Track the list of deleted contracts so we don't refresh contract data for them upon launch

AlphaWallet.xcodeproj/project.pbxproj

@@ -303,6 +303,7 @@
 		5E7C7376B566E5A59CC8F463 /* ImportTicketViewControllerViewModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5E7C72D0E7CA03ADE5CFAE7A /* ImportTicketViewControllerViewModel.swift */; };
 		5E7C73FC3990D110C474C3D6 /* WalletFilterViewModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5E7C75CC640BAFFE0E789F44 /* WalletFilterViewModel.swift */; };
 		5E7C73FD5BD75D90C8D0EF3C /* WalletFilterView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5E7C7C58586099F082973073 /* WalletFilterView.swift */; };
+		5E7C741353DDF87133054FCC /* DeletedContract.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5E7C72BEB789700C49FF64A6 /* DeletedContract.swift */; };
 		5E7C745A423BD10CFDED9A81 /* ServersViewModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5E7C7CBEBF984CFCA29D6866 /* ServersViewModel.swift */; };
 		5E7C745C725F3F34037DCC68 /* SetTransferTicketsExpiryDateViewControllerViewModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5E7C754C0E2E57F32A61F9A3 /* SetTransferTicketsExpiryDateViewControllerViewModel.swift */; };
 		5E7C745DACB5FCCEBCEB49CA /* WelcomeViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5E7C793E23E2364B73C4D813 /* WelcomeViewController.swift */; };
@@ -809,6 +810,7 @@
 		5E7C71EBD4C95AD4E11F3352 /* AlphaWalletSettingsButtonRow.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; name = AlphaWalletSettingsButtonRow.swift; path = Views/AlphaWalletSettingsButtonRow.swift; sourceTree = "<group>"; };
 		5E7C72142D5817EF8FA8CADA /* PrivacyPolicyViewController.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = PrivacyPolicyViewController.swift; sourceTree = "<group>"; };
 		5E7C727433F7B8E322B3C68A /* SetTransferTicketsExpiryDateViewController.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = SetTransferTicketsExpiryDateViewController.swift; sourceTree = "<group>"; };
+		5E7C72BEB789700C49FF64A6 /* DeletedContract.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = DeletedContract.swift; sourceTree = "<group>"; };
 		5E7C72D0E7CA03ADE5CFAE7A /* ImportTicketViewControllerViewModel.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = ImportTicketViewControllerViewModel.swift; sourceTree = "<group>"; };
 		5E7C731B6F01534683227123 /* TicketTokenViewCellViewModel.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = TicketTokenViewCellViewModel.swift; sourceTree = "<group>"; };
 		5E7C73495E0C0A207152EC25 /* LockEnterPasscodeViewController.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; name = LockEnterPasscodeViewController.swift; path = AlphaWallet/AlphaWalletLock/ViewControllers/LockEnterPasscodeViewController.swift; sourceTree = SOURCE_ROOT; };
@@ -1708,6 +1710,7 @@
 				442FC90F0768C43EF903465B /* Ticket.swift */,
 				442FCFEB2D7443C4E0B889B0 /* TicketHolder.swift */,
 				5E7C74B9EB81C51E956566E7 /* TokensDataStore.swift */,
+				5E7C72BEB789700C49FF64A6 /* DeletedContract.swift */,
 			);
 			path = Types;
 			sourceTree = "<group>";
@@ -3645,6 +3648,7 @@
 				5E7C74BD08801CABF9695853 /* LocaleViewModel.swift in Sources */,
 				5E7C7B348A4DB36FC2D39DDF /* AssetField.swift in Sources */,
 				76F1D74912F5D8CDA72363BD /* GetContractInteractions.swift in Sources */,
+				5E7C741353DDF87133054FCC /* DeletedContract.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};

AlphaWallet/Core/Initializers/MirgrationInitializer.swift

@@ -20,7 +20,7 @@ class MigrationInitializer: Initializer {
     }
 
     func perform() {
-        config.schemaVersion = 41
+        config.schemaVersion = 42
         config.migrationBlock = { migration, oldSchemaVersion in
             switch oldSchemaVersion {
             case 0...32:

AlphaWallet/Tokens/Coordinators/TokensCoordinator.swift

@@ -3,6 +3,7 @@
 import Foundation
 import UIKit
 import TrustKeystore
+import Alamofire
 
 protocol TokensCoordinatorDelegate: class {
     func didPress(for type: PaymentFlow, in coordinator: TokensCoordinator)
@@ -17,6 +18,7 @@ private enum ContractData {
     case decimals(UInt8)
     case stormBirdComplete(name: String, symbol: String, balance: [String])
     case nonStormBirdComplete(name: String, symbol: String, decimals: UInt8)
+    case failed(networkReachable: Bool?)
 }
 
 class TokensCoordinator: Coordinator {
@@ -79,7 +81,8 @@ class TokensCoordinator: Coordinator {
         GetContractInteractions(web3: web3).getContractList(address: address.eip55String, chainId: config.chainID) { contracts in
             let detectedContracts = contracts.map { $0.lowercased() }
             let alreadyAddedContracts = self.storage.enabledObject.map { $0.address.eip55String.lowercased() }
-            let contractsToAdd = detectedContracts - alreadyAddedContracts
+            let deletedContracts = self.storage.deletedContracts.map { $0.contract.lowercased() }
+            let contractsToAdd = detectedContracts - alreadyAddedContracts - deletedContracts
             for eachContract in contractsToAdd {
                 self.addToken(for: eachContract)
             }
@@ -114,6 +117,10 @@ class TokensCoordinator: Coordinator {
                 )
                 self.storage.add(tokens: [token])
                 self.tokensViewController.fetch()
+            case .failed(let networkReachable):
+                if let networkReachable = networkReachable, networkReachable  {
+                    self.storage.add(deadContracts: [DeletedContract(contract: contract)])
+                }
             }
         }
     }
@@ -153,11 +160,13 @@ class TokensCoordinator: Coordinator {
         tokensViewController.fetch()
     }
 
+    /// Failure to obtain contract data may be due to no-connectivity. So we should check .failed(networkReachable: Bool)
     private func fetchContractData(for address: String, completion: @escaping (ContractData) -> Void) {
         var completedName: String?
         var completedSymbol: String?
         var completedBalance: [String]?
         var completedDecimals: UInt8?
+        var failed = false
 
         func callCompletionOnAllData() {
             if let completedName = completedName, let completedSymbol = completedSymbol, let completedBalance = completedBalance {
@@ -167,6 +176,13 @@ class TokensCoordinator: Coordinator {
             }
         }
 
+        func callCompletionFailed() {
+            guard !failed else { return }
+            failed = true
+            //TODO maybe better to share an instance of the reachability manager
+            completion(.failed(networkReachable: NetworkReachabilityManager()?.isReachable))
+        }
+
         self.storage.getContractName(for: address) { result in
             switch result {
             case .success(let name):
@@ -174,7 +190,7 @@ class TokensCoordinator: Coordinator {
                 completion(.name(name))
                 callCompletionOnAllData()
             case .failure:
-                break
+                callCompletionFailed()
             }
         }
 
@@ -185,7 +201,7 @@ class TokensCoordinator: Coordinator {
                 completion(.symbol(symbol))
                 callCompletionOnAllData()
             case .failure:
-                break
+                callCompletionFailed()
             }
         }
 
@@ -200,7 +216,7 @@ class TokensCoordinator: Coordinator {
                             completion(.balance(balance))
                             callCompletionOnAllData()
                         case .failure:
-                            break
+                            callCompletionFailed()
                         }
                     }
                 } else {
@@ -211,7 +227,7 @@ class TokensCoordinator: Coordinator {
                             completion(.decimals(decimal))
                             callCompletionOnAllData()
                         case .failure:
-                            break
+                            callCompletionFailed()
                         }
                     }
                 }
@@ -223,7 +239,7 @@ class TokensCoordinator: Coordinator {
                         completion(.decimals(decimal))
                         callCompletionOnAllData()
                     case .failure:
-                        break
+                        callCompletionFailed()
                     }
                 }
             }
@@ -287,6 +303,8 @@ extension TokensCoordinator: NewTokenViewControllerDelegate {
                 break
             case .nonStormBirdComplete:
                 break
+            case .failed:
+                break
             }
         }
     }

AlphaWallet/Tokens/Types/DeletedContract.swift

@@ -0,0 +1,13 @@
+// Copyright © 2018 Stormbird PTE. LTD.
+
+import Foundation
+import RealmSwift
+
+class DeletedContract: Object {
+    @objc dynamic var contract: String = ""
+
+    convenience init(contract: String) {
+        self.init()
+        self.contract = contract
+    }
+}

AlphaWallet/Tokens/Types/TokensDataStore.swift

@@ -109,6 +109,10 @@ class TokensDataStore {
             .filter { !$0.isDisabled }
     }
 
+    var deletedContracts: [DeletedContract] {
+        return Array(realm.objects(DeletedContract.self))
+    }
+
     static func update(in realm: Realm, tokens: [Token]) {
         realm.beginWrite()
         for token in tokens {
@@ -282,6 +286,12 @@ class TokensDataStore {
         }
     }
 
+    func add(deadContracts: [DeletedContract]) {
+        try! realm.write {
+            realm.add(deadContracts, update: false)
+        }
+    }
+
     @discardableResult
     func add(tokens: [TokenObject]) -> [TokenObject] {
         realm.beginWrite()