Datastore clear() async implementation #353
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| @@ -82,13 +84,15 @@ extension AWSDataStorePlugin: DataStoreBaseBehavior { | |||
| public func delete<M: Model>(_ modelType: M.Type, | |||
| withId id: String, | |||
| completion: @escaping DataStoreCallback<Void>) { | |||
| reinitStorageEngineIfNeeded() | |||
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Instead of doing it lazy-init-style here, can you do it eagerly, right before your completion(.successfulVoid) calls inside of clear(...)?
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Hmm! I would have liked to do what you suggested.. hmmm but...
Based on the implementation of reinitStorageEngineIfNeeded(), I don't think this is what we want, because then we would be calling storage.startSync() which would attempt to restart the entire SyncEngine (so... then we'd potentially rehydrate the data base we just deleted)
If reinitStorageEngine were to be changed to only resolveTheStorageEngine (and not start the sync engine), we'd still have to call to startSyncEngine on any query/delete/subscription. At this point, i'm not seeing a huge benefit one way or the other.
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| } | ||
| self.dataStorePublisher = nil | ||
|
|
||
| if let error = sError { |
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Why not just invoke completion(result)? You should then be able to get rid of L141-147 as well
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WHOA! How did i not see that?! Thank you!
updated to:
self.storageEngine = nil
if #available(iOS 13.0, *) {
if let publisher = self.dataStorePublisher as? DataStorePublisher {
publisher.sendFinished()
}
}
self.dataStorePublisher = nil
completion(result)
| completion(.failure(causedBy: DataStoreError.invalidDatabase(path: "Database path not set", nil))) | ||
| return | ||
| } | ||
| connection = nil |
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I don't remember the SQLite API, but is there a cancel or teardown that we should invoke before releasing our connection?
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I looked in the following link, but didn't see anything:
https://github.com/stephencelis/SQLite.swift/blob/master/Documentation/Index.md
Hmm but, the way I arrived at this approach (connection = nil) is that i noticed that we needed to a call to sqlite3_close() -- which seems to be in the deinit of the Connection class. So I figured this was how to 'teardown' the connection.
I'm going to leave this as-is for now.
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wooj2
changed the title
. clear() is an async interface
. After calling clear() on DataStore, the datastore is in an idle state -- that is, the remote sync engine has stopped, all subscriptions have been severed and any publishers the customer may have been listening were called with receiveCompletion() (meaning, they will need to re-subscribe)
. Any subsequent call to query, save, delete, publisher() will restart the sync engine and publishers, mirroring JS's behavior
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