add more comments and a missing shouldOverwrite property

IceCream/Classes/CreamAsset.swift

@@ -28,27 +28,30 @@ public class CreamAsset: Object {
  self.uniqueFileName = "\(objectID)_\(propName)"
  }
 
- /// There is an important point that we need to consider:
- /// Cuz we only store the path of data, so we can't access data by `data` property
- /// So use this method if you want get the data of this object
+ /// Use this method to fetch the underlying data of the CreamAsset
  public func storedData() -> Data? {
  return try? Data(contentsOf: filePath)
  }
 
+ /// Where the asset locates in the file system
  public var filePath: URL {
  return CreamAsset.creamAssetDefaultURL().appendingPathComponent(uniqueFileName)
  }
 
- private static func save(data: Data, to path: String, shouldOverwrite: Bool) {
+ /// Save the given data to local file system
+ /// - Parameters:
+ /// - data: The data to save
+ /// - path:
+ /// - shouldOverwrite: Whether should overwrite current file existed at path or not.
+ private static func save(data: Data, to path: String, shouldOverwrite: Bool) throws {
  let url = CreamAsset.creamAssetDefaultURL().appendingPathComponent(path)
  guard shouldOverwrite || !FileManager.default.fileExists(atPath: url.path) else { return }
- do {
- try data.write(to: url)
- } catch {
- /// Os.log output data infos here
- }
+ try data.write(to: url)
  }
 
+ // MARK: - CKRecordConvertible & CKRecordRecoverable
+
+ /// Wrap asset as CKAsset for uploading to CloudKit
  var asset: CKAsset {
  get {
  return CKAsset(fileURL: filePath)
@@ -69,19 +72,7 @@ public class CreamAsset: Object {
  url: url)
  }
 
- /// Creates a new CreamAsset for the given object with Data
- ///
- /// - Parameters:
- /// - object: The object the asset will live on
- /// - propName: The unique property name to identify this asset. e.g.: Dog Object may have multiple CreamAsset properties, so we need unique `propName`s to identify these.
- /// - data: The file data
- /// - shouldOverwrite: Whether to try and save the file even if an existing file exists for the same object.
- /// - Returns: A CreamAsset if it was successful
- public static func create(object: CKRecordConvertible, propName: String, data: Data, shouldOverwrite: Bool = true) -> CreamAsset? {
- return create(objectID: object.recordID.recordName,
- propName: propName,
- data: data)
- }
+ // MARK: - Factory methods
 
  /// Creates a new CreamAsset for the given object id with Data
  ///
@@ -94,8 +85,28 @@ public class CreamAsset: Object {
  public static func create(objectID: String, propName: String, data: Data, shouldOverwrite: Bool = true) -> CreamAsset? {
  let creamAsset = CreamAsset(objectID: objectID,
  propName: propName)
- save(data: data, to: creamAsset.uniqueFileName, shouldOverwrite: shouldOverwrite)
- return creamAsset
+ do {
+ save(data: data, to: creamAsset.uniqueFileName, shouldOverwrite: shouldOverwrite)
+ return creamAsset
+ } catch {
+ // Os.log error here
+ return nil
+ }
+ }
+
+ /// Creates a new CreamAsset for the given object with Data
+ ///
+ /// - Parameters:
+ /// - object: The object the asset will live on
+ /// - propName: The unique property name to identify this asset. e.g.: Dog Object may have multiple CreamAsset properties, so we need unique `propName`s to identify these.
+ /// - data: The file data
+ /// - shouldOverwrite: Whether to try and save the file even if an existing file exists for the same object.
+ /// - Returns: A CreamAsset if it was successful
+ public static func create(object: CKRecordConvertible, propName: String, data: Data, shouldOverwrite: Bool = true) -> CreamAsset? {
+ return create(objectID: object.recordID.recordName,
+ propName: propName,
+ data: data,
+ shouldOverwrite: shouldOverwrite)
  }
 
  /// Creates a new CreamAsset for the given object with a URL
@@ -118,13 +129,13 @@ public class CreamAsset: Object {
  /// - propName: The unique property name to identify this asset. e.g.: Dog Object may have multiple CreamAsset properties, so we need unique `propName`s to identify these.
  /// - url: The location where asset locates
  /// - Returns: The CreamAsset if creates successful
- public static func create(objectID: String, propName: String, url: URL) -> CreamAsset? {
+ static func create(objectID: String, propName: String, url: URL) -> CreamAsset? {
  let creamAsset = CreamAsset(objectID: objectID, propName: propName)
  if !FileManager.default.fileExists(atPath: creamAsset.filePath.path) {
  do {
  try FileManager.default.copyItem(at: url, to: creamAsset.filePath)
  } catch {
- /// Log: copy item failed
+ /// Os.log copy item failed
  return nil
  }
  }