Allow merging to the existing pdf

[Jan Blaha]

Based on this forum thread
https://forum.jsreport.net/topic/441/adding-content-to-existing-pdf

I prepared a demo which would allow to merge existing pdf, but the pdf utils is not able to do the merge
export (23).zip

Stack

(while reading XRef): Error: Invalid XRef stream header
XRefParseException
    at XRefParseExceptionClosure (eval at <anonymous> (E:\temp5\node_modules\pdf2json\lib\pdf.js:64:1), <anonymous>:379:34)
    at eval (eval at <anonymous> (E:\temp5\node_modules\pdf2json\lib\pdf.js:64:1), <anonymous>:384:3)
    at Object.<anonymous> (E:\temp5\node_modules\pdf2json\lib\pdf.js:64:1)
    at Module._compile (module.js:612:30)
    at Object.Module._extensions..js (module.js:623:10)
    at Module.load (module.js:531:32)
    at tryModuleLoad (module.js:494:12)
    at Function.Module._load (module.js:486:3)
    at Module.require (module.js:556:17)
    at require (internal/module.js:11:18)
    at Object.<anonymous> (E:\temp5\node_modules\pdf2json\pdfparser.js:8:10)

[Jan Blaha]

The script loading the pdf from file system in demo could load it using jsreport-proxy from asset instead. That would make it really cool.

Note that fixing this will also make possible to append/prepend existing pdf.

[Jan Blaha]

I improved support for merging external static pdfs.
It is now released in the beta if someone wants to try it out.

npm i jsreport-pdf-utils@beta

We will cover this scenario in the docs after we ship it officially.

[BJR Matos]

this feature is published now in 1.2.0, which is part of jsreport 2.3.0, docs are about to be released

[sjd2021]

Are there any examples where this is being leveraged?