AFHTTPRequestSerializer 请求序列化
初始化，大概干了这么些事情
- Accept-Language ：前五种语言
- User-Agent ：项目名称？：bundleID 版本号 model ios 系统号 scale
- 监听暴漏在外部的六个属性
self.stringEncoding = NSUTF8StringEncoding;
self.mutableHTTPRequestHeaders = [NSMutableDictionary dictionary];
self.requestHeaderModificationQueue = dispatch_queue_create("requestHeaderModificationQueue", DISPATCH_QUEUE_CONCURRENT);
NSMutableArray *acceptLanguagesComponents = [NSMutableArray array];
///获取前五中语言
[[NSLocale preferredLanguages] enumerateObjectsUsingBlock:^(NSString * _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
float q = 1.0f - (idx *0.1f);
[acceptLanguagesComponents addObject:[NSString stringWithFormat:@"%@;q=%0.1g",obj,q]];
*stop = q<=0.5f;
}];
///设置前五种语言
[self setValue:[acceptLanguagesComponents componentsJoinedByString:@", "] forHTTPHeaderField:@"Accept-Language"];
NSString *userAgent = nil;
#if TARGET_OS_IOS
///ebooksystem /4.0.0 (iPhone; iOS 13.3; Scale/2.00) ios.zaxue.zaxue_ios
///项目名称？：bundleID 版本号 model ios 系统号 scale
userAgent = [NSString stringWithFormat:@"%@/%@ (%@; iOS %@; Scale/%0.2f)", [[NSBundle mainBundle] infoDictionary][(__bridge NSString *)kCFBundleExecutableKey] ?: [[NSBundle mainBundle] infoDictionary][(__bridge NSString *)kCFBundleIdentifierKey], [[NSBundle mainBundle] infoDictionary][@"CFBundleShortVersionString"] ?: [[NSBundle mainBundle] infoDictionary][(__bridge NSString *)kCFBundleVersionKey], [[UIDevice currentDevice] model], [[UIDevice currentDevice] systemVersion], [[UIScreen mainScreen] scale]];
#elif TARGET_OS_WATCH
// User-Agent Header; see http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.43
userAgent = [NSString stringWithFormat:@"%@/%@ (%@; watchOS %@; Scale/%0.2f)", [[NSBundle mainBundle] infoDictionary][(__bridge NSString *)kCFBundleExecutableKey] ?: [[NSBundle mainBundle] infoDictionary][(__bridge NSString *)kCFBundleIdentifierKey], [[NSBundle mainBundle] infoDictionary][@"CFBundleShortVersionString"] ?: [[NSBundle mainBundle] infoDictionary][(__bridge NSString *)kCFBundleVersionKey], [[WKInterfaceDevice currentDevice] model], [[WKInterfaceDevice currentDevice] systemVersion], [[WKInterfaceDevice currentDevice] screenScale]];
#elif defined(__MAC_OS_X_VERSION_MIN_REQUIRED)
userAgent = [NSString stringWithFormat:@"%@/%@ (Mac OS X %@)", [[NSBundle mainBundle] infoDictionary][(__bridge NSString *)kCFBundleExecutableKey] ?: [[NSBundle mainBundle] infoDictionary][(__bridge NSString *)kCFBundleIdentifierKey], [[NSBundle mainBundle] infoDictionary][@"CFBundleShortVersionString"] ?: [[NSBundle mainBundle] infoDictionary][(__bridge NSString *)kCFBundleVersionKey], [[NSProcessInfo processInfo] operatingSystemVersionString]];
#endif
if (userAgent) {
if (![userAgent canBeConvertedToEncoding:NSASCIIStringEncoding]) {
NSMutableString *mutableUserAgent = [userAgent mutableCopy];
if (CFStringTransform((__bridge CFMutableStringRef)(mutableUserAgent), NULL, (__bridge CFStringRef)@"Any-Latin; Latin-ASCII; [:^ASCII:] Remove", false)) {
userAgent = mutableUserAgent;
}
}
[self setValue:userAgent forHTTPHeaderField:@"User-Agent"];
}
self.HTTPMethodsEncodingParametersInURI = [NSSet setWithObjects:@"GET",@"HEAD",@"DELETE",nil];
self.mutableObservedChangedKeyPaths = [NSMutableSet set];
///监听六个属性
for (NSString *keyPath in AFHTTPRequestSerializerObservedKeyPaths()) {
if ([self respondsToSelector:NSSelectorFromString(keyPath)]) {
[self addObserver:self forKeyPath:keyPath options:NSKeyValueObservingOptionNew context:AFHTTPRequestSerializerObserverContext];
}
}
requestWithMethod
数据放在contentType中，直接用body上传
- (NSMutableURLRequest *)requestWithMethod:(NSString *)method
URLString:(NSString *)URLString
parameters:(id)parameters error:(NSError *__autoreleasing *)error
生成request的基本方法
- (NSURLRequest *)requestBySerializingRequest:(NSURLRequest *)request
withParameters:(id)parameters
error:(NSError *__autoreleasing *)error
multipart 流传输 用于大文件
Content-Type:multipart/form-data;boundary=
- (NSMutableURLRequest *)multipartFormRequestWithMethod:(NSString *)method
URLString:(NSString *)URLString
parameters:(NSDictionary *)parameters
constructingBodyWithBlock:(void (^)(id <AFMultipartFormData> formData))block
error:(NSError *__autoreleasing *)error { NSParameterAssert(method);
NSParameterAssert(![method isEqualToString:@"GET"] && ![method isEqualToString:@"HEAD"]);
NSMutableURLRequest *mutableRequest = [self requestWithMethod:method URLString:URLString parameters:nil error:error];
__block AFStreamingMultipartFormData *formData = [[AFStreamingMultipartFormData alloc] initWithURLRequest:mutableRequest stringEncoding:NSUTF8StringEncoding];
//将传入字典转为AFQueryStringPair
if (parameters) {
for (AFQueryStringPair *pair in AFQueryStringPairsFromDictionary(parameters)) {
NSData *data = nil;
if ([pair.value isKindOfClass:[NSData class]]) {
data = pair.value;
} else if ([pair.value isEqual:[NSNull null]]) {
data = [NSData data];
} else {
data = [[pair.value description]dataUsingEncoding:self.stringEncoding];
}
///拼接到data中
if (data) {
[formData appendPartWithFormData:data name:[pair.field description]];
}
}
}
if (block) {
block(formData);
}
///返回最终拼好流和body的 request
return [formData requestByFinalizingMultipartFormData];
}
来进一步分析里面干了些什么
- 先根据requestWithMethod:method生成一个request
NSMutableURLRequest *mutableRequest = [self requestWithMethod:method URLString:URLString parameters:nil error:error];
__block AFStreamingMultipartFormData *formData = [[AFStreamingMultipartFormData alloc] initWithURLRequest:mutableRequest stringEncoding:NSUTF8StringEncoding];
AFStreamingMultipartFormData
AFStreamingMultipartFormData干了些什么呢？
- 核心方法是这个，设置BodyStream ，其中 self.boundary 和 bodyStream是其两个属性，返回设置bodyStream 的 request
- (NSMutableURLRequest *)requestByFinalizingMultipartFormData
appendPartWithFileURL 是谁调用呢？
- 遵守 AFMultipartFormData 的代理方 外部调用 appendPartWithFileData 方法传入Data数据并将数据转为AFHTTPBodyPart 模型
然后appendHTTPBodyPart 将body 加到 AFMultipartBodyStream 的 HTTPBodyParts body数组中
AFMultipartBodyStream
用于存放AFHTTPBodyPart的数组
@property (readwrite, nonatomic, strong) NSMutableArray *HTTPBodyParts;
外部暴漏的方法
初始化stream
- (instancetype)initWithStringEncoding:(NSStringEncoding)encoding;
///HTTPBodyParts的第一个元素设置开始属性为YES，把最后一个元素设置结束属性为YES AFStreamingMultipartFormData返回Request时 和打开流 时 会调用
- (void)setInitialAndFinalBoundaries;
/// HTTPBodyParts 添加 HTTPBodyParts
- (void)appendHTTPBodyPart:(AFHTTPBodyPart *)bodyPart;
///重写了NSInputStream的 读取拼接数据
- (NSInteger)read:(uint8_t *)buffer
maxLength:(NSUInteger)length
///拼接下一段body
AFHTTPBodyPart
外部暴漏方法
///转移到下一个阶段
- (BOOL)transitionToNextPhase;
///模型拼接Data数据
- (NSInteger)readData:(NSData *)data
intoBuffer:(uint8_t *)buffer
maxLength:(NSUInteger)length;
- (BOOL)transitionToNextPhase
对Multipart请求体各部分（初始边界、头部、内容数据实体、结束边界）做拼接和读取的封装
AFHTTPRequestSerializer逻辑图
