身份验证

身份验证变化多样。可以通过一些方法对网络请求进行身份验证。让我们来讨论常见的两种。

基本的HTTP身份验证

HTTP身份验证是一个 username/password HTTP协议内置的验证方式. 如果您需要使用 HTTP身份验证, 当初始化provider的时候可以使用一个 CredentialsPlugin 。

swift

let provider = MoyaProvider<YourAPI>(plugins: [CredentialsPlugin { _ -> URLCredential? in
        URLCredential(user: "user", password: "passwd", persistence: .none)
    }
])

这个特定的例子显示了HTTP的使用，它验证每个请求, 通常这是不必要的。下面的方式可能更好:

swift

let provider = MoyaProvider<YourAPI>(plugins: [CredentialsPlugin { target -> URLCredential? in
        switch target {
        case .targetThatNeedsAuthentication:
            return URLCredential(user: "user", password: "passwd", persistence: .none)
        default:
            return nil
        }
    }
])

访问令牌认证

另一个常见的身份验证方法就是通过使用一个访问令牌。 Moya提供一个 AccessTokenPlugin 来完成 JWT的 Bearer 认证和 Basic 认证。

开始使用AccessTokenPlugin之前需要两个步骤.

您需要把 AccessTokenPlugin 添加到您的MoyaProvider中，就像下面这样:

Swift

let token = "eyeAm.AJsoN.weBTOKen"
let authPlugin = AccessTokenPlugin { _ in token }
let provider = MoyaProvider<YourAPI>(plugins: [authPlugin])

如果你使用 MultiTarget 且返回不同的令牌，你可以像下面这样:

swift

let fooToken = "eyeAm.AJsoN.weBTOKen.foo"
let barToken = "eyeAm.AJsoN.weBTOKen.bar"
let authPlugin = AccessTokenPlugin { target in 
    if target is FooService {
        return fooToken    
    } else if target is BarService {
        return barToken
    }
    return ""
}
let provider = MoyaProvider<MultiTarget>(plugins: [authPlugin])

AccessTokenPlugin 构造器接收一个tokenClosure闭包来负责返回一个可以被添加到request头部的令牌。

您的 TargetType 需要遵循AccessTokenAuthorizable 协议:

Swift

extension YourAPI: TargetType, AccessTokenAuthorizable {
    case targetThatNeedsBearerAuth
    case targetThatNeedsBasicAuth
    case targetThatNeedsCustomAuth
    case targetDoesNotNeedAuth

    var authorizationType: AuthorizationType? {
        switch self {
            case .targetThatNeedsBearerAuth:
                return .bearer
            case .targetThatNeedsBasicAuth:
                return .basic
            case .targetThatNeedsCustomAuth:
                return .custom("CustomAuthorizationType")
            case .targetDoesNotNeedAuth:
                return nil
        }
}

AccessTokenAuthorizable 协议需要您实现一个属性 , authorizationType, 是一个枚举值，代表用于请求的头

Bearer HTTP 认证 Bearer 请求通过向HTTP头部添加下面的表单来获得授权:

Authorization: Bearer <token>

Basic API Key 认证 Basic 请求通过向HTTP头部添加下面的表单来获得授权

Authorization: Basic <token>

OAuth

OAuth 有些麻烦。它涉及一个多步骤的过程，在不同的api之间通常是不同的。您确实不想自己来做OAuth – 这儿有其他的库为您服务. Heimdallr.swift, 例如. The trick is just getting Moya and whatever you're using to talk to one another.

Moya内置了OAuth思想。使用OAuth的网络请求“签名”本身有时会要求执行网络请求，所以对Moya的请求是一个异步的过程。让我们看看一个例子。

swift

let requestClosure = { (endpoint: Endpoint, done: MoyaProvider.RequestResultClosure) in
    let request = endpoint.urlRequest // This is the request Moya generates
    YourAwesomeOAuthProvider.signRequest(request, completion: { signedRequest in
        // The OAuth provider can make its own network calls to sign your request.
        // However, you *must* call `done()` with the signed so that Moya can
        // actually send it!
        done(.success(signedRequest))
    })
}
let provider = MoyaProvider<YourAPI>(requestClosure: requestClosure)

(注意 Swift能推断出您的 YourAPI 类型)

在您的Provider子类中处理session刷新

您可以查看在每个请求前session刷新的示例Examples/SubclassingProvider. 它是基于 Artsy's networking implementation.