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Converting XML to JSON in Rust 23 May 2021
rust

I generally default to using JSON for data interchange but there are still a myriad of formats of XML out there, for which I have created the xmltojson crate. I originally wrote this one night to help me get an XML dataset into JSON so that I could use PostgreSQL’s JSONB column type, but I only recently published it to crates.io since it may be useful for others.

Cargo.toml

[dependencies]
xmltojson = "0"

The xmltojson crate implements Stefan Goessner’s xml2json which results in a fairly straightforward conversion of XML data structure into JSON. Take the following XML for example:

<ol class="xoxo">
    <li>Subject 1
        <ol>
            <li>subpoint a</li>
            <li>subpoint b</li>
        </ol>
    </li>
    <li>
        <span>Subject 2</span>
        <ol compact="compact">
            <li>subpoint c</li>
            <li>subpoint d</li>
        </ol>
    </li>
</ol>

This XML structured will be rapidly converted into the following JSON, with attributes and children encoded into the structure:

{
    "ol": {
        "@class":"xoxo",
        "li": [
            {
                "#text":"Subject 1",
                "ol":{
                    "li":[
                        "subpoint a",
                        "subpoint b"
                    ]
                }
            },
            {
                "span":"Subject 2",
                "ol": {
                    "@compact":"compact",
                    "li": [
                        "subpoint c",
                        "subpoint d"
                    ]
                }
            }
        ]
    }
}

There are some oddities with the JSON encoding of XML, particularly around CDATA, but overall I have been quite pleased turning XML into JSON which I can more easily query with jq, PostgreSQL, or even ingest into Elasticsearch.

If you happen to find any bugs, please submit pull requests on GitHub