指定したディレクトリ以下の名前がCachesなサブディレクトリにNSURLIsExcludedFromBackupKey属性を設定するスクリプト

setExcludedFromBackupToCaches.swift

#!/usr/bin/env xcrun swift

import Cocoa

extension NSURL {
  var isDirectory: Bool {
    return resourceValue(NSURLIsDirectoryKey)
  }
  var isExcludedFromBackup: Bool {
    return resourceValue(NSURLIsExcludedFromBackupKey)
  }
  func resourceValue(resourceKey: NSString) -> Bool {
    var resourceValue: AnyObject?
    var error: NSError?
    var result = false
    if getResourceValue(&resourceValue, forKey: resourceKey, error: &error) {
      if let number = resourceValue as? NSNumber {
        result = number.boolValue
      } else {
        println("error: \(self) for key: \(resourceKey)")
      }
    } else {
      println("error: \(error?.localizedDescription) on \(self) for key: \(resourceKey)")
    }
    return result
  }
  func setResourceValue(value: NSNumber , forResourceKey resourceKey: NSString) {
    var error: NSError?
    var result = false
    if !setResourceValue(value, forKey: resourceKey, error: &error) {
      println("error: \(error?.localizedDescription) on \(self) for key: \(resourceKey)")
    }
  }
}

func setExcludedFromBackupContentsToCaches(targetURL: NSURL) {
  let keys = [NSURLIsDirectoryKey, NSURLIsExcludedFromBackupKey] as [AnyObject]
  var error: NSError?
  if let contents = NSFileManager.defaultManager().contentsOfDirectoryAtURL(targetURL, includingPropertiesForKeys: keys, options: nil, error: &error) as? [NSURL] {
    for url in contents {
      if url.isDirectory {
        if url.lastPathComponent == "Caches" {
          url.setResourceValue(NSNumber(bool: true), forResourceKey: NSURLIsExcludedFromBackupKey)
          println(url.path!)
        } else {
          setExcludedFromBackupContentsToCaches(url)
        }
      }
    }
  } else {
    println("\(targetURL.path!): \(error!.localizedDescription)")
  }
}

var path = Process.arguments.count > 1 ? Process.arguments[1] : NSFileManager.defaultManager().currentDirectoryPath
if let url = NSURL(fileURLWithPath: path) {
  setExcludedFromBackupContentsToCaches(url)
}

% ./setExcludedFromBackupToCaches.swift ~/Library/Containers

な感じで。