java.nio.file.NoSuchFileException - Download files from GCS

Question

I am attempting to download a file from Google Cloud Storage. I'm using Google's Github code here on line 1042. I believe my error is with the file path. The path variable is to state where the file is downloaded to and the new name of it, correct? Note, I'm using a JSP button to start the process. To make it easier to solve for myself I replaced the String and Path variables with Strings instead of the HttpServletRequest.

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    // [START storage_download_file]
    // The name of the bucket to access
    String bucketName = "media";

    // The name of the remote file to download
    String srcFilename = "File.rtf";

    // The path to which the file should be downloaded
    Path destFilePath = Paths.get("/Volumes/Macintosh HD/Users/ab/Desktop/File.rtf");

    // Instantiate a Google Cloud Storage client
    Storage storage = StorageOptions.getDefaultInstance().getService();

    // Get specific file from specified bucket
    Blob blob = storage.get(BlobId.of(bucketName, srcFilename));

    // Download file to specified path
    blob.downloadTo(destFilePath);
    // [END storage_download_file]
}

Caused by: java.nio.file.NoSuchFileException: /Volumes/Macintosh HD/Users/ab/Desktop/File.rtf

does this path exist on your machine where code is running? check path and file both — Pandey Amit, Oct 19 '18 at 18:58
The code is running on App Engine of GCP. I'm confused about the Path variable. I'm understanding that the code will download File.rtf from GCS to my computer. It will place the downloaded file at the specified path with the new name, same name in this case, that is specified at the end of the path. The path ends up being /Users/ab/Desktop/File.rtf. Excluding the /Volumes/Macintosh HD. I get the same error though. — Alex Brandt, Oct 19 '18 at 21:01
If that code runs on Google App Engine, it will try to write on the Google App Engine machine, not on your computer. To download it to your computer, you would have to write the downloaded bytes to the HTTP response output stream. — JB Nizet, Oct 19 '18 at 21:55

score 0 · Accepted Answer · answered Dec 17 '18 at 20:19

Code found on GitHub in the Google APIs. The part and concept I was missing is

OutputStream outStream = response.getOutputStream();

This sends the data back to the client's browser.

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {   

    /**** Define variables ****/
    Storage storage = StorageOptions.getDefaultInstance().getService();
    String bucketName = "bucketName";
    String objectName = "objectName";

    /**** Setting The Content Attributes For The Response Object ****/
    String mimeType = "application/octet-stream";
    response.setContentType(mimeType);

    /**** Setting The Headers For The Response Object ****/
    String headerKey = "Content-Disposition";
    String headerValue = String.format("attachment; filename=\"%s\"", objectName);
    response.setHeader(headerKey, headerValue);

    /**** Get the Output Stream of the Response Object****/
    OutputStream outStream = response.getOutputStream();

    /**** Call download method ****/
    run(storage, bucketName, objectName, outStream);
}

private void run(Storage storage, String bucketName, String objectName, OutputStream outStream)throws IOException {
    /**** Getting the blob ****/
    BlobId blobId = BlobId.of(bucketName, objectName);
    Blob blob = storage.get(blobId);

    /**** Writing the content that will be sent in the response ****/
    byte[] content = blob.getContent();
    outStream.write(content);
    outStream.close();
}

java.nio.file.NoSuchFileException - Download files from GCS

1 Answers1