Merge branch 'charlesmchen/firstSendVsLinkedDevices'

Signal/src/ViewControllers/OWSLinkDeviceViewController.m

@@ -9,6 +9,7 @@
 #import "OWSProfileManager.h"
 #import "Signal-Swift.h"
 #import <SignalServiceKit/ECKeyPair+OWSPrivateKey.h>
+#import <SignalServiceKit/OWSDevice.h>
 #import <SignalServiceKit/OWSDeviceProvisioner.h>
 #import <SignalServiceKit/OWSIdentityManager.h>
 #import <SignalServiceKit/OWSReadReceiptManager.h>
@@ -18,9 +19,10 @@ NS_ASSUME_NONNULL_BEGIN
 
 @interface OWSLinkDeviceViewController ()
 
-@property (strong, nonatomic) IBOutlet UIView *qrScanningView;
-@property (strong, nonatomic) IBOutlet UILabel *scanningInstructionsLabel;
-@property (strong, nonatomic) OWSQRCodeScanningViewController *qrScanningController;
+@property (nonatomic) YapDatabaseConnection *dbConnection;
+@property (nonatomic) IBOutlet UIView *qrScanningView;
+@property (nonatomic) IBOutlet UILabel *scanningInstructionsLabel;
+@property (nonatomic) OWSQRCodeScanningViewController *qrScanningController;
 @property (nonatomic, readonly) OWSReadReceiptManager *readReceiptManager;
 
 @end
@@ -31,6 +33,8 @@ NS_ASSUME_NONNULL_BEGIN
 {
     [super viewDidLoad];
 
+    self.dbConnection = [[TSStorageManager sharedManager] newDatabaseConnection];
+
     // HACK to get full width preview layer
     CGRect oldFrame = self.qrScanningView.frame;
     self.qrScanningView.frame = CGRectMake(
@@ -142,6 +146,9 @@ NS_ASSUME_NONNULL_BEGIN
 
 - (void)provisionWithParser:(OWSDeviceProvisioningURLParser *)parser
 {
+    // Optimistically set this flag.
+    [OWSDeviceManager.sharedManager setMayHaveLinkedDevices:YES dbConnection:self.dbConnection];
+
     ECKeyPair *_Nullable identityKeyPair = [[OWSIdentityManager sharedManager] identityKeyPair];
     OWSAssert(identityKeyPair);
     NSData *myPublicKey = identityKeyPair.publicKey;

Signal/src/ViewControllers/OWSLinkedDevicesTableViewController.m

@@ -20,10 +20,10 @@ NS_ASSUME_NONNULL_BEGIN
 
 @interface OWSLinkedDevicesTableViewController ()
 
-@property YapDatabaseConnection *dbConnection;
-@property YapDatabaseViewMappings *deviceMappings;
-@property NSTimer *pollingRefreshTimer;
-@property BOOL isExpectingMoreDevices;
+@property (nonatomic) YapDatabaseConnection *dbConnection;
+@property (nonatomic) YapDatabaseViewMappings *deviceMappings;
+@property (nonatomic) NSTimer *pollingRefreshTimer;
+@property (nonatomic) BOOL isExpectingMoreDevices;
 
 @end
 
@@ -131,6 +131,14 @@ int const OWSLinkedDevicesTableViewControllerSectionAddDevice = 1;
     __weak typeof(self) wself = self;
     dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
         [[OWSDevicesService new] getDevicesWithSuccess:^(NSArray<OWSDevice *> *devices) {
+            // If we have more than one device; we may have a linked device.
+            if (devices.count > 1) {
+                // Setting this flag here shouldn't be necessary, but we do so
+                // because the "cost" is low and it will improve robustness.
+                [OWSDevice setMayHaveLinkedDevices:YES
+                                      dbConnection:[[TSStorageManager sharedManager] newDatabaseConnection]];
+            }
+
             if (devices.count > [OWSDevice numberOfKeysInCollection]) {
                 // Got our new device, we can stop refreshing.
                 wself.isExpectingMoreDevices = NO;
@@ -243,7 +251,6 @@ int const OWSLinkedDevicesTableViewControllerSectionAddDevice = 1;
             return (NSInteger)[self.deviceMappings numberOfItemsInSection:(NSUInteger)section];
         case OWSLinkedDevicesTableViewControllerSectionAddDevice:
             return 1;
-
         default:
             DDLogError(@"Unknown section: %ld", (long)section);
             return 0;

SignalServiceKit/src/Contacts/SignalRecipient.h

@@ -21,7 +21,7 @@ NS_ASSUME_NONNULL_BEGIN
 - (void)removeDevices:(NSSet *)set;
 
 @property (nonatomic, nullable) NSString *relay;
-@property (nonatomic, retain) NSMutableOrderedSet *devices;
+@property (nonatomic) NSMutableOrderedSet *devices;
 
 - (BOOL)supportsVoice;
 // This property indicates support for both WebRTC audio and video calls.

SignalServiceKit/src/Contacts/SignalRecipient.m

@@ -23,7 +23,23 @@ NS_ASSUME_NONNULL_BEGIN
         return self;
     }
 
-    _devices = [NSMutableOrderedSet orderedSetWithObject:[NSNumber numberWithInt:1]];
+    OWSAssert([TSAccountManager localNumber].length > 0);
+    if ([[TSAccountManager localNumber] isEqualToString:textSecureIdentifier]) {
+        // Default to no devices.
+        //
+        // This instance represents our own account and is used for sending
+        // sync message to linked devices.  We shouldn't have any linked devices
+        // yet when we create the "self" SignalRecipient, and we don't need to
+        // send sync messages to the primary - we ARE the primary.
+        _devices = [NSMutableOrderedSet new];
+    } else {
+        // Default to sending to just primary device.
+        //
+        // OWSMessageSender will correct this if it is wrong the next time
+        // we send a message to this recipient.
+        _devices = [NSMutableOrderedSet orderedSetWithObject:@(1)];
+    }
+
     _relay = [relay isEqualToString:@""] ? nil : relay;
 
     return self;

SignalServiceKit/src/Devices/OWSDevice.h

@@ -9,12 +9,25 @@ NS_ASSUME_NONNULL_BEGIN
 
 extern uint32_t const OWSDevicePrimaryDeviceId;
 
+@interface OWSDeviceManager : NSObject
+
+- (instancetype)init NS_UNAVAILABLE;
+
++ (instancetype)sharedManager;
+
+- (BOOL)mayHaveLinkedDevices:(YapDatabaseConnection *)dbConnection;
+- (void)setMayHaveLinkedDevices:(BOOL)value dbConnection:(YapDatabaseConnection *)dbConnection;
+
+@end
+
+#pragma mark -
+
 @interface OWSDevice : TSYapDatabaseObject <MTLJSONSerializing>
 
 @property (nonatomic, readonly) NSInteger deviceId;
-@property (nullable, readonly) NSString *name;
-@property (readonly) NSDate *createdAt;
-@property (readonly) NSDate *lastSeenAt;
+@property (nonatomic, readonly, nullable) NSString *name;
+@property (nonatomic, readonly) NSDate *createdAt;
+@property (nonatomic, readonly) NSDate *lastSeenAt;
 
 + (instancetype)deviceFromJSONDictionary:(NSDictionary *)deviceAttributes error:(NSError **)error;
 

SignalServiceKit/src/Devices/OWSDevice.m

@@ -5,26 +5,90 @@
 #import "OWSDevice.h"
 #import "NSDate+OWS.h"
 #import "OWSError.h"
+#import "TSStorageManager.h"
 #import "YapDatabaseConnection.h"
 #import "YapDatabaseTransaction.h"
 #import <Mantle/MTLValueTransformer.h>
 
 NS_ASSUME_NONNULL_BEGIN
 
-static MTLValueTransformer *_millisecondTimestampToDateTransformer;
 uint32_t const OWSDevicePrimaryDeviceId = 1;
+NSString *const kTSStorageManager_OWSDeviceCollection = @"kTSStorageManager_OWSDeviceCollection";
+NSString *const kTSStorageManager_MayHaveLinkedDevices = @"kTSStorageManager_MayHaveLinkedDevices";
+
+@interface OWSDeviceManager ()
+
+@property (atomic, nullable) NSNumber *mayHaveLinkedDevicesCached;
+
+@end
+
+#pragma mark -
+
+@implementation OWSDeviceManager
+
++ (instancetype)sharedManager
+{
+    static OWSDeviceManager *instance = nil;
+    static dispatch_once_t onceToken;
+    dispatch_once(&onceToken, ^{
+        instance = [[self alloc] initDefault];
+    });
+    return instance;
+}
+
+- (instancetype)initDefault
+{
+    return [super init];
+}
+
+- (BOOL)mayHaveLinkedDevices:(YapDatabaseConnection *)dbConnection
+{
+    OWSAssert(dbConnection);
+
+    @synchronized(self)
+    {
+        if (!self.mayHaveLinkedDevicesCached) {
+            self.mayHaveLinkedDevicesCached = @([dbConnection boolForKey:kTSStorageManager_MayHaveLinkedDevices
+                                                            inCollection:kTSStorageManager_OWSDeviceCollection
+                                                            defaultValue:YES]);
+        }
+
+        return [self.mayHaveLinkedDevicesCached boolValue];
+    }
+}
+
+- (void)setMayHaveLinkedDevices:(BOOL)value dbConnection:(YapDatabaseConnection *)dbConnection
+{
+    OWSAssert(dbConnection);
+
+    @synchronized(self)
+    {
+        self.mayHaveLinkedDevicesCached = @(value);
+
+        [dbConnection asyncReadWriteWithBlock:^(YapDatabaseReadWriteTransaction *_Nonnull transaction) {
+            [transaction setObject:@(value)
+                            forKey:kTSStorageManager_MayHaveLinkedDevices
+                      inCollection:kTSStorageManager_OWSDeviceCollection];
+        }];
+    }
+}
+
+@end
+
+#pragma mark -
 
 @interface OWSDevice ()
 
-@property NSString *name;
-@property NSDate *createdAt;
-@property NSDate *lastSeenAt;
+@property (nonatomic) NSInteger deviceId;
+@property (nonatomic, nullable) NSString *name;
+@property (nonatomic) NSDate *createdAt;
+@property (nonatomic) NSDate *lastSeenAt;
 
 @end
 
-@implementation OWSDevice
+#pragma mark -
 
-@synthesize name = _name;
+@implementation OWSDevice
 
 + (instancetype)deviceFromJSONDictionary:(NSDictionary *)deviceAttributes error:(NSError **)error
 {
@@ -76,9 +140,10 @@ uint32_t const OWSDevicePrimaryDeviceId = 1;
 
 + (MTLValueTransformer *)millisecondTimestampToDateTransformer
 {
-    if (!_millisecondTimestampToDateTransformer) {
-        _millisecondTimestampToDateTransformer =
-            [MTLValueTransformer transformerUsingForwardBlock:^id(id value, BOOL *success, NSError **error) {
+    static MTLValueTransformer *instance = nil;
+    static dispatch_once_t onceToken;
+    dispatch_once(&onceToken, ^{
+        instance = [MTLValueTransformer transformerUsingForwardBlock:^id(id value, BOOL *success, NSError **error) {
             if ([value isKindOfClass:[NSNumber class]]) {
                 NSNumber *number = (NSNumber *)value;
                 NSDate *result = [NSDate ows_dateWithMillisecondsSince1970:[number longLongValue]];
@@ -106,8 +171,8 @@ uint32_t const OWSDevicePrimaryDeviceId = 1;
                 *success = NO;
                 return nil;
             }];
-    }
-    return _millisecondTimestampToDateTransformer;
+    });
+    return instance;
 }
 
 + (uint32_t)currentDeviceId

SignalServiceKit/src/Messages/OWSMessageSender.m

@@ -954,14 +954,29 @@ NSString *const OWSMessageSenderRateLimitedException = @"RateLimitedException";
 
     NSString *localNumber = [TSAccountManager localNumber];
     if ([localNumber isEqualToString:recipient.uniqueId]) {
-        __block BOOL hasSecondaryDevices;
-        [self.dbConnection readWithBlock:^(YapDatabaseReadTransaction *transaction) {
-            hasSecondaryDevices = [OWSDevice hasSecondaryDevicesWithTransaction:transaction];
-        }];
+        OWSAssert([message isKindOfClass:[OWSOutgoingSyncMessage class]]);
+        // Messages send to the "local number" should be sync messages.
+        //
+        // We can skip sending sync messages if we know that we have no linked
+        // devices. However, we need to be sure to handle the case where the
+        // linked device list has just changed.
+        //
+        // The linked device list is reflected in two separate pieces of state:
+        //
+        // * OWSDevice's state is updated when you link or unlink a device.
+        // * SignalRecipient's state is updated by 409 "Mismatched devices"
+        //   responses from the service.
+        //
+        // If _both_ of these pieces of state agree that there are no linked
+        // devices, then can safely skip sending sync message.
 
+        // 1. Check OWSDevice's state.
+        BOOL mayHaveLinkedDevices = [OWSDeviceManager.sharedManager mayHaveLinkedDevices:self.dbConnection];
+
+        // 2. Check SignalRecipient's state.
         BOOL hasDeviceMessages = deviceMessages.count > 0;
 
-        if (!hasSecondaryDevices && !hasDeviceMessages) {
+        if (!mayHaveLinkedDevices && !hasDeviceMessages) {
             DDLogInfo(@"%@ Ignoring sync message without secondary devices: %@", self.logTag, [message class]);
             OWSAssert([message isKindOfClass:[OWSOutgoingSyncMessage class]]);
 
@@ -972,10 +987,10 @@ NSString *const OWSMessageSenderRateLimitedException = @"RateLimitedException";
             });
 
             return;
-        } else if (hasSecondaryDevices) {
+        } else if (mayHaveLinkedDevices) {
             // We may have just linked a new secondary device which is not yet reflected in
             // the SignalRecipient that corresponds to ourself.  Proceed.  Client should learn
-            // of new secondary devices when this message send fails.
+            // of new secondary devices via 409 "Mismatched devices" response.
             DDLogWarn(@"%@ sync message has no device messages but account has secondary devices.", self.logTag);
         } else if (hasDeviceMessages) {
             OWSFail(@"%@ sync message has device messages for unknown secondary devices.", self.logTag);
@@ -1095,6 +1110,13 @@ NSString *const OWSMessageSenderRateLimitedException = @"RateLimitedException";
     NSArray *extraDevices = [dictionary objectForKey:@"extraDevices"];
     NSArray *missingDevices = [dictionary objectForKey:@"missingDevices"];
 
+    if (missingDevices.count > 0) {
+        NSString *localNumber = [TSAccountManager localNumber];
+        if ([localNumber isEqualToString:recipient.uniqueId]) {
+            [OWSDeviceManager.sharedManager setMayHaveLinkedDevices:YES dbConnection:self.dbConnection];
+        }
+    }
+
     dispatch_async([OWSDispatch sessionStoreQueue], ^{
         if (extraDevices.count < 1 && missingDevices.count < 1) {
             OWSProdFail([OWSAnalyticsEvents messageSenderErrorNoMissingOrExtraDevices]);

SignalServiceKit/src/Storage/YapDatabaseConnection+OWS.h

@@ -14,6 +14,7 @@ NS_ASSUME_NONNULL_BEGIN
 
 - (BOOL)hasObjectForKey:(NSString *)key inCollection:(NSString *)collection;
 - (BOOL)boolForKey:(NSString *)key inCollection:(NSString *)collection;
+- (BOOL)boolForKey:(NSString *)key inCollection:(NSString *)collection defaultValue:(BOOL)defaultValue;
 - (int)intForKey:(NSString *)key inCollection:(NSString *)collection;
 - (nullable id)objectForKey:(NSString *)key inCollection:(NSString *)collection;
 - (nullable NSDate *)dateForKey:(NSString *)key inCollection:(NSString *)collection;

SignalServiceKit/src/Storage/YapDatabaseConnection+OWS.m

@@ -52,8 +52,13 @@ NS_ASSUME_NONNULL_BEGIN
 
 - (BOOL)boolForKey:(NSString *)key inCollection:(NSString *)collection
 {
-    NSNumber *_Nullable number = [self objectForKey:key inCollection:collection ofExpectedType:[NSNumber class]];
-    return [number boolValue];
+    return [self boolForKey:key inCollection:collection defaultValue:NO];
+}
+
+- (BOOL)boolForKey:(NSString *)key inCollection:(NSString *)collection defaultValue:(BOOL)defaultValue
+{
+    NSNumber *_Nullable value = [self objectForKey:key inCollection:collection ofExpectedType:[NSNumber class]];
+    return value ? [value boolValue] : defaultValue;
 }
 
 - (nullable NSData *)dataForKey:(NSString *)key inCollection:(NSString *)collection