preview pdf from google bucket signed url

Recently I am doing an archive project in Flasks. I want to view pdf with selectable text in a webpage using iframe or similar technology.

Since the pdf url is a signed url from google bucket, like this

https://storage.googleapis.com/bucket name/filename.pdf?X-Goog-Algorithm=GOOG4-RSA-SHA256&X-Goog-Credential=account%40 bluh bluh bluh(lots of other params)

It does not work with the pdf.js iframe:

<iframe class="iframe1" src="{{ url_for('static', filename='pdfjs-4.8.69-dist/web/viewer.html')}}?file= {{file_url}}"></iframe>

I have ensured the viewer.html and file_url are ready. How do I apply the iframe or similar methods?