iOS解读AFN查看请求头，判断响应成功、失败

墨蓝 2023-10-17 14:59 129阅读 0赞

AFN不管是GET、POST、PUT、DELETE请求，最终都会调用此方法 ，建立一个任务。

AFHTTPSessionManager.m

- (NSURLSessionDataTask *)dataTaskWithHTTPMethod:(NSString *)method
                                           URLString:(NSString *)URLString
                                          parameters:(id)parameters
                                      uploadProgress:(nullable void (^)(NSProgress *uploadProgress)) uploadProgress
                                    downloadProgress:(nullable void (^)(NSProgress *downloadProgress)) downloadProgress
                                             success:(void (^)(NSURLSessionDataTask *, id))success
                                             failure:(void (^)(NSURLSessionDataTask *, NSError *))failure
    {
        NSError *serializationError = nil;
        NSMutableURLRequest *request = [self.requestSerializer requestWithMethod:method URLString:[[NSURL URLWithString:URLString relativeToURL:self.baseURL] absoluteString] parameters:parameters error:&serializationError];
        if (serializationError) {
            if (failure) {
    #pragma clang diagnostic push
    #pragma clang diagnostic ignored "-Wgnu"
                dispatch_async(self.completionQueue ?: dispatch_get_main_queue(), ^{
                    failure(nil, serializationError);
                });
    #pragma clang diagnostic pop
            }
    
            return nil;
        }
    
        __block NSURLSessionDataTask *dataTask = nil;
        dataTask = [self dataTaskWithRequest:request
                              uploadProgress:uploadProgress
                            downloadProgress:downloadProgress
                           completionHandler:^(NSURLResponse * __unused response, id responseObject, NSError *error) {
            if (error) {
                if (failure) {
                    failure(dataTask, error);
                }
            } else {
                if (success) {
                    success(dataTask, responseObject);
                }
            }
        }];
    
        return dataTask;
    }

发送请求如下：

AFURLRequestSerialization.m

- (NSMutableURLRequest *)requestWithMethod:(NSString *)method
                                     URLString:(NSString *)URLString
                                    parameters:(id)parameters
                                         error:(NSError *__autoreleasing *)error
    {
        NSParameterAssert(method);
        NSParameterAssert(URLString);
    
        NSURL *url = [NSURL URLWithString:URLString];
    
        NSParameterAssert(url);
    
        NSMutableURLRequest *mutableRequest = [[NSMutableURLRequest alloc] initWithURL:url];
        mutableRequest.HTTPMethod = method;
    
        for (NSString *keyPath in AFHTTPRequestSerializerObservedKeyPaths()) {
            if ([self.mutableObservedChangedKeyPaths containsObject:keyPath]) {
                [mutableRequest setValue:[self valueForKeyPath:keyPath] forKey:keyPath];
            }
        }
    
        mutableRequest = [[self requestBySerializingRequest:mutableRequest withParameters:parameters error:error] mutableCopy];
    
    	return mutableRequest;
    }

我们在控制台输出request时，只会得到一个URL，因此要想看到请求头，就具体打印po mutableRequest.allHTTPHeaderFields

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AFURLResponseSerialization.m

- (instancetype)init {
        self = [super init];
        if (!self) {
            return nil;
        }
    
        self.acceptableContentTypes = [NSSet setWithObjects:@"application/json", @"text/json", @"text/javascript", nil];
    
        return self;
    }

通过初始化方法可以看出来，AFNetworking支持的ContentType有：application/json;text/json;text/javascript 。

- (BOOL)validateResponse:(NSHTTPURLResponse *)response
                        data:(NSData *)data
                       error:(NSError * __autoreleasing *)error
    {
        BOOL responseIsValid = YES;
        NSError *validationError = nil;
    
        if (response && [response isKindOfClass:[NSHTTPURLResponse class]]) {
            if (self.acceptableContentTypes && ![self.acceptableContentTypes containsObject:[response MIMEType]] &&
                !([response MIMEType] == nil && [data length] == 0)) {
    
                if ([data length] > 0 && [response URL]) {
                    NSMutableDictionary *mutableUserInfo = [@{
                                                              NSLocalizedDescriptionKey: [NSString stringWithFormat:NSLocalizedStringFromTable(@"Request failed: unacceptable content-type: %@", @"AFNetworking", nil), [response MIMEType]],
                                                              NSURLErrorFailingURLErrorKey:[response URL],
                                                              AFNetworkingOperationFailingURLResponseErrorKey: response,
                                                            } mutableCopy];
                    if (data) {
                        mutableUserInfo[AFNetworkingOperationFailingURLResponseDataErrorKey] = data;
                    }
    
                    validationError = AFErrorWithUnderlyingError([NSError errorWithDomain:AFURLResponseSerializationErrorDomain code:NSURLErrorCannotDecodeContentData userInfo:mutableUserInfo], validationError);
                }
    
                responseIsValid = NO;
            }
    
            if (self.acceptableStatusCodes && ![self.acceptableStatusCodes containsIndex:(NSUInteger)response.statusCode] && [response URL]) {
                NSMutableDictionary *mutableUserInfo = [@{
                                                   NSLocalizedDescriptionKey: [NSString stringWithFormat:NSLocalizedStringFromTable(@"Request failed: %@ (%ld)", @"AFNetworking", nil), [NSHTTPURLResponse localizedStringForStatusCode:response.statusCode], (long)response.statusCode],
                                                   NSURLErrorFailingURLErrorKey:[response URL],
                                                   AFNetworkingOperationFailingURLResponseErrorKey: response,
                                           } mutableCopy];
    
                if (data) {
                    mutableUserInfo[AFNetworkingOperationFailingURLResponseDataErrorKey] = data;
                }
    
                validationError = AFErrorWithUnderlyingError([NSError errorWithDomain:AFURLResponseSerializationErrorDomain code:NSURLErrorBadServerResponse userInfo:mutableUserInfo], validationError);
    
                responseIsValid = NO;
            }
        }
    
        if (error && !responseIsValid) {
            *error = validationError;
        }
    
        return responseIsValid;
    }

通过statusCode==200来判断请求是否成功

查看响应头如下：

[manager POST:urlStr parameters:parameters progress:^(NSProgress * _Nonnull uploadProgress) {
    } success:^(NSURLSessionDataTask * _Nonnull task, id  _Nullable responseObject) {
        NSHTTPURLResponse *response = (NSHTTPURLResponse *)task.response;
        NSDictionary *allHeaders = response.allHeaderFields;
        NSLog(@"响应--%@\n响应头--%@",response,allHeaders);
        
        success(responseObject);
    } failure:^(NSURLSessionDataTask * _Nullable task, NSError * _Nonnull error) {
    }];

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[Center]: https://img-blog.csdn.net/20170810145537741?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvTWluZ2dlUWluZ2NodW4=/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center
[Center 1]: https://img-blog.csdn.net/20170810151918836?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvTWluZ2dlUWluZ2NodW4=/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center