这个问题已经有很多优秀而广泛的答案，但我觉得我必须提一下，因为没有人提过。

斯威夫特的Alamofire。https://github.com/Alamofire/Alamofire

它是由与AFNetworking相同的人创建的，但在设计时更直接地考虑了Swift。

我们根据具体情况使用几种方法。对于大多数事情来说，AFNetworking是最简单和最健壮的方法，因为你可以设置标题，上传多部分数据，使用GET, POST, PUT和DELETE，还有一堆附加的UIKit类别，允许你从url设置图像。在一个有很多调用的复杂应用程序中，我们有时会将其抽象为我们自己的方便方法，就像这样:

-(void)makeRequestToUrl:(NSURL *)url withParameters:(NSDictionary *)parameters success:(void (^)(id responseObject))success failure:(void (^)(AFHTTPRequestOperation *operation, NSError *error))failure;

有一些情况下，AFNetworking是不合适的，但是，如你正在创建一个框架或其他库组件，因为AFNetworking可能已经在另一个代码库。在这种情况下，你可以使用NSMutableURLRequest内联，如果你正在做一个单独的调用或抽象到一个请求/响应类。

从纯类设计的角度来看，你通常会有这样的东西:

Your view controllers controlling one or more views Data model class - It really depends upon how many real distinct entities you are dealing with, and how they are related. For example, if you have an array of items to be displayed in four different representations (list, chart, graph etc), you will have one data model class for list of items, one more for an item. The list of item class will be shared by four view controllers - all children of a tab bar controller or a nav controller. Data model classes will come handy in not only displaying data, but also serializing them wherein each of them can expose their own serialization format through JSON / XML / CSV (or anything else) export methods. It is important to understand that you also need API request builder classes that map directly with your REST API endpoints. Let's say you have an API that logs the user in - so your Login API builder class will create POST JSON payload for login api. In another example, an API request builder class for list of catalog items API will create GET query string for corresponding api and fire the REST GET query. These API request builder classes will usually receive data from view controllers and also pass the same data back to view controllers for UI update / other operations. View controllers will then decide how to update Data Model objects with that data. Finally, the heart of the REST client - API data fetcher class which is oblivious to all sorts of API requests your app makes. This class will more likely be a singleton, but as others pointed out, it doesn't have to be a singleton. Note that the link is just a typical implementation and does not take into consideration scenarios like session, cookies etc, but it is enough to get you going without using any 3rd party frameworks.

试试https://github.com/kevin0571/STNetTaskQueue

在分开的类中创建API请求。

STNetTaskQueue将处理线程和委托/回调。

可针对不同协议进行扩展。

在移动软件工程中，应用最广泛的是Clean Architecture + MVVM和Redux模式。

Clean Architecture + MVVM由3层组成: 域、表示、数据层。 表示层和数据存储库层依赖于域层:

Presentation Layer -> Domain Layer <- Data Repositories Layer

表示层由视图模型和视图(MVVM)组成:

Presentation Layer (MVVM) = ViewModels + Views
Domain Layer = Entities + Use Cases + Repositories Interfaces
Data Repositories Layer = Repositories Implementations + API (Network) + Persistence DB

在本文中，将对Clean Architecture + MVVM进行更详细的描述 https://tech.olx.com/clean-architecture-and-mvvm-on-ios-c9d167d9f5b3

在我的情况下，我通常使用ResKit库来设置网络层。它提供了易于使用的解析。它减少了我为不同的响应设置映射的工作量。

我只添加了一些代码来自动设置映射。 我为我的模型定义了基类(不是协议，因为有很多代码来检查一些方法是否被实现，模型本身的代码更少):

MappableEntry。h

@interface MappableEntity : NSObject

+ (NSArray*)pathPatterns;
+ (NSArray*)keyPathes;
+ (NSArray*)fieldsArrayForMapping;
+ (NSDictionary*)fieldsDictionaryForMapping;
+ (NSArray*)relationships;

@end

MappableEntry米。

@implementation MappableEntity

+(NSArray*)pathPatterns {
    return @[];
}

+(NSArray*)keyPathes {
    return nil;
}

+(NSArray*)fieldsArrayForMapping {
    return @[];
}

+(NSDictionary*)fieldsDictionaryForMapping {
    return @{};
}

+(NSArray*)relationships {
    return @[];
}

@end

关系是表示响应中嵌套对象的对象:

RelationshipObject.h

@interface RelationshipObject : NSObject

@property (nonatomic,copy) NSString* source;
@property (nonatomic,copy) NSString* destination;
@property (nonatomic) Class mappingClass;

+(RelationshipObject*)relationshipWithKey:(NSString*)key andMappingClass:(Class)mappingClass;
+(RelationshipObject*)relationshipWithSource:(NSString*)source destination:(NSString*)destination andMappingClass:(Class)mappingClass;

@end

RelationshipObject.m

@implementation RelationshipObject

+(RelationshipObject*)relationshipWithKey:(NSString*)key andMappingClass:(Class)mappingClass {
    RelationshipObject* object = [[RelationshipObject alloc] init];
    object.source = key;
    object.destination = key;
    object.mappingClass = mappingClass;
    return object;
}

+(RelationshipObject*)relationshipWithSource:(NSString*)source destination:(NSString*)destination andMappingClass:(Class)mappingClass {
    RelationshipObject* object = [[RelationshipObject alloc] init];
    object.source = source;
    object.destination = destination;
    object.mappingClass = mappingClass;
    return object;
}

@end

然后我像这样为RestKit设置映射:

ObjectMappingInitializer.h

@interface ObjectMappingInitializer : NSObject

+(void)initializeRKObjectManagerMapping:(RKObjectManager*)objectManager;

@end

ObjectMappingInitializer.m

@interface ObjectMappingInitializer (Private)

+ (NSArray*)mappableClasses;

@end

@implementation ObjectMappingInitializer

+(void)initializeRKObjectManagerMapping:(RKObjectManager*)objectManager {

    NSMutableDictionary *mappingObjects = [NSMutableDictionary dictionary];

    // Creating mappings for classes
    for (Class mappableClass in [self mappableClasses]) {
        RKObjectMapping *newMapping = [RKObjectMapping mappingForClass:mappableClass];
        [newMapping addAttributeMappingsFromArray:[mappableClass fieldsArrayForMapping]];
        [newMapping addAttributeMappingsFromDictionary:[mappableClass fieldsDictionaryForMapping]];
        [mappingObjects setObject:newMapping forKey:[mappableClass description]];
    }

    // Creating relations for mappings
    for (Class mappableClass in [self mappableClasses]) {
        RKObjectMapping *mapping = [mappingObjects objectForKey:[mappableClass description]];
        for (RelationshipObject *relation in [mappableClass relationships]) {
            [mapping addPropertyMapping:[RKRelationshipMapping relationshipMappingFromKeyPath:relation.source toKeyPath:relation.destination withMapping:[mappingObjects objectForKey:[relation.mappingClass description]]]];
        }
    }

    // Creating response descriptors with mappings
    for (Class mappableClass in [self mappableClasses]) {
        for (NSString* pathPattern in [mappableClass pathPatterns]) {
            if ([mappableClass keyPathes]) {
                for (NSString* keyPath in [mappableClass keyPathes]) {
                    [objectManager addResponseDescriptor:[RKResponseDescriptor responseDescriptorWithMapping:[mappingObjects objectForKey:[mappableClass description]] method:RKRequestMethodAny pathPattern:pathPattern keyPath:keyPath statusCodes:RKStatusCodeIndexSetForClass(RKStatusCodeClassSuccessful)]];
                }
            } else {
                [objectManager addResponseDescriptor:[RKResponseDescriptor responseDescriptorWithMapping:[mappingObjects objectForKey:[mappableClass description]] method:RKRequestMethodAny pathPattern:pathPattern keyPath:nil statusCodes:RKStatusCodeIndexSetForClass(RKStatusCodeClassSuccessful)]];
            }
        }
    }

    // Error Mapping
    RKObjectMapping *errorMapping = [RKObjectMapping mappingForClass:[Error class]];
    [errorMapping addAttributeMappingsFromArray:[Error fieldsArrayForMapping]];
    for (NSString *pathPattern in Error.pathPatterns) {
        [[RKObjectManager sharedManager] addResponseDescriptor:[RKResponseDescriptor responseDescriptorWithMapping:errorMapping method:RKRequestMethodAny pathPattern:pathPattern keyPath:nil statusCodes:RKStatusCodeIndexSetForClass(RKStatusCodeClassClientError)]];
    }
}

@end

@implementation ObjectMappingInitializer (Private)

+ (NSArray*)mappableClasses {
    return @[
        [FruiosPaginationResults class],
        [FruioItem class],
        [Pagination class],
        [ContactInfo class],
        [Credentials class],
        [User class]
    ];
}

@end

MappableEntry实现的一些例子:

User.h

@interface User : MappableEntity

@property (nonatomic) long userId;
@property (nonatomic, copy) NSString *username;
@property (nonatomic, copy) NSString *email;
@property (nonatomic, copy) NSString *password;
@property (nonatomic, copy) NSString *token;

- (instancetype)initWithUsername:(NSString*)username email:(NSString*)email password:(NSString*)password;

- (NSDictionary*)registrationData;

@end

User.m

@implementation User

- (instancetype)initWithUsername:(NSString*)username email:(NSString*)email password:(NSString*)password {
    if (self = [super init]) {
        self.username = username;
        self.email = email;
        self.password = password;
    }
    return self;
}

- (NSDictionary*)registrationData {
    return @{
        @"username": self.username,
        @"email": self.email,
        @"password": self.password
    };
}

+ (NSArray*)pathPatterns {
    return @[
        [NSString stringWithFormat:@"/api/%@/users/register", APIVersionString],
        [NSString stringWithFormat:@"/api/%@/users/login", APIVersionString]
    ];
}

+ (NSArray*)fieldsArrayForMapping {
    return @[ @"username", @"email", @"password", @"token" ];
}

+ (NSDictionary*)fieldsDictionaryForMapping {
    return @{ @"id": @"userId" };
}

@end

---

现在关于请求包装:

我有头文件与块定义，以减少行长度在所有APIRequest类:

APICallbacks.h

typedef void(^SuccessCallback)();
typedef void(^SuccessCallbackWithObjects)(NSArray *objects);
typedef void(^ErrorCallback)(NSError *error);
typedef void(^ProgressBlock)(float progress);

我的APIRequest类的例子，我正在使用:

LoginAPI。h

@interface LoginAPI : NSObject

- (void)loginWithCredentials:(Credentials*)credentials onSuccess:(SuccessCallbackWithObjects)onSuccess onError:(ErrorCallback)onError;

@end

公元LoginAPI。

@implementation LoginAPI

- (void)loginWithCredentials:(Credentials*)credentials onSuccess:(SuccessCallbackWithObjects)onSuccess onError:(ErrorCallback)onError {
    [[RKObjectManager sharedManager] postObject:nil path:[NSString stringWithFormat:@"/api/%@/users/login", APIVersionString] parameters:[credentials credentialsData] success:^(RKObjectRequestOperation *operation, RKMappingResult *mappingResult) {
        onSuccess(mappingResult.array);
    } failure:^(RKObjectRequestOperation *operation, NSError *error) {
        onError(error);
    }];
}

@end

在代码中，你只需要初始化API对象，并在需要时调用它:

SomeViewController。m

@implementation SomeViewController {
    LoginAPI *_loginAPI;
    // ...
}

- (void)viewDidLoad {
    [super viewDidLoad];

    _loginAPI = [[LoginAPI alloc] init];
    // ...
}

// ...

- (IBAction)signIn:(id)sender {
    [_loginAPI loginWithCredentials:_credentials onSuccess:^(NSArray *objects) {
        // Success Block
    } onError:^(NSError *error) {
        // Error Block
    }];
}

// ...

@end

我的代码并不完美，但很容易设置一次，并用于不同的项目。如果任何人都感兴趣，我可以花一些时间，在GitHub和CocoaPods上为它做一个通用的解决方案。