I'm trying to...
download a file (an MLModel) from a server
save that file to the device
re-launch the app
use the URL (path) that the file was saved to, to access the downloaded file.. so I don't have to re-download it every time the app launches
let download = URLSession.shared.downloadTask(with: url) { (urlOrNil, response, error) in
if let error = error {
print("❌ There was an error in \(#function) \(error)")
completion(nil)
return
}
// the location the mlModel is saved at
guard let fileURL = urlOrNil else {print("🔥❇️>>>\(#file) \(#line)"); return }
do {
//compiles the model
let compiledUrl = try MLModel.compileModel(at: fileURL)
//turns the model into an MLModel
let model = try MLModel(contentsOf: compiledUrl)
print("newModel Complete 🍪")
// find the app support directory
let fileManager = FileManager.default
// Finds a place to save the MLModel
let appSupportDirectory = try! fileManager.url(for: .applicationSupportDirectory,
in: .userDomainMask, appropriateFor: compiledUrl, create: true)
// create a permanent URL in the app support directory
let permanentUrl = appSupportDirectory.appendingPathComponent(compiledUrl.lastPathComponent)
print("🎨\(permanentUrl)")
// if the file exists, replace it. Otherwise, copy the file to the destination.
if fileManager.fileExists(atPath: permanentUrl.absoluteString) {
_ = try fileManager.replaceItemAt(permanentUrl, withItemAt: compiledUrl)
} else {
try fileManager.copyItem(at: compiledUrl, to: permanentUrl)
}
let newModel = try MLModel(contentsOf: permanentUrl)
print("🎟", newModel)
completion(newModel)
}catch{
print("❌ There was an error in \(#function) \(error) : \(error.localizedDescription)")
}
}.resume()
From what I understand, this is saving my MLModel to the "permanentUrl". So I restart the app, I don't run downloadTask again (because the MLModel should be saved?), and I try to access the MLModel that I copied to the permanentURL with this code
let permanentUrl = URL(string:"file:///var/mobile/Containers/Data/Application/659B2FEE-4384-4BBE-97D1-B1575BF1EB3B/Library/Application%20Support/CFNetworkDownload_v3EpLD.mlmodelc")
do {
let model = try MLModel(contentsOf: permanentUrl!)
print(model)
}catch{
print("❌ There was an error in \(#function) \(error) : \(error.localizedDescription)")
}
I get this Error
file:///var/mobile/Containers/Data/Application/659B2FEE-4384-4BBE-97D1-B1575BF1EB3B/Library/Application 귑ీƢupport/CFNetworkDownload_v3EpLD.mlmodelc does not exist" UserInfo={NSLocalizedDescription=file:///var/mobile/Containers/Data/Application/659B2FEE-4384-4BBE-97D1-B1575BF1EB3B/Library/Application 귑ీƢupport/CFNetworkDownload_v3EpLD.mlmodelc does not exist} : file:///var/mobile/Containers/Data/Application/659B2FEE-4384-4BBE-97D1-B1575BF1EB3B/Library/Application 귑ీƢupport/CFNetworkDownload_v3EpLD.mlmodelc does not exist
So I guess the MLModel wasn't saved? What am I missing here? I assume I saved the MLModel with downloadTask and I'm just not retrieving it the right way. How do I access the file that I had saved?
This was the answer.
inside of the downloadTask function, I printed the compiledUrl.lastPathComponent and saved it. Then, when I re-ran the app I ran this code to find the URL of the file.
// saved compiledUrl.lastPathComponent
let filename = "CFNetworkDownload_B9QvT1.mlmodelc"
let fileManager = FileManager.default
let appSupportDirectory = try! fileManager.url(for: .applicationSupportDirectory, in: .userDomainMask, appropriateFor: nil, create: true)
let permanentUrl = appSupportDirectory.appendingPathComponent(filename)
let model = try? MLModel(contentsOf: permanentUrl)
print(model)