Different path URL for FileManager everytime I open the app-CodePudding

I want to create one folder in the fileManager root path, but before creating it, I want to check that the folder exist or not, and if not, I will create, otherwise will leave it

here are the function that I use

public func isDirectoryExist(path: String) -> Bool {
    let fileManager = FileManager.default
    var isDir : ObjCBool = false
    if fileManager.fileExists(atPath: path, isDirectory:&isDir) {
        if isDir.boolValue {
            return true
        } else {
            return false
        }
    } else {
        return false
    }
}


public func createNewDirectory(name: String) {
    
    let DocumentDirectory = NSURL(fileURLWithPath: NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0])
    let DirPath = DocumentDirectory.appendingPathComponent(name)
    do
    {
        try FileManager.default.createDirectory(atPath: DirPath!.path, withIntermediateDirectories: true, attributes: nil)
    }
    catch let error as NSError
    {
        Logger.logError("Unable to create directory \(error.debugDescription)")
    }
    Logger.logInfo("Dir Path = \(DirPath!)")
}

Now, when I check the folder existing, it's always false and create a new folder and it happen every time

    func createARObjectDirectory() {
        let rootURL = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0]
        if isDirectoryExist(path: "\(rootURL.absoluteString)\(DefaultURL.arObjectUrlDirectoryName)") {
            Logger.logServer("ARObject directly found")
        } else {
            createNewDirectory(name: DefaultURL.arObjectUrlDirectoryName)
        }
    }

Then I print the root url, and seems the hash in the middle of url is always different, how I can check it?

 file:///var/mobile/Containers/Data/Application/5AD0690B-498D-4309-8BD0-191FB88766AC/Documents/AR-Object/
 file:///var/mobile/Containers/Data/Application/41D35A54-1807-417E-AE29-311D43FCC21D/Documents/AR-Object/
 file:///var/mobile/Containers/Data/Application/F7E385CC-7921-4C37-B9BF-BCEFFC2AEE9E/Documents/AR-Object/
 file:///var/mobile/Containers/Data/Application/4748B014-5E55-46BB-BC83-394A6BC27292/Documents/AR-Object/

Thanks for your help

CodePudding user response：

You are using the wrong API. absoluteString (in rootURL.absoluteString) returns the string representation including the scheme file://. The correct API for file system URLs is path

I recommend to use the URL related API as much as possible

public func directoryExists(at url: URL) -> Bool {
    let fileManager = FileManager.default
    var isDir : ObjCBool = false
    if fileManager.fileExists(atPath: url.path, isDirectory:&isDir) {
        return isDir.boolValue
    } else {
        return false
    }
}

and compose the URL in a more reliable way

func createARObjectDirectory() {
    let rootURL = try! FileManager.default.url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: false)
    if directoryExists(at: rootURL.appendingPathComponent(DefaultURL.arObjectUrlDirectoryName)  {
        Logger.logServer("ARObject directly found")
    } else {
        createNewDirectory(name: DefaultURL.arObjectUrlDirectoryName)
    }
}

And this is swiftier too

public func createNewDirectory(name: String) {
    
    let documentDirectory = try! FileManager.default.url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: false)
    let dirURL = documentDirectory.appendingPathComponent(name)
    do
    {
        try FileManager.default.createDirectory(at: dirURL, withIntermediateDirectories: false, attributes: nil)
    }
    catch let error as NSError
    {
        Logger.logError("Unable to create directory \(error.debugDescription)")
    }
    Logger.logInfo("Dir Path = \(dirPath.path)")
}

CodePudding user response：

The actual path to your app's documents directory is subject to change. You should use relative paths from the documents directory, and not try to compare paths between runs.

(I believe the path changes each time you rebuild your app or reinstall it, but is {fairly} stable for app store builds.)

Are you saying that the directory you create inside the documents directory goes away between runs? That should not be true. The contents of the documents directory should persist.