Fixing #9 and #8

Sources/Server/Controllers/UserController/UserController.swift

@@ -222,14 +222,27 @@ class UserController : ControllerProtocol {
             return
         }
 
-        // When deleting a user, should set to NULL any sharing users that have that userId (being deleted) as their owningUserId.
+        // TODO: When deleting a user, should set to NULL any sharing users that have that userId (being deleted) as their owningUserId.
 
+        // This is somewhat aggressive: I'm going to remove both `Upload` and `DeferredUpload` records. It's somewhat aggressive because this gets rid of "work" the user has already done. However both of these record types have a UserId field, and this userId is being removed below (when we remove the `UserRepository` record). Plus, if the user was the cloud storage owner on these files, these files are getting marked as deleted as part of this user deletion anyways.
         let uploadRepoKey = UploadRepository.LookupKey.userId(params.currentSignedInUser!.userId)
         let removeResult2 = params.repos.upload.retry {
             return params.repos.upload.remove(key: uploadRepoKey)
         }
         guard case .removed = removeResult2 else {
-            let message = "Could not remove upload files for user!"
+            let message = "Could not remove Upload records for user!"
+            Log.error(message)
+            params.completion(.failure(.message(message)))
+            return
+        }
+
+        // 11/28/20; Didn't have this DeferredUpload deletion until today. I think this was the source of https://github.com/SyncServerII/ServerMain/issues/9 and https://github.com/SyncServerII/ServerMain/issues/8.
+        let deferrredUploadRepoKey = DeferredUploadRepository.LookupKey.userId(params.currentSignedInUser!.userId)
+        let deferrredUploadRemoveResult = params.repos.deferredUpload.retry {
+            return params.repos.deferredUpload.remove(key: deferrredUploadRepoKey)
+        }
+        guard case .removed = deferrredUploadRemoveResult else {
+            let message = "Could not remove DeferredUpload records for user!"
             Log.error(message)
             params.completion(.failure(.message(message)))
             return

Sources/Server/Database/Files/DeferredUploadRepository.swift

@@ -141,6 +141,7 @@ class DeferredUploadRepository : Repository, RepositoryLookup, ModelIndexId {
         case deferredUploadId(Int64)
         case fileGroupUUIDWithStatus(fileGroupUUID: String, status: DeferredUploadStatus)
         case resultsUUID(String)
+        case userId(UserId)
 
         var description : String {
             switch self {
@@ -150,6 +151,8 @@ class DeferredUploadRepository : Repository, RepositoryLookup, ModelIndexId {
                 return "fileGroupUUID(\(fileGroupUUID); status: \(status.rawValue))"
             case .resultsUUID(let resultsUUID):
                 return "resultsUUID(\(resultsUUID))"
+            case .userId(let userId):
+                return "userId(\(userId))"
             }
         }
     }
@@ -162,6 +165,8 @@ class DeferredUploadRepository : Repository, RepositoryLookup, ModelIndexId {
             return "fileGroupUUID = '\(fileGroupUUID)' and status = '\(status.rawValue)'"
         case .resultsUUID(let resultsUUID):
             return "resultsUUID = '\(resultsUUID)'"
+        case .userId(let userId):
+            return "userId = \(userId)"
         }
     }
 
@@ -244,6 +249,7 @@ class DeferredUploadRepository : Repository, RepositoryLookup, ModelIndexId {
     }
 
     // A nil result indicates an error. No rows in the query is returned as an empty array.
+    // This `select` is not constrained by `UserId` because it is used from the `Uploader`, and the intent there is that the Uploader works *across* users.
     func select(rowsWithStatus status: [DeferredUploadStatus]) -> [DeferredUpload]? {
         let quotedStatusString = status.map {$0.rawValue}.map {"'\($0)'"}.joined(separator: ",")
 

Sources/Server/ServerUploader/Uploader+UploadDeletion.swift

@@ -79,6 +79,7 @@ extension Uploader {
             throw Errors.mismatchWithDeferredUploadIdsCount
         }
 
+        // Case 2) continued
         if deferredUploadIds.count > 0 {
             guard let theUploads = uploadRepo.select(forDeferredUploadIds: deferredUploadIds) else {
                 throw Errors.failedToGetUploads
@@ -104,12 +105,14 @@ extension Uploader {
             }
         }
 
+        // End: specific code for Case 1) and Case 2); moving on to more general code.
+
         // Not going to worry about any resulting errors because: (a) we might be trying the deletion a 2nd (or more) time and the file might just not be there, (b) the consequences of leaving a file in cloud storage are not dire-- just some garbage that could possibly be cleaned up later.
         if let errors = FileDeletion.apply(deletions: fileDeletions) {
             Log.warning("Some error(s) occurred while deleting files: \(errors)")
         }
 
-        // Now, delete the database records.
+        // Now, delete the Upload database records, and change the status of the DeferredUpload records to `completed`.
 
         for upload in uploads {
             let key = UploadRepository.LookupKey.uploadId(upload.uploadId)

Sources/Server/ServerUploader/Uploader.swift

@@ -142,7 +142,8 @@ class Uploader: UploaderProtocol {
         }
 
         Log.debug("Got lock!")
-
+
+        // Get `pendingDeletions` across all users. The `Uploader` works across all users-- and this is OK because of the mutex lock.
         guard let deferredFileDeletions = deferredUploadRepo.select(rowsWithStatus: [.pendingDeletion]) else {
             Log.error("Failed setting up select to get deferred upload deletions")
             try releaseLock()
@@ -152,6 +153,7 @@ class Uploader: UploaderProtocol {
         // Must do pruning based on deletions before fetching the deferred file changes. Because the pruning may remove some of the deferred file changes.
         guard pruneFileUploads(deferredFileDeletions: deferredFileDeletions) else {
             Log.error("Failed pruning file uploads.")
+            // TODO(https://github.com/SyncServerII/ServerMain/issues/9)
             try releaseLock()
             throw Errors.failedToGetDeferredUploads
         }
@@ -351,6 +353,7 @@ class Uploader: UploaderProtocol {
     }
 
     // Remove file uploads (DeferredUpload, Upload's) corresponding to these deletions. They are not relevant any more given that we're doing deletions.
+    // If `deferredFileDeletions` is empty, this returns immediately.
     func pruneFileUploads(deferredFileDeletions: [DeferredUpload]) -> Bool {
         guard deferredFileDeletions.count > 0 else {
             return true
@@ -396,8 +399,7 @@ class Uploader: UploaderProtocol {
             var deferredIdsForFileChangeUploads = [Int64]()
 
             for deferredDeletion in deferredDeletionsWithoutFileGroups {
-                #warning("9/20/20: This lookup just failed. And the server is now stuck in terms of deferred operations. Need some means of removing these if they fail more than a set number of times. This looks like an example where I could record this on the deferred upload record as an error-- so the client can know of the failure.")
-                #warning("If we get this again, one fix would be to remove the DeferredUpload that caused this to fail.")
+                // TODO(https://github.com/SyncServerII/ServerMain/issues/8)
                 // Get the deletion Upload associated with this `deferredDeletion`
                 let key1 = UploadRepository.LookupKey.deferredUploadId(deferredDeletion.deferredUploadId)
                 guard case .found(let model) = uploadRepo.lookup(key: key1, modelInit: Upload.init), let uploadDeletion = model as? Upload else {
@@ -427,7 +429,7 @@ class Uploader: UploaderProtocol {
                         return false
                     }
                 }
-            } // end for
+            } // end for: deferredDeletionsWithoutFileGroups
 
             // Get rid of any non-distinct deferredUploadId's for file DeferredUpload's
             deferredIdsForFileChangeUploads = Array(Set<Int64>(deferredIdsForFileChangeUploads))