xmltojson

_posts/2021-05-23-converting-xml-to-json.md

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+---
+layout: post
+title: "Converting XML to JSON in Rust"
+tags:
+- 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](https://crates.io/crates/xmltojson) crate. I originally wrote this
+one night to help me get an XML dataset into JSON so that I could use
+[PostgreSQL's](https://postgresql.org) `JSONB` column type, but I only recently
+published it to [crates.io](https://crates.io) since it may be useful for
+others.
+
+**Cargo.toml**
+```toml
+[dependencies]
+xmltojson = "0"
+```
+
+
+The `xmltojson` crate implements [Stefan Goessner’s xml2json](https://goessner.net/download/prj/jsonxml/) which results in a fairly straightforward conversion of XML data structure into JSON. Take the following XML for example:
+
+
+```xml
+<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:
+
+```json
+{
+    "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](https://github.com/rtyler/xmltojson)