Querying imported files and folders on iOS using NSMetadataQuery

Hi all,

I’m trying to use NSMetadataQuery on iOS to track changes to folders users have imported from elsewhere but, no matter what I try, I get no results.

Following the documentation for searching file metadata with NSMetadataQuery, I’m creating a live query (albeit in Swift) and listening for […]QueryDidFinishGathering and […]QueryDidUpdate. The former fires, with no results, and the latter never fires.

I’ve also tried following the Synchronizing Documents in the iCloud Environment example, adding the appropriate Ubiquity keys to my Info.plist and .entitlements file, with no change.

I’m importing files and folders using SwiftUI’s View.fileImporter(isPresented:allowedContentTypes:allowsMultipleSelection:onCompletion:), but can’t see how I might security-scope the NSMetadataQuery’s execution (if that’s even a thing?).

My test project is on GitHub, but the main parts are below…

My query method:

extension NSMetadataQueryUbiquitousExternalDocumentsTestApp {
    func findAccessibleFiles() {
        query.stop()
        fileMonitor?.cancel()


        fileMonitor = Publishers.MergeMany(
            [
                .NSMetadataQueryDidFinishGathering,
                .NSMetadataQueryDidUpdate
            ].map { NotificationCenter.default.publisher(for: $0) }
        )
            .receive(on: DispatchQueue.main)
            .sink { notification in
                query.disableUpdates()
                defer { query.enableUpdates() }


                foundItems = query.results as! [NSMetadataItem]
                print("Query posted \(notification.name.rawValue) with results: \(query.results)")
            }


        query.searchScopes = [
            NSMetadataQueryAccessibleUbiquitousExternalDocumentsScope
        ]
        query.predicate = NSPredicate(
            format: "%K LIKE %@",
            argumentArray: [NSMetadataItemFSNameKey, "*"]
        )
        query.sortDescriptors = [
            NSSortDescriptor(key: NSMetadataItemFSNameKey, ascending: true)
        ]


        if query.start() {
            print("Query started")
        } else {
            print("Query didn't start for some reason")
        }
    }
}

Info.plist:

[…]
<key>NSUbiquitousContainers</key>
  <dict>
    <key>iCloud.com.stevemarshall.AnnotateML</key>
		<dict>
			<key>NSUbiquitousContainerIsDocumentScopePublic</key>
			<true/>
			<key>NSUbiquitousContainerName</key>
			<string>AnnotateML</string>
			<key>NSUbiquitousContainerSupportedFolderLevels</key>
			<string>ANY</string>
		</dict>
	</dict>
[…]