Subscriptions are added back again by migration

When removing a subscription, it's only removed from the database. When the synchronization runs, the worker sees the calendar on the system, but not the entry in the database, and it considers it as "an old calendar", and migrates it.

This is even worse, since in the conversion from subscription to calendar properties, we don't add NAME:

icsx5/app/src/main/java/at/bitfire/icsdroid/db/entity/Subscription.kt

Lines 75 to 85 in 34ab68d

    
               /** 
        
                * Converts this subscription's properties to [android.content.ContentValues] that can be 
        
                * passed to the calendar provider in order to create/update the local calendar. 
        
                */ 
        
               fun toCalendarProperties() = contentValuesOf( 
        
                   Calendars._ID to id, 
        
                   Calendars.CALENDAR_DISPLAY_NAME to displayName, 
        
                   Calendars.CALENDAR_COLOR to color, 
        
                   Calendars.CALENDAR_ACCESS_LEVEL to Calendars.CAL_ACCESS_READ, 
        
                   Calendars.SYNC_EVENTS to 1 
        
               )

So the system doesn't know the url of the subscription, and just adds them with https://invalid-url as specified here:

icsx5/app/src/main/java/at/bitfire/icsdroid/db/entity/Subscription.kt

Lines 61 to 63 in 34ab68d

    
           id = calendar.id, 
        
           url = Uri.parse(calendar.url ?: "https://invalid-url"), 
        
           eTag = calendar.eTag,

We should fix the Subscription -> ContentValues conversion with this:

    /**
     * Converts this subscription's properties to [android.content.ContentValues] that can be
     * passed to the calendar provider in order to create/update the local calendar.
     */
    fun toCalendarProperties() = contentValuesOf(
        Calendars._ID to id,
        Calendars.NAME to url.toString(),
        Calendars.CALENDAR_DISPLAY_NAME to displayName,
        Calendars.CALENDAR_COLOR to color,
        Calendars.CALENDAR_ACCESS_LEVEL to Calendars.CAL_ACCESS_READ,
        Calendars.SYNC_EVENTS to 1
    )

Which is fixed here: 3a84525

For migration, I suggest simply removing this process from synchronization, and moving it to the callback on the database creation:

icsx5/app/src/main/java/at/bitfire/icsdroid/db/AppDatabase.kt

Lines 61 to 66 in 34ab68d

    
           .addCallback(object : Callback() { 
        
               override fun onCreate(db: SupportSQLiteDatabase) { 
        
                   super.onCreate(db) 
        
                   SyncWorker.run(context, onlyMigrate = true) 
        
               } 
        
           })

Since I think there are really no reasons to run migration again after the database has been created. This also gets rid of ONLY_MIGRATE from the worker, which is a bit specific.

Depends on #133

This PR/issue depends on: * ~~#133~~

Fixed by 606960e

	/**
	* Converts this subscription's properties to [android.content.ContentValues] that can be
	* passed to the calendar provider in order to create/update the local calendar.
	*/
	fun toCalendarProperties() = contentValuesOf(
	Calendars._ID to id,
	Calendars.CALENDAR_DISPLAY_NAME to displayName,
	Calendars.CALENDAR_COLOR to color,
	Calendars.CALENDAR_ACCESS_LEVEL to Calendars.CAL_ACCESS_READ,
	Calendars.SYNC_EVENTS to 1
	)

	id = calendar.id,
	url = Uri.parse(calendar.url ?: "https://invalid-url"),
	eTag = calendar.eTag,

	.addCallback(object : Callback() {
	override fun onCreate(db: SupportSQLiteDatabase) {
	super.onCreate(db)
	SyncWorker.run(context, onlyMigrate = true)
	}
	})