+02:00 factorio-save-upgrader INFO: Attempting to load save in Factorio docker image 'factoriotools/factorio:1.1' (timeout 10s)
2022-07-11T18:15:34+02:00 factorio-save-upgrader INFO: Succeeded when using 'factoriotools/factorio:1.1'
2022-07-11T18:15:35+02:00 factorio-save-upgrader INFO: Loaded the save file in version 0.17, then upgraded it to version 1.1: '/home/user/saves-upgraded/map.zip'

The tool uses the factoriotools/factorio images and iterates over the major Factorio versions by tag. First it loads (a copy of) the save in the most recent version possible, then upgrades it stepwise to the most recent version available. After shutting down the last instance the map is fully upgraded, and the modified file is put in the output directory.

Seems to work well enough, at least for medium-sized maps down to 0.16. Only tested on a tiny map for 0.15, and nothing older. There are crashes in entrypoint.sh in some older versions (#430) but looks fixable. Who can confirm if 0.15 (or older) works for complex maps?

Thanks for dockerizing Factorio, it is very useful!