Doc: Added idea: Multi-profile support, for GSoC

Tools/build-website.js

@@ -588,6 +588,7 @@ async function main() {
 		[ 'readme/gsoc/idea_search.md', 'docs/gsoc/idea_search.html', { title: 'GSoC: Idea: Search' } ],
 		[ 'readme/gsoc/idea_mobile_sharing.md', 'docs/gsoc/idea_mobile_sharing.html', { title: 'GSoC: Idea: Mobile Sharing' } ],
 		[ 'readme/gsoc/idea_ocr.md', 'docs/gsoc/idea_ocr.html', { title: 'GSoC: Idea: OCR Support' } ],
+		[ 'readme/gsoc/idea_multi_profiles.md', 'docs/gsoc/idea_multi_profiles.html', { title: 'GSoC: Idea: Multi-Profile Support' } ],
 	];
 
 	const path = require('path');

readme/gsoc/idea_multi_profiles.md

@@ -0,0 +1,81 @@
+# GSoC: Support for multiple profiles
+
+The applications should support multiple profiles so that, for example, one can have a "work" profile and "personal" profile. This will also make it easier to share notes because for example a "work project" profile could be created and share with co-workers.
+
+## Specification
+
+Provide a way to switch profiles from the app:
+
+- The user clicks on a menu and select change profile
+- The list of available profiles is displayed
+- User selects on of the profile
+- The app closes and re-open and load the selected profile
+
+### Changing the structure of the profile directory
+
+The structure of the profile directory needs to be changed for this to work.
+
+Currently, the profile is organised like this:
+
+* ~/.config/joplin-desktop/
+	* resources/
+	* database.sqlite
+
+If we want to support multiple profiles, the config directory should be changed like so (in a way similar to Firefox or Thunderbird multi-profile support):
+
+* ~/.config/joplin-desktop/
+	* PROFILE_ID_1/
+	* PROFILE_ID_2/
+	* etc.
+	* profile.ini
+
+The PROFILE_ID_x directories will be named with a UUID and contain the same profile as above with the "resources" and "database.sqlite" file.
+
+`profile.ini` will tell what profiles are available. It's content will be like this (same as Firefox):
+
+```ini
+[Profile1]
+Name=Personal
+IsRelative=1
+Path=cdb4ar19.Personal
+
+[Profile0]
+Name=default
+IsRelative=1
+Path=Profiles/ts6eud8o.default
+Default=1
+
+[Profile2]
+Name=Work
+IsRelative=1
+Path=Profiles/ts9akd8o.work
+
+[General]
+StartWithLastProfile=1
+Version=1
+```
+
+Since the profile directory is changed, there should be a migration step that will convert old profiles to the new structure when the app starts.
+
+### Switching profiles
+
+To switch profile, save a value to the Settings called "next_profile_id", then close and restart the app. When the app starts it loads "profile.ini", then checks the value of "next_profile_id", and uses that to choose and load the right profile.
+
+### Locking per profile
+
+Each app needs to make sure that a given profile can only be open by one application, so there should be form of lock. If a profile is locked, it means it's already opened by another application, so the current application should close.
+
+Locking should be implemented in such a way that if an app crashes, the lock is released. So probably some form of in-memory lock.
+
+### Desktop implementation
+
+To restart the app use the built-in Electron function: https://electronjs.org/docs/api/app#apprelaunchoptions
+
+### Mobile implementation
+
+On mobile, give a try to this package to restart the app: https://www.npmjs.com/package/react-native-restart
+
+## See also
+
+- Forum thread: https://discourse.joplinapp.org/t/can-i-run-a-second-instance-of-joplin/110
+- GitHub issue: https://github.com/laurent22/joplin/issues/591

readme/gsoc/index.md

@@ -158,3 +158,4 @@ Finally, know that we will never assign you to a project you do not want to work
 - [Idea: Search](https://joplinapp.org/gsoc/idea_search.html)
 - [Idea: Mobile Sharing](https://joplinapp.org/gsoc/idea_mobile_sharing.html)
 - [Idea: OCR Support](https://joplinapp.org/gsoc/idea_ocr.html)
+- [Idea: Multi-profile support](https://joplinapp.org/gsoc/idea_multi_profiles.html)