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Support gzip in range request / Explicitly set accept-encoding: identity

See original GitHub issue

I’m using react-pdf, which in turn uses pdf.js (awesome library, guys!), for a web application that shows open governmental meeting documents (demo). I noticed that for large PDF files, loading takes a while, and it seems like pdf.js downloads the entire file before rendering the first page.

The docs mention that PDF.js fetches only the necessary data, if the server supports Content-Range header / Range requests.

The server (Google Cloud Storage) seems to support ranges (example file).

GET https://storage.googleapis.com/ori-static/api.notubiz.nl/document/6131301 HTTP/1.1
Range: bytes=0-1999

The maintainer of react-pdf told me it should work If we simply pass a URL to pdfjs.getDocument, but it does not.

Is it true that getDocument should use the Range header if only a URL is passed?

Am I missing something? Should I manually create a PDFDataRangeTransport? Thanks in advance for your time!

Issue Analytics

State:
Created 4 years ago
Comments:14 (2 by maintainers)

Top GitHub Comments

1reaction

timvandermeijcommented, Aug 5, 2019

Let’s reopen this. @yurydelendik @brendandahl Do you have any comments on https://github.com/mozilla/pdf.js/issues/11027#issuecomment-518180185?

0reactions

Snuffleupaguscommented, Feb 2, 2020

According to the specifications, see e.g. the XMLHttpRequest specification which links to the relevant part of the Fetch specification, the Accept-Encoding cannot be set (other than the by browser itself); see also https://developer.mozilla.org/en-US/docs/Glossary/Forbidden_header_name Hence it won’t be possible to add Accept-Encoding: identity to the network requests made by the PDF.js library.

With regards to adding support for gzip in the various stream implementations, that would risk adding a lot of additional complexity to the relevant code (not to mention the time/effort required to implement/review/test something like that). Furthermore, the problem in this issue seem to be limited to a particular server rather than be a widespread issue.

All-in-all, it seems that WONTFIX probably is the appropriate resolution for this issue.

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