Develop Reference

nodejs extract/decompress all content of .gz compressed files to directory

i have a file in the file system named temp.gz
the temp gzip file contains files and folder
i would like to extract them and have them in a folder like we would normally unzip a file in OS.
i have tried below code but thats not meant for extracting files to folder.
const unzip = zlib.createUnzip();
var input = fs.createReadStream(inFilename); /path/to/temp.gz
var output = fs.createWriteStream(outFilename); /path/to/output/folder
Above didnt work and i believe the reason is that it writes to a file and i have provided a directoy.
my requirement is extract files to directory.
zlib.gzip(responseData, (err, buffer) => {
// Calling gunzip method
zlib.gunzip(buffer, (err, buffer) => {
console.log(buffer,pathFileName);
fs.appendFileSync(pathFileName, buffer);
});
});
above i was trying to unzip as per the docs and write buffer to the output file and didnt create a folder as expected and didnt add the files there
sure i am missing something but not sure what.

MIME Type for excel file from Blazor Server side project

I am trying to download a List of Items as excel from Blazor server side project . I used CsvHelper to generate the byte[] from the list and using the below code to download the byte[] content as excel file .
The code from Blazor Component is like below [ Click event of button to download excel]
#inject IJSRuntime JsRuntime
private async Task ExportToExcel()
{
jobStarted = true;
var fileBytes= ExportHelper.ConvertContactDataToCsv(); // This will return byte[] of contacts
if (await JsRuntime.InvokeAsync<bool>("confirm", $"Do you want to Export?"))
{
var fileName = $"Contacts";
await JsRuntime.InvokeAsync<object>("saveAsFile", fileName, Convert.ToBase64String(fileBytes));
}
jobStarted = false;
}
The Javascript code is like below
window.saveAsFile = function (fileName, byteBase64) {
var link = this.document.createElement('a');
link.download = fileName;
link.href = "data:application/vnd.ms-excel;base64," + byteBase64;
this.document.body.appendChild(link);
link.click();
this.document.body.removeChild(link);
}
Execution of this generates the file without any issues , but while opening the file using Microsoft Excel the warning message is like
The file format and extension of 'Contacts.xls' don't match. The file
could be corrupted or unsafe. Unless you trust its source, don't open
it. Do you want to open it anyway?
And if i ignore the warning and proceed with opening all contents in excel looks good
Now i tried to generate file with extension xlsx and different mime type inside JS code The changes are like
var fileName = $"Contacts.xlsx";
and inside JS tried these 2 combinations separately
link.href = "data:application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;base64," + byteBase64;
link.href = "data:application/octet-stream;base64," + byteBase64;
The code executed without any issues and files getting generated but while opening file the warning is like
Excel cannot open the file 'Contacts.xlsx' because the file format
for the file extension is not valid.’ Verify that the file has not
been corrupted and that the file extension matches the format of the
file
I am not able to open the file at all.
So what is the right MIME type to be used to ensure downloaded excel file can be opened in Excel without warnings

Since you are using CsvHelper (via ConvertContactDataToCsv) your output file is a Comma Separated Value text file, not a binary Excel .xls file.
Don't use the .xls file extension, instead use e.g. .csv;
so Contacts.csv instead of Contacts.xls.
For the mime type, you might use text/csv.
But foremost, it is the wrong file extension that makes Excel error on that file.

Save body text to temp file in Formidable

I have a text field in the fields parameter of the form that I want to write to a file and save to the temp directory, similar to how Formidable handles file uploads. Does Formidable have methods to access its temp file writing capabilities?
Example:
tempFile = writeToTempFile(fields.textField)
files.tempFile = tempFile

Javascript create zip file

I am developing a website using react.js and admin-on-rest. One feature is allowing users to upload a pdf file.
I get the file as type FILE and want to get the file from FILE, compress it to zip, and then make it to type FILE.
So it should be FILE -> origin file -> zip file -> FILE from zip file.
I tried JSZip but still can not figure it out.
Any help is appreciated. Thanks

You can use JSZIP.
**use npm to install JSZIP
let zip = require('jszip')();
//hoping you have already taken input
let input = document.getElementById('fileInput'); // fileInput is id of my input element
let file = input.files[0];
let allZip = zip.file(file.name, file);
console.log(allZip)

Hi Garrick following are the steps you need to take.
1) handle fileupload in a rest wrapper
https://marmelab.com/admin-on-rest/RestClients.html#decorating-your-rest-client-example-of-file-upload
the above example is for image upload. But you will essentially be doing the same thing.
2)
const addUploadCapabilities = requestHandler => (type, resource, params) => {
if (type === 'UPDATE' && resource === 'posts') {
//use jszip to zip file here and package it however you need
// call the API with zipped file
} return requestHandler(type, resource, params);
};

There is a small app called jszip for this. Try, it would help. https://stuk.github.io/jszip/

Can I get upload path at runtime?

I need to get upload path of my uploaded files via jquery-file-uploader.
$('.new_plotphoto').fileupload({
done: function (e, data) {
var filess = data.files[0];
var filename = filess.name;
var filepath = filess.filepath;
console.log(filename); // this shows filename
console.log(filepath); // this shows undefined
}
});

Path of uploading file is a secure feature. From W3C File API docs about file name:
The name of the file; on getting, this must return the name of the
file as a string. There are numerous file name variations on different
systems; this is merely the name of the file, without path
information.
File path will be enabled only then you upload directory:
<input type=file multiple directory webkitdirectory onchange="console.log(this.files)">
In this case webkitRelativePath(for WebKit browsers) field of file object will be not empty. But it will show path only inside uploaded directory.
Also note that iOS browsers then uploading images always have this file name: image.jpg and no info about path.