Refactor error handling & reporting in API & Web

Now instead of an Enum, an ErrorType is supplied on each failure.

The ErrorType could be either a OS error (e.g. Foundation errors)
or Auth0 errors either returned by the API or it's components because a
configuration issue.

App/ViewController.swift

@@ -11,7 +11,7 @@ import Auth0
 
 class ViewController: UIViewController {
 
-    var onAuth: (Result<Credentials, Authentication.Error> -> ())!
+    var onAuth: (Result<Credentials> -> ())!
 
     @IBOutlet weak var oauth2: UIButton!
 

Auth0.xcodeproj/project.pbxproj

@@ -95,6 +95,8 @@
 		5FD255AF1D14A4A300387ECB /* AuthenticationError.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5FD255AD1D14A4A300387ECB /* AuthenticationError.swift */; };
 		5FD255B11D14A9E000387ECB /* AuthenticationErrorSpec.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5FD255B01D14A9E000387ECB /* AuthenticationErrorSpec.swift */; };
 		5FD255B21D14A9E000387ECB /* AuthenticationErrorSpec.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5FD255B01D14A9E000387ECB /* AuthenticationErrorSpec.swift */; };
+		5FD255B41D14DD2600387ECB /* ManagementError.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5FD255B31D14DD2600387ECB /* ManagementError.swift */; };
+		5FD255B51D14DD2600387ECB /* ManagementError.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5FD255B31D14DD2600387ECB /* ManagementError.swift */; };
 		5FE2F8A61CCA9C17003628F4 /* CredentialsSpec.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5FE2F8A51CCA9C17003628F4 /* CredentialsSpec.swift */; };
 		5FE2F8A71CCA9C17003628F4 /* CredentialsSpec.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5FE2F8A51CCA9C17003628F4 /* CredentialsSpec.swift */; };
 		5FE2F8A91CCE54F1003628F4 /* Result.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5FE2F8A81CCE54F1003628F4 /* Result.swift */; };
@@ -237,6 +239,7 @@
 		5FCCC31B1CF51DF300901E2E /* _ObjectiveManagementAPI.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = _ObjectiveManagementAPI.swift; sourceTree = "<group>"; };
 		5FD255AD1D14A4A300387ECB /* AuthenticationError.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = AuthenticationError.swift; sourceTree = "<group>"; };
 		5FD255B01D14A9E000387ECB /* AuthenticationErrorSpec.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = AuthenticationErrorSpec.swift; sourceTree = "<group>"; };
+		5FD255B31D14DD2600387ECB /* ManagementError.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = ManagementError.swift; sourceTree = "<group>"; };
 		5FE2F8A51CCA9C17003628F4 /* CredentialsSpec.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = CredentialsSpec.swift; sourceTree = "<group>"; };
 		5FE2F8A81CCE54F1003628F4 /* Result.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Result.swift; sourceTree = "<group>"; };
 		5FE2F8B11CCEAED8003628F4 /* Requestable.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Requestable.swift; sourceTree = "<group>"; };
@@ -558,6 +561,7 @@
 				5FF465BB1CE2AC4500F7ED8C /* Management.swift */,
 				5FADB60B1CED7E0800D4BB50 /* UserPatchAttributes.swift */,
 				5FADB6051CED27FB00D4BB50 /* Users.swift */,
+				5FD255B31D14DD2600387ECB /* ManagementError.swift */,
 			);
 			path = Management;
 			sourceTree = "<group>";
@@ -814,6 +818,7 @@
 				5FCAB1791D09124D00331C84 /* NSURL+Auth0.swift in Sources */,
 				5F7989511CF13A20009E8A10 /* _ObjectiveAuthenticationAPI.swift in Sources */,
 				5F74CB401CEFD5E600226823 /* JSONObjectPayload.swift in Sources */,
+				5FD255B41D14DD2600387ECB /* ManagementError.swift in Sources */,
 				5FE2F8B81CD0E910003628F4 /* Request.swift in Sources */,
 				5FE2F8A91CCE54F1003628F4 /* Result.swift in Sources */,
 				5F3965C21CF67CF000CDE7C0 /* WebAuth.swift in Sources */,
@@ -836,6 +841,7 @@
 				5F6FAC641D09E98000D5B4EA /* Logger.swift in Sources */,
 				5FF465BD1CE2AC4500F7ED8C /* Management.swift in Sources */,
 				5F06DDCA1CC66B710011842B /* Auth0.swift in Sources */,
+				5FD255B51D14DD2600387ECB /* ManagementError.swift in Sources */,
 				5FE2F8B31CCEAED8003628F4 /* Requestable.swift in Sources */,
 				5FCCC31A1CF51BBD00901E2E /* NSError+Management.swift in Sources */,
 				5FE2F8B61CCEB1C0003628F4 /* Handlers.swift in Sources */,

Auth0/Authentication/Authentication.swift

@@ -103,7 +103,7 @@ public struct Authentication {
      - returns: authentication request that will yield Auth0 User Credentials
      - seeAlso: Credentials
      */
-    public func login(username: String, password: String, connection: String, scope: String = "openid", parameters: [String: AnyObject] = [:]) -> Request<Credentials, Error> {
+    public func login(username: String, password: String, connection: String, scope: String = "openid", parameters: [String: AnyObject] = [:]) -> Request<Credentials, AuthenticationError> {
         let resourceOwner = NSURL(string: "/oauth/ro", relativeToURL: self.url)!
         var payload: [String: AnyObject] = [
             "username": username,
@@ -154,7 +154,7 @@ public struct Authentication {
 
      - returns: request that will yield a created database user (just email, username and email verified flag)
      */
-    public func createUser(email: String, username: String? = nil, password: String, connection: String, userMetadata: [String: AnyObject]? = nil) -> Request<DatabaseUser, Error> {
+    public func createUser(email: String, username: String? = nil, password: String, connection: String, userMetadata: [String: AnyObject]? = nil) -> Request<DatabaseUser, AuthenticationError> {
         var payload: [String: AnyObject] = [
             "email": email,
             "password": password,
@@ -188,7 +188,7 @@ public struct Authentication {
 
      - returns: request to reset password
      */
-    public func resetPassword(email: String, connection: String) -> Request<Void, Error> {
+    public func resetPassword(email: String, connection: String) -> Request<Void, AuthenticationError> {
         let payload = [
             "email": email,
             "connection": connection,
@@ -245,9 +245,10 @@ public struct Authentication {
 
      - returns: an authentication request that will yield Auth0 user credentials after creating the user.
      */
-    public func signUp(email: String, username: String? = nil, password: String, connection: String, userMetadata: [String: AnyObject]? = nil, scope: String = "openid", parameters: [String: AnyObject] = [:]) -> ConcatRequest<DatabaseUser, Credentials, Error> {
-        return createUser(email, username: username, password: password, connection: connection, userMetadata: userMetadata)
-            .concat(login(email, password: password, connection: connection, scope: scope, parameters: parameters))
+    public func signUp(email: String, username: String? = nil, password: String, connection: String, userMetadata: [String: AnyObject]? = nil, scope: String = "openid", parameters: [String: AnyObject] = [:]) -> ConcatRequest<DatabaseUser, Credentials, AuthenticationError> {
+        let first = createUser(email, username: username, password: password, connection: connection, userMetadata: userMetadata)
+        let second = login(email, password: password, connection: connection, scope: scope, parameters: parameters)
+        return ConcatRequest(first: first, second: second)
     }
 
     /**
@@ -276,7 +277,7 @@ public struct Authentication {
 
      - returns: a request
      */
-    public func startPasswordless(email email: String, type: PasswordlessType = .Code, connection: String = "email", parameters: [String: AnyObject] = [:]) -> Request<Void, Authentication.Error> {
+    public func startPasswordless(email email: String, type: PasswordlessType = .Code, connection: String = "email", parameters: [String: AnyObject] = [:]) -> Request<Void, AuthenticationError> {
         var payload: [String: AnyObject] = [
             "email": email,
             "connection": connection,
@@ -316,7 +317,7 @@ public struct Authentication {
 
      - returns: a request
      */
-    public func startPasswordless(phoneNumber phoneNumber: String, type: PasswordlessType = .Code, connection: String = "sms") -> Request<Void, Authentication.Error> {
+    public func startPasswordless(phoneNumber phoneNumber: String, type: PasswordlessType = .Code, connection: String = "sms") -> Request<Void, AuthenticationError> {
         let payload: [String: AnyObject] = [
             "phone_number": phoneNumber,
             "connection": connection,
@@ -341,7 +342,7 @@ public struct Authentication {
 
      - returns: a request that will yield token information
      */
-    public func tokenInfo(token: String) -> Request<UserProfile, Authentication.Error> {
+    public func tokenInfo(token: String) -> Request<UserProfile, AuthenticationError> {
         let payload: [String: AnyObject] = ["id_token": token]
         let tokenInfo = NSURL(string: "/tokeninfo", relativeToURL: self.url)!
         return Request(session: session, url: tokenInfo, method: "POST", handle: authenticationObject, payload: payload)
@@ -361,7 +362,7 @@ public struct Authentication {
 
      - returns: a request that will yield user information
      */
-    public func userInfo(token: String) -> Request<UserProfile, Authentication.Error> {
+    public func userInfo(token: String) -> Request<UserProfile, AuthenticationError> {
         let userInfo = NSURL(string: "/userinfo", relativeToURL: self.url)!
         return Request(session: session, url: userInfo, method: "GET", handle: authenticationObject, headers: ["Authorization": "Bearer \(token)"])
     }
@@ -392,7 +393,7 @@ public struct Authentication {
 
      - returns: a request that will yield Auth0 user's credentials
      */
-    public func loginSocial(token: String, connection: String, scope: String = "openid", parameters: [String: AnyObject] = [:]) -> Request<Credentials, Error> {
+    public func loginSocial(token: String, connection: String, scope: String = "openid", parameters: [String: AnyObject] = [:]) -> Request<Credentials, AuthenticationError> {
         var payload: [String: AnyObject] = [
             "access_token": token,
             "connection": connection,
@@ -420,7 +421,7 @@ public struct Authentication {
      - returns: a request that will yield Auth0 user's credentials
      - seeAlso: Authentication#exchangeCode(codeVerifier:redirectURI:) for PKCE
      */
-    public func token(parameters: [String: AnyObject]) -> Request<Credentials, Error> {
+    public func token(parameters: [String: AnyObject]) -> Request<Credentials, AuthenticationError> {
         var payload: [String: AnyObject] = [
             "client_id": self.clientId
         ]
@@ -448,7 +449,7 @@ public struct Authentication {
      - returns: a request that will yield Auth0 user's credentials
      - seeAlso: https://tools.ietf.org/html/rfc7636
      */
-    public func exchangeCode(code: String, codeVerifier: String, redirectURI: String) -> Request<Credentials, Error> {
+    public func exchangeCode(code: String, codeVerifier: String, redirectURI: String) -> Request<Credentials, AuthenticationError> {
         return self.token([
                 "code": code,
                 "code_verifier": codeVerifier,

Auth0/Authentication/AuthenticationError.swift

@@ -22,30 +22,33 @@
 
 import Foundation
 
+let UnknownCode = "a0.internal_error.unknown"
+let NonJSONError = "a0.internal_error.plain"
+let EmptyBodyError = "a0.internal_error.empty"
+
 /**
  *  Represents an error during a request to Auth0 Authentication API
  */
-public struct AuthenticationError: ErrorType, CustomStringConvertible {
+public class AuthenticationError: ResponseError, CustomStringConvertible {
 
-    static let UnknownCode = "a0.internal_error.unknown"
-    static let NonJSONError = "a0.internal_error.plain"
-    static let EmptyBodyError = "a0.internal_error.empty"
+    static let Domain = "com.auth0.authentication"
+    static let UserInfoKey = "com.auth0.authentication.error.info"
 
     /**
      Additional information about the error
      - seeAlso: `code` & `description` properties
      */
     public let info: [String: AnyObject]
 
-    init(string: String? = nil, statusCode: Int = 0) {
-        self.init(info: [
-            "code": string != nil ? AuthenticationError.NonJSONError : AuthenticationError.EmptyBodyError,
+    public required init(string: String? = nil, statusCode: Int = 0) {
+        self.info = [
+            "code": string != nil ? NonJSONError : EmptyBodyError,
             "description": string ?? "Empty response body",
             "statusCode": statusCode
-        ])
+        ]
     }
 
-    init(info: [String: AnyObject]) {
+    public required init(info: [String: AnyObject]) {
         self.info = info
     }
 
@@ -54,7 +57,7 @@ public struct AuthenticationError: ErrorType, CustomStringConvertible {
      */
     public var code: String {
         let code = self.info["error"] ?? self.info["code"]
-        return code as? String ?? AuthenticationError.UnknownCode
+        return code as? String ?? UnknownCode
     }
 
     /**
@@ -67,8 +70,15 @@ public struct AuthenticationError: ErrorType, CustomStringConvertible {
             return string
         }
 
-        guard self.code == AuthenticationError.UnknownCode else { return "Received error with code \(self.code)" }
+        guard self.code == UnknownCode else { return "Received error with code \(self.code)" }
 
         return "Failed with unknown error \(self.info)"
     }
+
+    public var foundationError: NSError {
+        return NSError(domain: AuthenticationError.Domain, code: 1, userInfo: [
+            NSLocalizedDescriptionKey: self.description,
+            AuthenticationError.UserInfoKey: self,
+            ])
+    }
 }

Auth0/Authentication/Handlers.swift

@@ -22,71 +22,39 @@
 
 import Foundation
 
-func authenticationObject<T: JSONObjectPayload>(response: Response, callback: Request<T, Authentication.Error>.Callback) {
-    switch response.result {
-    case .Success(let payload):
-        if let dictionary = payload as? [String: AnyObject], let object = T(json: dictionary) {
+func authenticationObject<T: JSONObjectPayload>(response: Response<AuthenticationError>, callback: Request<T, AuthenticationError>.Callback) {
+    do {
+        if let dictionary = try response.result() as? [String: AnyObject], let object = T(json: dictionary) {
             callback(.Success(result: object))
         } else {
-            callback(.Failure(error: .InvalidResponse(response: response.data)))
+            callback(.Failure(error: AuthenticationError(string: string(response.data))))
         }
-    case .Failure(let cause):
-        callback(.Failure(error: authenticationError(response.data, cause: cause)))
+
+    } catch let error {
+        callback(.Failure(error: error))
     }
 }
 
-func databaseUser(response: Response, callback: Request<DatabaseUser, Authentication.Error>.Callback) {
-    switch response.result {
-    case .Success(let payload):
-        if let dictionary = payload as? [String: AnyObject], let email = dictionary["email"] as? String {
+func databaseUser(response: Response<AuthenticationError>, callback: Request<DatabaseUser, AuthenticationError>.Callback) {
+    do {
+        if let dictionary = try response.result() as? [String: AnyObject], let email = dictionary["email"] as? String {
             let username = dictionary["username"] as? String
             let verified = dictionary["email_verified"] as? Bool ?? false
             callback(.Success(result: (email: email, username: username, verified: verified)))
         } else {
-            callback(.Failure(error: .InvalidResponse(response: response.data)))
+            callback(.Failure(error: AuthenticationError(string: string(response.data))))
         }
-    case .Failure(let cause):
-        callback(.Failure(error: authenticationError(response.data, cause: cause)))
-    }
-}
-
-func noBody(response: Response, callback: Request<Void, Authentication.Error>.Callback) {
-    switch response.result {
-    case .Success:
-        callback(.Success(result: ()))
-    case .Failure(let cause):
-        callback(.Failure(error: authenticationError(response.data, cause: cause)))
-    }
-}
 
-private func authenticationError(data: NSData?, cause: Response.Error) -> Authentication.Error {
-    switch cause {
-    case .InvalidJSON(let data):
-        return .InvalidResponse(response: data)
-    case .ServerError(let status, let data) where (400...500).contains(status) && data != nil:
-        if
-            let json = try? NSJSONSerialization.JSONObjectWithData(data!, options: []),
-            let payload = json as? [String: AnyObject] {
-            return payloadError(payload, cause: cause)
-        } else {
-            return .RequestFailed(cause: cause)
-        }
-    default:
-        return .RequestFailed(cause: cause)
+    } catch let error {
+        callback(.Failure(error: error))
     }
 }
 
-private func payloadError(payload: [String: AnyObject], cause: ErrorType) -> Authentication.Error {
-    if let code = payload["error"] as? String, let description = payload["error_description"] as? String {
-        return .Response(code: code, description: description, name: nil, extras: nil)
-    }
-
-    if let code = payload["code"] as? String, let description = payload["description"] as? String {
-        let name = payload["name"] as? String
-        var extras = payload
-        ["code", "description", "name"].forEach { extras.removeValueForKey($0) }
-        return .Response(code: code, description: description, name: name, extras: extras)
+func noBody(response: Response<AuthenticationError>, callback: Request<Void, AuthenticationError>.Callback) {
+    do {
+        let _ = try response.result()
+        callback(.Success(result: ()))
+    } catch let error {
+        callback(.Failure(error: error))
     }
-
-    return .RequestFailed(cause: cause)
-}
+}