Having a very difficult time trying to run command line arguments through Swift. I need to run commands on SQL files that a user manually drags onto the app (so the file path is different every time).
The piping between my app and the command line is working (sending 'pwd' will return the correct response), but when I try sending the arguments I want I cannot get them to work. I have tried using both "bin/bash" and "usr/bin/env" to no avail.
Essentially I am trying to rebuild a database that has been corrupted, without having to go in through terminal and do it myself. Common errors I see across attempts include 'Launch path not accessible' or 'File or directory not found'. I have tried using 'chmod 6' through terminal to set the permissions on the file, but this still does not work. Any help on what I am doing wrong to access the file, or another way to try and rebuild a database, would be greatly appreciated.
func checkForCorruption(filePath: URL) -> (String?, Bool){
let folder = filePath.deletingLastPathComponent()
let arguments = ["cd \(folder.relativePath)", "sqlite3 Restaurant.sql", ".mode insert",".output dump.sql",".dump", ".exit"]
let task = Process()
task.launchPath = "bin/bash/"
task.arguments = arguments
let inPipe = Pipe()
task.standardInput = inPipe
let pipe = Pipe()
task.standardOutput = pipe
let errPipe = Pipe()
task.standardError = errPipe
var output : [String] = []
task.launch()
task.waitUntilExit()
let data = pipe.fileHandleForReading.readDataToEndOfFile()
let errData = errPipe.fileHandleForReading.readDataToEndOfFile()
if let out = NSString(data: data, encoding: String.Encoding.utf8.rawValue){
print(out)
}
if let errOut = NSString(data: errData, encoding: String.Encoding.utf8.rawValue){
print("error: \(errOut)")
}
let outHandle = pipe.fileHandleForReading
if var string = String(data: data, encoding: .utf8) {
string = string.trimmingCharacters(in: .newlines)
output = string.components(separatedBy: "\n")
do {
try string.write(toFile: "\(folder.relativePath)/dump.sql", atomically: true, encoding: String.Encoding.utf8)
}
catch _ {
print("something went wrong")
}
}
outHandle.readabilityHandler = { pipe in
print("reading")
if let line = String(data: pipe.availableData, encoding: String.Encoding.utf8) {
print("New ouput: \(line)")
} else {
print("Error decoding data: \(pipe.availableData)")
}
}
return ("", false)
}
I got some help at work, for anyone struggling with this, here is the answer (the print statement is just were the dump file is located).
let arguments = ["\(filePath.relativePath)", ".mode insert",".output dump.sql",".dump", ".exit"]
let task = Process()
task.launchPath = "/usr/bin/sqlite3"
print(FileManager.default.currentDirectoryPath)
Related
What I want to do: Download an S3 file (pdf) in a lambda and extract its text, using Rust.
The Error:
ERROR PDF error: Invalid file header
I checked the pdf file in the bucket, downloaded it from the console and everything looks correct, so something is breaking in the way I store the file.
How I am doing it:
let config = aws_config::load_from_env().await;
let client = s3::Client::new(&config);
// Get uploaded object in raw bucket (serde derived the json)
let key = event.records.get(0).unwrap().s3.object.key.clone();
let key = key.replace('+', " ");
let key = percent_encoding::percent_decode_str(&key).decode_utf8().unwrap().to_string();
let content = client
.get_object()
.bucket(raw_bucket_name)
.key(&key)
// .response_content_type("application/pdf") // this did not make any difference
.send()
.await?;
let mut bytes = content.body.into_async_read();
let file = tempfile::NamedTempFile::new()?;
let path = file.into_temp_path();
let mut file = tokio::fs::File::create(&path).await?;
tokio::io::copy(&mut bytes, &mut file).await?;
let content = pdf_extract::extract_text(path)?; // this line breaks
Versions:
tokio = { version = "1", features = ["macros"] }
aws-sdk-s3 = "0.21.0"
aws-config = "0.51.0"
pdf-extract = "0.6.4"
I feel like I misunderstood something in how to store the bytestream, but e.g. https://stackoverflow.com/a/62003659/4986655 do it in the same way afaiks.
Any help or pointers on what the issue might be or how to debug this are very welcome.
The following code is very simple. Open a file as a write, create a BufWriter using the file, and write a line of string.
The program reports no errors and returns an Ok(10) value, but the file just has no content and is empty.
#[tokio::test]
async fn save_file_async() {
let path = "./hello.txt";
let inner = tokio::fs::OpenOptions::new()
.create(true)
.write(true)
//.truncate(true)
.open(path)
.await
.unwrap();
let mut writer = tokio::io::BufWriter::new(inner);
println!(
"{} bytes wrote",
writer.write("1234567890".as_bytes()).await.unwrap()
);
}
Need an explicit flush:
writer.flush().await.unwrap();
I have the code to download two files from Server and store It to In local using URLSession (let dataTask = defaultSession.downloadTask(with: url)). Everything Is working fine only the problem is it's downloading first file it's giving me success but the second file is not downloading completely.. So, I hope there is a way to restart download for the second file that gives error ..
I think there is way of doing that and start looking into it and I found this delegate method .. but not much help .. can anyone please help me out how to restart download if it fails .. Do i have to use handleEventsForBackgroundURLSession to clear up previous downloads..?
// bellow download method will triggered when i get filenames I am passing it to this and path is optional here..
func download(path: String?, filenames: [String]) -> Int {
for filename in filenames {
var downloadFrom = "ftp://" + username! + ":"
downloadFrom += password!.addingPercentEncoding(withAllowedCharacters: .urlPasswordAllowed)! + "#" + address!
if let downloadPort = port {
downloadFrom += ":" + String(downloadPort) + "/"
} else {
downloadFrom += "/"
}
if let downloadPath = path {
if !downloadPath.isEmpty {
downloadFrom += downloadPath + "/"
}
}
downloadFrom += filename
if let url = URL(string: downloadFrom) {
let dataTask = defaultSession.downloadTask(with: url)
dataTask.resume()
}
}
return DLResponseCode.success
}
Please find delegate methods bellow ..
func urlSession(_ session: URLSession, downloadTask: URLSessionDownloadTask, didFinishDownloadingTo location: URL) {
var responseCode = DLResponseCode.success
// Move the file to a new URL
let fileManager = FileManager.default
let filename = downloadTask.originalRequest?.url?.lastPathComponent
let destUrl = cacheURL.appendingPathComponent(filename!)
do {
let data = try Data(contentsOf: location)
// Delete it if it exists first
if fileManager.fileExists(atPath: destUrl.path) {
do{
try fileManager.removeItem(at: destUrl)
} catch let error {
danLogError("Clearing failed downloadFOTA file failed: \(error)")
responseCode = DLResponseCode.datalogger.failToCreateRequestedProtocolPipe
}
}
try data.write(to: destUrl)
} catch {
danLogError("Issue saving data locally")
responseCode = DLResponseCode.datalogger.noDataConnection
}
// Complete the download message
let message = DLBLEDataloggerChannel.Commands.download(responseCode: responseCode).description
connectionManagerDelegate?.sendMessageToDatalogger(msg: message)
}
func urlSession(_ session: URLSession, task: URLSessionTask, didCompleteWithError error: Error?) {
if error == nil {
print("session \(session) download completed")
} else {
print("session \(session) download failed with error \(String(describing: error?.localizedDescription))")
// session.downloadTask(withResumeData: <#T##Data#>)
}
guard error != nil else {
return
}
danLogError("Session \(session) invalid with error \(String(describing: error))\n")
let responseCode = DLResponseCode.datalogger.failToCreateRequestedProtocolPipe
let message = DLBLEDataloggerChannel.Commands.download(responseCode: responseCode).description
connectionManagerDelegate?.sendMessageToDatalogger(msg: message)
}
// When I call didWriteData delegate method it's printing below data seems not dowloaded complete data ..
session <__NSURLSessionLocal: 0x103e37970> download task <__NSCFLocalDownloadTask: 0x108d2ee60>{ taskIdentifier: 2 } { running } wrote an additional 30028 bytes (total 988980 bytes) out of an expected 988980 bytes.
//error that I am getting for second file .. this error is coming some times not always but most of the times..
session <__NSURLSessionLocal: 0x103e37970> download failed with error Optional("cancelled")
Please help me out to figure it out .. If there is any way to handle download again after it fails or why it fails ..
The resume data, if the request is resumable, should be in the NSError object's userInfo dictionary.
Unfortunately, Apple seems to have completely trashed the programming guide for NSURLSession (or at least I can't find it in Google search results), and the replacement content in the reference is missing all of the sections that talk about how to do proper error handling (even the constant that you're looking for is missing), so I'm going to have to describe it all from memory with the help of looking at the headers. Ick.
The key you're looking for is NSURLSessionDownloadTaskResumeData.
If that key is present, its value is a small NSData blob. Store that, then use the Reachability API (with the actual hostname from that request's URL) to decide when to retry the request.
After Reachability tells you that the server is reachable, create a new download task with the resume data and start it.
I want to record audio with AudioKit. What I want to achieve is a buffer with 512 bytes if the buffer is full. It will translate the buffer info through TCP. And the current situation is that I only know how to restore the Audio data into a file like in the code below.
Can anyone provide some tips to achieve my goal?
Here is my code:
AKAudioFile.cleanTempDirectory()
AKSettings.bufferLength = .medium
do {
try AKSettings.setSession(category: .playAndRecord, with: .allowBluetoothA2DP)
} catch {
AKLog("Could not set session category.")
}
AKSettings.defaultToSpeaker = true
micMixer = AKMixer(mic)
micBooster = AKBooster(micMixer)
micBooster.gain = 0
recorder = try?AKNodeRecorder.init(node: micMixer)
if let file = recorder.audioFile {
print(file.directoryPath)
player = AKPlayer(audioFile: file)
}
player.isLooping = true
moogLadder = AKMoogLadder(player)
mainMixer = AKMixer(moogLadder, micBooster)
AudioKit.output = mainMixer
let clipRecoder = AKClipRecorder(node: mainMixer)
do {
try AudioKit.start()
} catch {
AKLog("AudioKit did not start!")
}
try! recorder.record()
I am new in Swift and I did not found anything about executing external programs or access external processes using Swing language.
Is it possible to do in the current stage of the language development or I should use Objective-C instead?
Maybe there are some Objective-C libraries that can be used inside my Swift program?
Thanks.
You can run external programs using NSTask. For example, from Circle and Square:
import Foundation
func executeCommand(command: String, args: [String]) -> String {
let task = NSTask()
task.launchPath = command
task.arguments = args
let pipe = NSPipe()
task.standardOutput = pipe
task.launch()
let data = pipe.fileHandleForReading.readDataToEndOfFile()
let output: String = NSString(data: data, encoding: NSUTF8StringEncoding)
return output
}
let commandOutput = executeCommand("/bin/echo", ["Hello, I am here!"])
println("Command output: \(commandOutput)")
Improved version of Rob's answer (in that you don't need to specify the full path of your executable), and also updated for Swift 3:
import Foundation
func execCommand(command: String, args: [String]) -> String {
if !command.hasPrefix("/") {
let commandFull = execCommand(command: "/usr/bin/which", args: [command]).trimmingCharacters(in: CharacterSet.whitespacesAndNewlines)
return execCommand(command: commandFull, args: args)
} else {
let proc = Process()
proc.launchPath = command
proc.arguments = args
let pipe = Pipe()
proc.standardOutput = pipe
proc.launch()
let data = pipe.fileHandleForReading.readDataToEndOfFile()
return String(data: data, encoding: String.Encoding.utf8)!
}
}