feat: add familiar followers endpoint

Mastodon/Service/APIService/APIService+Recommend.swift

@@ -74,3 +74,36 @@ extension APIService {
     }
 
 }
+
+extension APIService {
+    
+    func familiarFollowers(
+        query: Mastodon.API.Account.FamiliarFollowersQuery,
+        authenticationBox: MastodonAuthenticationBox
+    ) async throws -> Mastodon.Response.Content<[Mastodon.Entity.Account]> {
+        let response = try await Mastodon.API.Account.familiarFollowers(
+            session: session,
+            domain: authenticationBox.domain,
+            query: query,
+            authorization: authenticationBox.userAuthorization
+        ).singleOutput()
+
+//        let managedObjectContext = backgroundManagedObjectContext
+//        try await managedObjectContext.performChanges {
+//            for entity in response.value {
+//                _ = Persistence.MastodonUser.createOrMerge(
+//                    in: managedObjectContext,
+//                    context: Persistence.MastodonUser.PersistContext(
+//                        domain: authenticationBox.domain,
+//                        entity: entity.account,
+//                        cache: nil,
+//                        networkDate: response.networkDate
+//                    )
+//                )
+//            }   // end for … in
+//        }
+
+        return response
+    }
+    
+}

MastodonSDK/Sources/MastodonSDK/API/Mastodon+API+Account+FamiliarFollowers.swift

@@ -0,0 +1,71 @@
+//
+//  Mastodon+API+Account+FamiliarFollowers.swift
+//  
+//
+//  Created by MainasuK on 2022-5-13.
+//
+
+import Foundation
+import Combine
+
+// https://github.com/mastodon/mastodon/pull/17700
+extension Mastodon.API.Account {
+    
+    private static func familiarFollowersEndpointURL(domain: String) -> URL {
+        return Mastodon.API.endpointURL(domain: domain)
+            .appendingPathComponent("accounts")
+            .appendingPathComponent("familiar_followers")
+    }
+    
+    /// Fetch familiar followers
+    ///
+    /// - Since: 3.5.?
+    /// - Version: 3.5.2
+    /// # Last Update
+    ///   2022/5/13
+    /// # Reference
+    ///   [Document](none)
+    /// - Parameters:
+    ///   - session: `URLSession`
+    ///   - domain: Mastodon instance domain. e.g. "example.com"
+    ///   - query: `FamiliarFollowersQuery`
+    ///   - authorization: User token
+    /// - Returns: `AnyPublisher` contains `[Mastodon.Entity.Account]` nested in the response
+    public static func familiarFollowers(
+        session: URLSession,
+        domain: String,
+        query: FamiliarFollowersQuery,
+        authorization: Mastodon.API.OAuth.Authorization
+    ) -> AnyPublisher<Mastodon.Response.Content<[Mastodon.Entity.Account]>, Error> {
+        let request = Mastodon.API.get(
+            url: familiarFollowersEndpointURL(domain: domain),
+            query: query,
+            authorization: authorization
+        )
+        return session.dataTaskPublisher(for: request)
+            .tryMap { data, response in
+                let value = try Mastodon.API.decode(type: [Mastodon.Entity.Account].self, from: data, response: response)
+                return Mastodon.Response.Content(value: value, response: response)
+            }
+            .eraseToAnyPublisher()
+    }
+    
+    public struct FamiliarFollowersQuery: GetQuery {
+        public let accounts: [Mastodon.Entity.Account.ID]
+        
+        public init(accounts: [Mastodon.Entity.Account.ID]) {
+            self.accounts = accounts
+        }
+        
+        var queryItems: [URLQueryItem]? {
+            var items: [URLQueryItem] = []
+            let accountsValue = accounts.joined(separator: ",")
+            if !accountsValue.isEmpty {
+                items.append(URLQueryItem(name: "accounts", value: accountsValue))
+            }
+            guard !items.isEmpty else { return nil }
+            return items
+        }
+    }
+    
+}