How to convert xml to a map in Elixir?

Question

Rails extends Hash with from_xml

xml = <<-XML
  <?xml version="1.0" encoding="UTF-8"?>
    <hash>
      <foo type="integer">1</foo>
      <bar type="integer">2</bar>
    </hash>
XML

hash = Hash.from_xml(xml)
# => {"hash"=>{"foo"=>1, "bar"=>2}}

I'm struggling to find any examples for how to do this in Elixir in a comparably easy way.

Something like:

Map.from_xml(xml)
# => %{"hash" => %{"foo" => 1, "bar" => 2}}

Answer 1

I looked at sweet_xml, which has some nice sigils for pulling out specific patterns of data. My issue with it that, it requires a pretty verbose setup on my part in order to specify all the paths I would need to get.

I also looked at Quinn, which parses xml into some other data structure which can be searched. I find intermediate data structures a bit weird to work with compared to a map.

The other issue is that both these libraries use xmerl, which looks like it creates new atoms from the xml it is parsing.

I decided to scratch my own itch as an exercise to see if I could and create my first hex package: https://github.com/homanchou/elixir-xml-to-map

It uses the erlsom erlang library behind the scenes which says that it uses string keys instead, which I think is safer since atoms are not garbage collected.

Given the response to this question it's apparently extremely taboo to even consider using this naive approach, so use with caution. The Readme details the shortcomings.

Answer 2

Try to use sweet_xml . You can return a map from the xml document using xmap function and basic usage of xpath. Here's an example .

Answer 3

还有一种基于SAX （XML 的简单 API）算法的工具： https ://github.com/xinz/sax_map