Download a Blob to file

Queries and Resources
1

I'd like to generate a zip file and download it, however it doesn't look like the utils.downloadFile method correctly handles a Blob as an input. I cannot convert it to a string, as the resulting output is no longer a valid .zip file and cannot be opened. Is it possible to get support for blobs in utils.downloadFile?

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2

Thank you for flagging this! Looks like this is a bug. We reproduced this on our end and added you to the bug ticket so we can keep you updated as a fix is merged

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3

Wicked, thanks Grace.

4

Hi, has this bug been fixed?

5

Any update please Grace?

6

Hey all — I just wanted to give an update here, generally it seems like this is a more general issue with how blobs are handled in Retool. One potential workaround is to try the following in a JS query:

function urlContentToBase64(url){
    return  fetch(url)
            .then( response => response.blob() )
            .then( blob => new Promise( callback =>{
                let reader = new FileReader() ;
                reader.onload = function(){ callback(this.result.split(',').pop()) } ;
                reader.readAsDataURL(blob) ;
            }) ) ;
}

//Usage example using await:
let data = await urlContentToBase64("https://file-examples-com.github.io/uploads/2017/02/zip_2MB.zip") ;

utils.downloadFile({base64Binary: data}, "test", "zip")
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