Add resume feature

Sources/CapTrain.swift

@@ -4,6 +4,9 @@ import Foundation
 @main
 struct CapTrain: AsyncParsableCommand {
     
+    @Flag(name: .shortAndLong, help: "Resume the previous training session (default: false)")
+    var resume: Bool = false
+    
     @Argument(help: "The path to the configuration file")
     var configPath: String?
     
@@ -35,7 +38,7 @@ struct CapTrain: AsyncParsableCommand {
             serverPath: serverPath,
             authenticationToken: authenticationToken)
         
-        let creator = try ClassifierCreator(configuration: configuration)
+        let creator = try ClassifierCreator(configuration: configuration, resume: resume)
         try await creator.run()
     }
     

Sources/ClassifierCreator.swift

@@ -29,7 +29,7 @@ final class ClassifierCreator {
     
     // MARK: Step 1: Load configuration
     
-    init(configuration: Configuration) throws {
+    init(configuration: Configuration, resume: Bool) throws {
         self.configuration = configuration
         self.server = try configuration.serverUrl()
         let contentDirectory = URL(fileURLWithPath: configuration.contentFolder)
@@ -38,6 +38,21 @@ final class ClassifierCreator {
         self.classifierUrl = contentDirectory.appendingPathComponent("classifier.mlmodel")
         self.thumbnailDirectory = contentDirectory.appendingPathComponent("thumbnails")
         df.dateFormat = "yy-MM-dd-HH-mm-ss"
+        if !resume {
+            try removeSessionData()
+        }
+    }
+    
+    private func removeSessionData() throws {
+        guard FileManager.default.fileExists(atPath: sessionDirectory.path) else {
+            return
+        }
+        do {
+            try FileManager.default.removeItem(at: sessionDirectory)
+            print(info: "Removed training session data")
+        } catch {
+            throw TrainingError.failedToRemoveSessionFolder(error)
+        }
     }
     
     // MARK: Main function
@@ -71,6 +86,7 @@ final class ClassifierCreator {
         try await uploadModel(version: newVersion)
         try await upload(classes: classes, lastUpdate: imagesSnapshotDate)
         try await createThumbnails(changed: changedMainImages)
+        try removeSessionData()
         print(info: "Done")
     }
     

Sources/TrainingError.swift

@@ -11,6 +11,7 @@ enum TrainingError: Error {
     case configurationFileDecodingFailed(URL, Error)
     case invalidServerPath(String)
     case mainImageFolderNotCreated(Error)
+    case failedToRemoveSessionFolder(Error)
     
     case failedToGetCapDatabase(Error)
     case failedToDecodeCapDatabase(Error)
@@ -65,6 +66,8 @@ extension TrainingError: CustomStringConvertible {
             return "Configuration: Invalid server path \(path)"
         case .mainImageFolderNotCreated(let error):
             return "Failed to create main image folder: \(error)"
+        case .failedToRemoveSessionFolder(let error):
+            return "Failed to remove session folder: \(error)"
             
         case .failedToGetCapDatabase(let error):
             return "Failed to get cap database from server: \(error)"