AFNetworking 后台会话 KVO 错误答案

【问题标题】：AFNetworking Background Session KVO ErrorAFNetworking 后台会话 KVO 错误
【发布时间】：2016-03-10 01:50:16
【问题描述】：

有时我的应用会在启动时崩溃。

似乎与后台 NSURL Session Activity 失败有关。此消息在 Crashlytics 日志中的出现相当一致：

_block_invoke line 233 $ Error Domain=NSURLErrorDomain Code=-997 "Lost connection to background transfer service"

我不知道如何在 xCode 中调试此问题，因为我无法在我的测试设备连接到我的计算机时导致它发生。

我没有在我的应用程序中使用 KVO；也许这是 AFNetworking 本身的问题？

以下是 Crashlytics 报告的崩溃消息：

Fatal Exception: NSInternalInconsistencyException
An instance 0x14f97ef00 of class __NSCFBackgroundDataTask was deallocated while 
key value observers were still registered with it. 
Current observation info: <NSKeyValueObservationInfo 0x14f97f320> ( <NSKeyValueObservance 0x14f841ea0: Observer: 0x14e777340, Key path: countOfBytesReceived, Options: <New: YES, Old: NO, Prior: NO> Context: 0x0, Property: 0x14e650010> <NSKeyValueObservance 0x14e6e1770: Observer: 0x14e777340, Key path: countOfBytesExpectedToReceive, Options: <New: YES, Old: NO, Prior: NO> Context: 0x0, Property: 0x14f81c090> <NSKeyValueObservance 0x14f80e030: Observer: 0x14e777340, Key path: countOfBytesSent, Options: <New: YES, Old: NO, Prior: NO> Context: 0x0, Property: 0x14f97e880> <NSKeyValueObservance 0x14e5ca9c0: Observer: 0x14e777340, Key path: countOfBytesExpectedToSend, Options: <New: YES, Old: NO, Prior: NO> Context: 0x0, Property: 0x14f97cf20> )

任何帮助将不胜感激。

【问题讨论】：

我认为这可能是由重复的 GET 请求引起的。
见github.com/AFNetworking/AFNetworking/issues/3380，这可能对你有帮助。
我认为这将在他们发布 AFNetworking 3.1.1 时得到修复（3.1.0 是当前版本。）我们将向后移植这个修复：github.com/AFNetworking/AFNetworking/commit/…
添加这个以防它帮助其他人找到这个 SO 问题

标签： ios key-value-observing afnetworking-3

【解决方案1】：

见https://github.com/AFNetworking/AFNetworking/issues/3380

我认为这会在他们发布 AFNetworking 3.1.1 时得到解决（3.1.0 是当前版本。）

Backporting https://github.com/AFNetworking/AFNetworking/commit/ff228fad3addd141cc668891b6c3bb9b1b1c4271.patch 为我解决了这个问题。

添加这个以防其他人找到这个问题

Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'An instance 0x7fdcb4d099f0 of class __NSCFBackgroundDataTask was deallocated while key value observers were still registered with it. Current observation info: <NSKeyValueObservationInfo 0x60000002da80> (
<NSKeyValueObservance 0x60000005b2d0: Observer: 0x600000283110, Key path: countOfBytesReceived, Options: <New: YES, Old: NO, Prior: NO> Context: 0x0, Property: 0x60000005b300>
<NSKeyValueObservance 0x60000005b660: Observer: 0x600000283110, Key path: countOfBytesExpectedToReceive, Options: <New: YES, Old: NO, Prior: NO> Context: 0x0, Property: 0x60000005b690>
<NSKeyValueObservance 0x60000005b870: Observer: 0x600000283110, Key path: countOfBytesSent, Options: <New: YES, Old: NO, Prior: NO> Context: 0x0, Property: 0x60000005b8a0>
<NSKeyValueObservance 0x60000005ba20: Observer: 0x600000283110, Key path: countOfBytesExpectedToSend, Options: <New: YES, Old: NO, Prior: NO> Context: 0x0, Property: 0x60000005ba50>

【讨论】：