SwiftUI | File found on simulator but not on iOS device - ios

Question

I'm trying to create a connection between my program and a database located in /Documents of the app. When the code is built using on the simulator, it successfully opens the database; however, when I run the code on an iOS device, it can't find the file.
This is the code that I use:
let path = NSSearchPathForDirectoriesInDomains(
.documentDirectory, .userDomainMask, true
).first!
let db = try! Connection("\(path)/Database.db")
These are the contents of the variable path when I run the code on the simulator:
/Users/xxxx/Library/Developer/CoreSimulator/Devices/EFD14A1B-7207-4840-9ACE-8E44A269CC70/data/Containers/Data/Application/58D150B9-E242-4857-B06C-DA28C88A26D0/Documents
And these are the contents of the variable path when I run the code on an iOS device:
/var/mobile/Containers/Data/Application/4EC93D76-4E99-4552-855A-48C1D9346449/Documents
Xcode version: 12.0
iOS device: iPhone X
iOS version: 14.1
Edit
I tried to use this code to copy the database from the app bundle to the document directory, but it gives the error Unable to copy file:
copyFileToDocumentsFolder(nameForFile: "Database", extForFile: "db")
func copyFileToDocumentsFolder(nameForFile: String, extForFile: String) {
let documentsURL = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first!
let destURL = documentsURL.appendingPathComponent(nameForFile).appendingPathExtension(extForFile)
guard let sourceURL = Bundle.main.url(forResource: nameForFile, withExtension: extForFile)
else {
print("Source File not found.")
return
}
let fileManager = FileManager.default
do {
try fileManager.copyItem(at: sourceURL, to: destURL)
} catch {
print("Unable to copy file")
}
}

Answer 1

You can use url or path: with this codes you get the address of your data base, but you have to have your database file already there when your app use this address to find your databace! if you use this address, without having real file there, your app will crash. So if you have problem about copying your databace file let me know!
Version: 1.0.0
let appBaseURL = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0].standardizedFileURL
let databaseURL = appBaseURL.appendingPathComponent("Database").appendingPathExtension("db").standardizedFileURL
let databasePath = databaseURL.path
Update Version: 2.0.0
This codes down are the most simplest and cleanest code about copy and paste on planet Earth for Swift and SwiftUI! You can not find better than this:
// If you want see your file in device or give user access to the file do this 2 steps:
// 1 - add this one ("Application supports iTunes file sharing" -> Yes) from (info.plist)
// 2 -add this one ("Supports opening documents in place" -> Yes) from (info.plist)
let fileName = "omid"
let fileExtension = "jpeg"
let appBaseURL = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0].standardizedFileURL
let pasteFileURL = appBaseURL.appendingPathComponent(fileName).appendingPathExtension(fileExtension).standardizedFileURL
let copyFileURL = Bundle.main.bundleURL.appendingPathComponent(fileName).appendingPathExtension(fileExtension).standardizedFileURL
if FileManager.default.fileExists(atPath: appBaseURL.path)
{
print("appBaseFolder already exists!")
}
else
{
do{ try FileManager.default.createDirectory(at: appBaseURL, withIntermediateDirectories: true, attributes: nil); print("appBaseFolder successfully created!") }
catch{ print("Error in creating appBaseFolder!") }
}
if FileManager.default.fileExists(atPath: pasteFileURL.path)
{
print("The selected file already exists!")
}
else
{
do{ try FileManager.default.copyItem(at: copyFileURL, to: pasteFileURL); print("The selected file successfully copied!") }
catch { print("Error with copying selected file!") }
}
Version: 3.0.0 (The GM Version)
//▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
// If you want see your file in device or give user access to the file do this 2 steps:
// 1 - add this one ("Application supports iTunes file sharing" -> Yes) from (info.plist)
// 2 - add this one ("Supports opening documents in place" -> Yes) from (info.plist)
//...........................................................
let fileName = "omid"
let fileExtension = "jpeg"
//...........................................................
let appBaseURL = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0].standardizedFileURL
let pasteFileURL = appBaseURL.appendingPathComponent(fileName).appendingPathExtension(fileExtension).standardizedFileURL
let copyFileURL = Bundle.main.bundleURL.appendingPathComponent(fileName).appendingPathExtension(fileExtension).standardizedFileURL
//▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
//...........................................................
if FileManager.default.fileExists(atPath: appBaseURL.path)
{
print("appBaseFolder already exists!")
}
else
{
do{ try FileManager.default.createDirectory(at: appBaseURL, withIntermediateDirectories: true, attributes: nil); print("appBaseFolder successfully created!") }
catch{ print("Error in creating appBaseFolder!") }
}
//...........................................................
//...........................................................
if FileManager.default.fileExists(atPath: copyFileURL.path)
{
//...........................................................
if FileManager.default.fileExists(atPath: pasteFileURL.path)
{
print("The selected file already exists!")
}
else
{
do{ try FileManager.default.copyItem(at: copyFileURL, to: pasteFileURL); print("The selected file successfully copied!") }
catch { print("Error with copying selected file!") }
}
//...........................................................
}
else
{
print("The selected file not exists for copy Action!")
}
//...........................................................

Answer 2

As I already mentioned in your last question the Bundle is read-only. you need to move/copy your database to another directory that you can read/write to it. If you don't want the user to have access to the file you should copy it to that application support directory:
extension URL {
static let database: URL = {
let applicationSupport = FileManager.default.urls(for: .applicationSupportDirectory, in: .userDomainMask).first!
let bundleID = Bundle.main.bundleIdentifier ?? "company name"
let subDirectory = applicationSupport.appendingPathComponent(bundleID, isDirectory: true)
let destination = subDirectory.appendingPathComponent("Database.db")
if !FileManager.default.fileExists(atPath: destination.path) {
let source = Bundle.main.url(forResource: "Database", withExtension: "db")!
do {
try FileManager.default.createDirectory(at: subDirectory, withIntermediateDirectories: true, attributes: nil)
print("directory created")
try FileManager.default.copyItem(at: source, to: destination)
print("file copied successfully")
} catch {
print("Unable to copy file. return the bundle read-only version")
return source
}
}
print("database found return app suport database read-write url")
return destination
}()
}
let dbURL = URL.database

Answer 3

The Mac (and by extension the Simulator) has a case-insensitive file system. iOS has a case-sensitive file system. If it's working on the simulator, but not the device, I expect the capitalization of your database filename is incorrect. The most likely mistake would be that it's database.db rather than Database.db.