Implement file size limit

SignalServiceKit/src/Loki/API/LokiAPI.swift

@@ -136,7 +136,7 @@ public final class LokiAPI : NSObject {
                     getDestinations()
                     lastDeviceLinkUpdate[hexEncodedPublicKey] = Date()
                 }.catch(on: DispatchQueue.global()) { error in
-                    if case LokiDotNetAPI.Error.parsingFailed = error {
+                    if (error as? LokiDotNetAPI.Error) == LokiDotNetAPI.Error.parsingFailed {
                         // Don't immediately re-fetch in case of failure due to a parsing error
                         lastDeviceLinkUpdate[hexEncodedPublicKey] = Date()
                         getDestinations()

SignalServiceKit/src/Loki/API/LokiDotNetAPI.swift

@@ -12,8 +12,14 @@ public class LokiDotNetAPI : NSObject {
     private static let attachmentType = "network.loki"
     
     // MARK: Error
-    public enum Error : Swift.Error {
-        case generic, parsingFailed, encryptionFailed, decryptionFailed, signingFailed
+    @objc public class Error : NSError {
+        
+        @objc public static let generic = Error(domain: "com.loki-project.loki-messenger", code: 1, userInfo: [ NSLocalizedDescriptionKey : "An error occurred." ])
+        @objc public static let parsingFailed = Error(domain: "com.loki-project.loki-messenger", code: 2, userInfo: [ NSLocalizedDescriptionKey : "Invalid file server response." ])
+        @objc public static let signingFailed = Error(domain: "com.loki-project.loki-messenger", code: 3, userInfo: [ NSLocalizedDescriptionKey : "Couldn't sign message." ])
+        @objc public static let encryptionFailed = Error(domain: "com.loki-project.loki-messenger", code: 4, userInfo: [ NSLocalizedDescriptionKey : "Couldn't encrypt file." ])
+        @objc public static let decryptionFailed = Error(domain: "com.loki-project.loki-messenger", code: 5, userInfo: [ NSLocalizedDescriptionKey : "Couldn't decrypt file." ])
+        @objc public static let maxFileSizeExceeded = Error(domain: "com.loki-project.loki-messenger", code: 6, userInfo: [ NSLocalizedDescriptionKey : "Maximum file size exceeded." ])
     }
 
     // MARK: Database
@@ -62,6 +68,11 @@ public class LokiDotNetAPI : NSObject {
                 } else {
                     data = unencryptedAttachmentData
                 }
+                // Check the file size if needed
+                let isLokiFileServer = (server == LokiFileServerAPI.server)
+                if isLokiFileServer && data.count > LokiFileServerAPI.maxFileSize {
+                    return seal.reject(Error.maxFileSizeExceeded)
+                }
                 // Create the request
                 let url = "\(server)/files"
                 let parameters: JSON = [ "type" : attachmentType, "Content-Type" : "application/binary" ]

SignalServiceKit/src/Loki/API/LokiFileServerAPI.swift

@@ -9,6 +9,7 @@ public final class LokiFileServerAPI : LokiDotNetAPI {
     #else
     @objc public static let server = "https://file.getsession.org"
     #endif
+    public static let maxFileSize = 10_000_000 // 10 MB
     private static let deviceLinkType = "network.loki.messenger.devicemapping"
     private static let attachmentType = "net.app.core.oembed"
 

SignalServiceKit/src/Loki/API/Public Chat/LokiPublicChatPoller.swift

@@ -198,7 +198,7 @@ public final class LokiPublicChatPoller : NSObject {
                             LokiAPI.lastDeviceLinkUpdate[$0] = Date()
                         }
                     }.catch(on: DispatchQueue.global()) { error in
-                        if case LokiDotNetAPI.Error.parsingFailed = error {
+                        if (error as? LokiDotNetAPI.Error) == LokiDotNetAPI.Error.parsingFailed {
                             // Don't immediately re-fetch in case of failure due to a parsing error
                             hexEncodedPublicKeysToUpdate.forEach {
                                 LokiAPI.lastDeviceLinkUpdate[$0] = Date()