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Life & fun · April 13, 2018

PA

PDF Assembler – client-side PDF editing

Here's a neat hack I made recently to do basic PDF editing directly in a browser—without having to upload anything to a server. I was initially looking for a way to do simple PDF modification (extracting pages, merging, and adding page numbers). There are some good server-side tools for this (QPDF, PDFTk, PDFBox, iText, Hummus), but for better speed and privacy I really wanted a 100% client-side solution. There are a few good JavaScript PDF libraries for reading and displaying PDFs (pdf.js) and creating PDFs from scratch (jsPDF, PDFKit), but I couldn't find any for editing existing PDFs. So,…

What it does

In the maker’s words, at launch

Here's a neat hack I made recently to do basic PDF editing directly in a browser—without having to upload anything to a server. I was initially looking for a way to do simple PDF modification (extracting pages, merging, and adding page numbers). There are some good server-side tools for this (QPDF, PDFTk, PDFBox, iText, Hummus), but for better speed and privacy I really wanted a 100% client-side solution. There are a few good JavaScript PDF libraries for reading and displaying PDFs (pdf.js) and creating PDFs from scratch (jsPDF, PDFKit), but I couldn't find any for editing existing PDFs. So, I did what any self-respecting hacker would do, and rolled my own. :-) Actually, I found out that Mozilla's pdf.js solved half the problem, as it does an excellent job disassembling PDF files. So all I had to do was figure out a way to put them back together again. The result is PDF Assembler, now available on GitHub and NPM. I also put together a demonstration site (https://www.pdfcircus.com) which shows some examples of what it can do. I know PDF Assembler still needs some tweaking, but I think the basic idea is sound, and so far I've been pretty happy with how it works. Please take a look and let me know what you think. Thanks! PDF Assembler Links: Demonstration Site - https://www.pdfcircus.com GitHub - https://github.com/DevelopingMagic/pdfassembler NPM - https://www.npmjs.com/package/pdfassembler

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