Create new entry for RetroArch Cloud Sync (first version)

docs/guides/retroarch-cloud-sync.md

@@ -0,0 +1,67 @@
+# What is it?
+
+RetroArch Cloud Sync enables a seamless synchronization of the most important system configuration and save data to a dedicated private webdav server, from where these data can be synchronized across Apple devices. The current functionality is limited to Apple devices (MacOS, iOS, tvOS) because it was developed here. It can be deployed to other RetroArch operating systems, if a developer is interested in this work.
+
+RetroArch Cloud Sync currently syncs all data from the following directories:
+
+/"YourUser"/Documents/RetroArch/saves - original system saves
+/"YourUser"/Documents/RetroArch/states - RetroArch save states
+/"YourUser"/Library/Application Support/RetroArch/config - the global retroarch.cfg and all core-specific configurations, core options and shader configurations
+
+"YourUser" refers to your $HOME user in MacOS
+
+## How to configure it
+
+As with any sync solution, it is recommended to start with one device and ensure a proper functioning. Only then a second device should be added.
+
+### Initial configuration with first device
+
+In order to start with Cloud sync, you need an own webdav account that is accessible by MacOS via Connect to Server -> https://webdav.xxxxxx.xxx/.
+
+!!! Tip
+    It is obviously the best way to start with your leading RetroArch system, as this will bring the most important data into the webdav account first. In this account, create an own folder called RetroArch.
+
+Within RetroArch, go to Settings/Saving/Cloud Sync
+    Enable Cloud Sync -> ON
+    Destructive Cloud Sync -> OFF (keeps a backup in a dedicated subfolder called "deleted", and the file names get a time stamp of deletion)
+    Cloud Sync Backend -> webdav
+    Cloud Storage URL -> https://webdav.xxxxxx.xxx/RetroArch/ (here is the RetroArch subfolder that you created before)
+    Username -> your webdav user
+    Password -> your webdav password
+
+Save this configuration and restart Retroarch. After this restart, the initial sync should start immediately (see progress indicator in the bottom left status line of RetroArch). Depending on your amount of sync data, this can take some time. When this is finished, you could do some testing. For example, launch a game and set a new hiscore, then close the game. Let the sync do its job, then look into the webdav accound, and the new hiscore should be there.
+
+### Configuration of a second device
+
+With the second device, so the identical steps in RetroArch as with the first device. From now on, the two devices should be in sync!
+
+!!! Important Note
+    Be very careful that these directory save settings are also identical on all sync devices:
+    - Sort Saves into Folders by Core Name - ON/OFF
+    - Sort Save States into Folders by Core Name - ON/OFF
+    - Sort Saves into Folders by Content Directory - ON/OFF
+    - Sort Save States into Folders by Content Directory - ON/OFF
+    If these settings are not matching, the sync is likely to fail, as the devices store its data in different directories.
+
+## Further details of the solution
+
+### Sync Status
+
+Syncing is displayed in the bottom left status line of RetroArch.
+
+As soon as the solution is properly configured, Cloud Sync starts immediately at launching RetroArch. This is apparently important if other devices synced new data to the webdav repository. They are then immediately picked up.
+
+Another sync is triggered with every closing of a game.
+
+### .DS_Store files create conflicts
+
+RetroArch Cloud Sync may run in sync problems if .DS_Store files are synced into the cloud repository. It is therefore recommended to delete all .DS_Store files from the synced directories.
+
+For example, you can delete the .DS.Store files from the relevant RetroArch directories from the terminal as follows (easiest way is that you create an .sh file containing these lines and make it executable via chmod 755):
+
+cd /"YourUser"/Documents/RetroArch 
+find . -name '.DS_Store' -type f -delete
+cd /"YourUser"/Library/Application\ Support/RetroArch
+find . -name '.DS_Store' -type f -delete
+
+After deletion, the sync also deletes these .DS_Store files from the cloud repository.

mkdocs.yml

@@ -71,6 +71,7 @@ nav:
       - 'Video Recording and Streaming': 'guides/recording-and-streaming.md'
       - 'Troubleshooting': 'guides/troubleshooting-retroarch.md'
       - 'Generating Logs': 'guides/generating-retroarch-logs.md'
+      - 'RetroArch Cloud Sync (Apple Devices)': 'guides/retroarch-cloud-sync.md'
     - 'Appearance & Customization':
       - 'Creating a Theme': 'guides/themes.md'
       - 'Playlists and Thumbnails': 'guides/roms-playlists-thumbnails.md'