Merge pull request #340 from zacwest/fix-login into /develop

Handle onboarding authentication errors in /api/v1/instance

MastodonSDK/Sources/MastodonSDK/API/Mastodon+API+Instance.swift

@@ -37,7 +37,18 @@ extension Mastodon.API.Instance {
         )
         return session.dataTaskPublisher(for: request)
             .tryMap { data, response in
-                let value = try Mastodon.API.decode(type: Mastodon.Entity.Instance.self, from: data, response: response)
+                let value: Mastodon.Entity.Instance
+
+                do {
+                    value = try Mastodon.API.decode(type: Mastodon.Entity.Instance.self, from: data, response: response)
+                } catch {
+                    if let response = response as? HTTPURLResponse, 400 ..< 500 ~= response.statusCode {
+                        // For example, AUTHORIZED_FETCH may result in authentication errors
+                        value = Mastodon.Entity.Instance(domain: domain)
+                    } else {
+                        throw error
+                    }
+                }
                 return Mastodon.Response.Content(value: value, response: response)
             }
             .eraseToAnyPublisher()

MastodonSDK/Sources/MastodonSDK/Entity/Mastodon+Entity+Instance.swift

@@ -38,6 +38,25 @@ extension Mastodon.Entity {
         // https://github.com/mastodon/mastodon/pull/16485
         public let configuration: Configuration?
 
+        public init(domain: String) {
+            self.uri = domain
+            self.title = domain
+            self.description = ""
+            self.shortDescription = nil
+            self.email = ""
+            self.version = nil
+            self.languages = nil
+            self.registrations = nil
+            self.approvalRequired = nil
+            self.invitesEnabled = nil
+            self.urls = nil
+            self.statistics = nil
+            self.thumbnail = nil
+            self.contactAccount = nil
+            self.rules = nil
+            self.configuration = nil
+        }
+
         enum CodingKeys: String, CodingKey {
             case uri
             case title