Library for parsing epub document metadata (Haskell)




Library for parsing epub document metadata (Haskell)


Library for parsing and manipulating epub document metadata. Supports epub versions 2 and 3.

This library was constructed by studying the IDPF specifications for epub documents found here for version 2.x and here for version 3.x

Why was this done?

The motivation for this project grew out of my desire to take charge
of missing or incorrect epub metadata in books I have purchased. I
started out using the Calibre open source tools for examining this
info. Limitations and incomplete implementation of those tools led
me here to build a more complete implementation in the programming
language that I love beyond all others.

Why didn't I just use existing solutions?

Calibre ebook-meta utility

I experienced various problems using this software, such as:

  • Incomplete and in some cases incorrect handling of tags that can
    exist more than once (creator, contributor), particularly when they
    are differentiated using attributes according to the spec.

  • Unable to display many fields in the OPF Package Document metadata
    specification. Unable to manipulate data that is represented as
    attributes of tags in the OPF spec.

  • Astonishingly slow performance. A command-line renaming tool built with
    epub-metadata is more than 45 times faster at parsing and displaying
    epub metadata. I'm going to blame Python here for Calibre's
    performance. This has had a big impact on projects where I've been
    processing hundreds of epubs in batch operations.

epub on Hackage, epub E-Book construction support library

  • The focus of this project seems to be with building new documents,
    not parsing existing files. And there is a specific attempt to do more
    than the metadata, to gather up the content and other metafiles that
    make up an epub for creation.

  • Examining Codec.Ebook.OPF.Types, most of the metadata fields
    from the OPF Package Document spec are missing or aren't modeled
    thoroughly. I felt that to contribute to this project, I would have
    had to significantly rip up the types and redesign them.

  • At this time it seemed like a better solution for me to
    start fresh with modelling the types and code to manipulate them. That
    said, I would be very interested in combining the epub and epub-metadata
    projects at some point in some way that makes sense.

Using this library

Please see the Haddock documentation or source code for

This file has a working example of using this library.

Getting source

  • Download the cabalized source package from Hackage
  • Get the source with darcs: $ darcs get
  • Get the source with cabal-install: $ cabal get epub-metadata
  • Get the source with stack: $ stack unpack epub-metadata
  • If you're just looking, browse the source

And once you have it, building the usual way:

$ stack build
$ stack test
$ stack haddock


Dino Morelli <>