Add max message size

Source/ARTBaseMessage.h

@@ -7,6 +7,7 @@
 //
 
 #import <Foundation/Foundation.h>
+#import <Ably/ARTTypes.h>
 
 NS_ASSUME_NONNULL_BEGIN
 
@@ -29,8 +30,14 @@ NS_ASSUME_NONNULL_BEGIN
 
 @property (strong, nonatomic, nullable) id data;
 
+/// The event name, if available
+@property (nullable, readwrite, strong, nonatomic) NSString *name;
+@property (nullable, nonatomic) id<ARTJsonCompatible> extras;
+
 - (NSString *)description;
 
+- (NSInteger)messageSize;
+
 @end
 
 NS_ASSUME_NONNULL_END

Source/ARTBaseMessage.m

@@ -69,4 +69,29 @@ - (NSString *)description {
     return description;
 }
 
+- (NSInteger)messageSize {
+    // TO3l8*
+    NSInteger finalResult = 0;
+    finalResult += [self.name lengthOfBytesUsingEncoding:NSUTF8StringEncoding];
+    finalResult += [[self.extras toJSONString] lengthOfBytesUsingEncoding:NSUTF8StringEncoding];
+    finalResult += [self.clientId lengthOfBytesUsingEncoding:NSUTF8StringEncoding];
+    if (self.data) {
+        if ([self.data isKindOfClass:[NSString class]]) {
+            finalResult += [self.data lengthOfBytesUsingEncoding:NSUTF8StringEncoding];
+        }
+        else if ([self.data isKindOfClass:[NSData class]]) {
+            finalResult += [self.data length];
+        } else {
+            NSError *error = nil;
+            NSData *jsonData = [NSJSONSerialization dataWithJSONObject:self.data
+                                                               options:NSJSONWritingPrettyPrinted
+                                                                 error:&error];
+            if (!error) {
+                finalResult += [jsonData length];
+            }
+        }
+    }
+    return finalResult;
+}
+
 @end

Source/ARTChannel.h

@@ -15,6 +15,7 @@
 @class ARTRest;
 @class ARTChannelOptions;
 @class ARTMessage;
+@class ARTBaseMessage;
 @class ARTPaginatedResult<ItemType>;
 @class ARTDataQuery;
 
@@ -43,6 +44,7 @@ NS_ASSUME_NONNULL_BEGIN
 
 - (void)history:(void(^)(ARTPaginatedResult<ARTMessage *> *_Nullable result, ARTErrorInfo *_Nullable error))callback;
 
+- (BOOL)exceedMaxSize:(NSArray<ARTBaseMessage *> *)messages;
 @end
 
 NS_ASSUME_NONNULL_END

Source/ARTChannel.m

@@ -15,6 +15,7 @@
 #import "ARTBaseMessage+Private.h"
 #import "ARTDataQuery.h"
 #import "ARTRest+Private.h"
+#import "ARTDefault.h"
 
 @implementation ARTChannel {
     __weak ARTRest *_rest;
@@ -73,6 +74,17 @@ - (void)publish:(art_nullable NSString *)name data:(art_nullable id)data extras:
         if (callback) callback([ARTErrorInfo createFromNSError:error]);
         return;
     }
+
+    // Checked after encoding, so that the client can receive callback with encoding errors
+    if ([self exceedMaxSize:@[message]]) {
+        ARTErrorInfo *sizeError = [ARTErrorInfo createWithCode:40009
+                                                       message:@"maximum message length exceeded"];
+        if (callback) {
+            callback(sizeError);
+        }
+        return;
+    }
+
     [self internalPostMessages:messagesWithDataEncoded callback:callback];
 }
 
@@ -97,6 +109,17 @@ - (void)publish:(NSString *)name data:(id)data clientId:(NSString *)clientId ext
         if (callback) callback([ARTErrorInfo createFromNSError:error]);
         return;
     }
+
+    // Checked after encoding, so that the client can receive callback with encoding errors
+    if ([self exceedMaxSize:@[message]]) {
+        ARTErrorInfo *sizeError = [ARTErrorInfo createWithCode:40009
+                                                       message:@"maximum message length exceeded"];
+        if (callback) {
+            callback(sizeError);
+        }
+        return;
+    }
+
     [self internalPostMessages:messagesWithDataEncoded callback:callback];
 }
 
@@ -106,6 +129,7 @@ - (void)publish:(NSArray<ARTMessage *> *)messages {
 
 - (void)publish:(__GENERIC(NSArray, ARTMessage *) *)messages callback:(art_nullable void (^)(ARTErrorInfo *__art_nullable error))callback {
     NSError *error = nil;
+
     NSMutableArray<ARTMessage *> *messagesWithDataEncoded = [NSMutableArray new];
     for (ARTMessage *message in messages) {
         [messagesWithDataEncoded addObject:[self encodeMessageIfNeeded:message error:&error]];
@@ -114,9 +138,28 @@ - (void)publish:(__GENERIC(NSArray, ARTMessage *) *)messages callback:(art_nulla
         callback([ARTErrorInfo createFromNSError:error]);
         return;
     }
+
+    // Checked after encoding, so that the client can receive callback with encoding errors
+    if ([self exceedMaxSize:messages]) {
+        ARTErrorInfo *sizeError = [ARTErrorInfo createWithCode:40009
+                                                       message:@"maximum message length exceeded"];
+        if (callback) {
+            callback(sizeError);
+        }
+        return;
+    }
+
     [self internalPostMessages:messagesWithDataEncoded callback:callback];
 }
 
+- (BOOL)exceedMaxSize:(NSArray<ARTBaseMessage *> *)messages {
+    NSInteger size = 0;
+    for (ARTMessage *message in messages) {
+        size += [message messageSize];
+    }
+    return size > [ARTDefault maxMessageSize];
+}
+
 - (ARTMessage *)encodeMessageIfNeeded:(ARTMessage *)message error:(NSError **)error {
     if (!self.dataEncoder) {
         return message;

Source/ARTConnection+Private.h

@@ -31,6 +31,7 @@ NS_ASSUME_NONNULL_BEGIN
 - (void)setId:(NSString *_Nullable)newId;
 - (void)setKey:(NSString *_Nullable)key;
 - (void)setSerial:(int64_t)serial;
+- (void)setMaxMessageSize:(NSInteger)maxMessageSize;
 - (void)setState:(ARTRealtimeConnectionState)state;
 - (void)setErrorReason:(ARTErrorInfo *_Nullable)errorReason;
 

Source/ARTConnection.h

@@ -21,6 +21,7 @@ NS_ASSUME_NONNULL_BEGIN
 @property (nullable, readonly, strong, nonatomic) NSString *key;
 @property (nullable, readonly, getter=getRecoveryKey) NSString *recoveryKey;
 @property (readonly, assign, nonatomic) int64_t serial;
+@property (readonly, assign, nonatomic) NSInteger maxMessageSize;
 @property (readonly, assign, nonatomic) ARTRealtimeConnectionState state;
 @property (nullable, readonly, strong, nonatomic) ARTErrorInfo *errorReason;
 

Source/ARTConnection.m

@@ -20,6 +20,7 @@ @implementation ARTConnection {
     _Nonnull dispatch_queue_t _queue;
     NSString *_id;
     NSString *_key;
+    NSInteger _maxMessageSize;
     int64_t _serial;
     ARTRealtimeConnectionState _state;
     ARTErrorInfo *_errorReason;
@@ -135,6 +136,12 @@ - (void)setSerial:(int64_t)serial {
 } ART_TRY_OR_MOVE_TO_FAILED_END
 }
 
+- (void)setMaxMessageSize:(NSInteger)maxMessageSize {
+ART_TRY_OR_MOVE_TO_FAILED_START(_realtime) {
+    _maxMessageSize = maxMessageSize;
+} ART_TRY_OR_MOVE_TO_FAILED_END
+}
+
 - (void)setState:(ARTRealtimeConnectionState)state {
 ART_TRY_OR_MOVE_TO_FAILED_START(_realtime) {
     _state = state;

Source/ARTMessage.h

@@ -15,10 +15,6 @@ NS_ASSUME_NONNULL_BEGIN
 
 @interface ARTMessage : ARTBaseMessage
 
-/// The event name, if available
-@property (nullable, readwrite, strong, nonatomic) NSString *name;
-@property (nullable, nonatomic) id<ARTJsonCompatible> extras;
-
 - (instancetype)initWithName:(nullable NSString *)name data:(id)data;
 - (instancetype)initWithName:(nullable NSString *)name data:(id)data clientId:(NSString *)clientId;
 

Source/ARTMessage.m

@@ -12,7 +12,7 @@ @implementation ARTMessage
 
 - (instancetype)initWithName:(NSString *)name data:(id)data {
     if (self = [self init]) {
-        _name = [name copy];
+        self.name = [name copy];
         if (data) {
             self.data = data;
             self.encoding = @"";
@@ -42,8 +42,8 @@ - (NSString *)description {
 
 - (id)copyWithZone:(NSZone *)zone {
     ARTMessage *message = [super copyWithZone:zone];
-    message->_name = self.name;
-    message->_extras = self.extras;
+    message.name = self.name;
+    message.extras = self.extras;
     return message;
 }
 

Source/ARTRealtime.m

@@ -613,6 +613,7 @@ - (void)onConnected:(ARTProtocolMessage *)message {
         case ARTRealtimeConnecting:
             [self.connection setId:message.connectionId];
             [self.connection setKey:message.connectionKey];
+            [self.connection setMaxMessageSize:message.connectionDetails.maxMessageSize];
             if (!_resuming) {
                 [self.connection setSerial:message.connectionSerial];
                 [self.logger debug:@"RT:%p msgSerial of connection \"%@\" has been reset", self, self.connection.id_nosync];

Source/ARTRealtimeChannel.m

@@ -178,6 +178,16 @@ - (void)publishPresence:(ARTPresenceMessage *)msg callback:(art_nullable void (^
         if (cb) cb([ARTErrorInfo createWithCode:ARTStateNoClientId message:@"attempted to publish presence message without clientId"]);
         return;
     }
+
+    if ([self exceedMaxSize:@[msg]]) {
+        if (cb) {
+            ARTErrorInfo *sizeError = [ARTErrorInfo createWithCode:40009
+                                                           message:@"maximum message length exceeded"];
+            cb(sizeError);
+        }
+        return;
+    }
+
     _lastPresenceAction = msg.action;
 
     if (msg.data && self.dataEncoder) {
@@ -1096,6 +1106,18 @@ - (void)map:(ARTPresenceMap *)map shouldReenterLocalMember:(ARTPresenceMessage *
 } ART_TRY_OR_MOVE_TO_FAILED_END
 }
 
+- (BOOL)exceedMaxSize:(NSArray<ARTBaseMessage *> *)messages {
+    NSInteger size = 0;
+    for (ARTMessage *message in messages) {
+        size += [message messageSize];
+    }
+    NSInteger maxSize = [ARTDefault maxMessageSize];
+    if (self.realtime.connection.maxMessageSize) {
+        maxSize = self.realtime.connection.maxMessageSize;
+    }
+    return size > maxSize;
+}
+
 @end
 
 #pragma mark - ARTEvent

Source/ARTTypes.h

@@ -178,6 +178,7 @@ NSString *generateNonce(void);
 
 @protocol ARTJsonCompatible <NSObject>
 - (NSDictionary *_Nullable)toJSON:(NSError *_Nullable *_Nullable)error;
+- (NSString *_Nullable)toJSONString;
 @end
 
 @interface NSString (ARTEventIdentification) <ARTEventIdentification>

Source/ARTTypes.m

@@ -175,6 +175,10 @@ - (NSDictionary *)toJSON:(NSError *_Nullable *_Nullable)error {
     return (NSDictionary *)json;
 }
 
+- (NSString *)toJSONString {
+    return self;
+}
+
 @end
 
 @implementation NSDictionary (ARTJsonCompatible)
@@ -186,6 +190,16 @@ - (NSDictionary *)toJSON:(NSError *_Nullable *_Nullable)error {
     return self;
 }
 
+- (NSString *)toJSONString {
+    NSError *err = nil;
+    NSData *jsonData = [NSJSONSerialization dataWithJSONObject:self options:0 error:&err];
+    if (err) {
+        return nil;
+    }
+    NSString *jsonString = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];
+    return jsonString;
+}
+
 @end
 
 @implementation NSURL (ARTLog)