How to add XML data to ArangoDB?

Problem

You want to store XML data files into a database to have the ability to make queries onto them.

This example was written for and tested with ArangoDB 3.1 and the corresponding Java driver.

Solution

Since version 3.1.0 the arangodb-java-driver supports writing, reading and querying of raw strings containing the JSON documents.

With JsonML you can convert a XML string into a JSON string and back to XML again.

Converting XML into JSON with JsonML example:

String string = "<recipe name=\"bread\" prep_time=\"5 mins\" cook_time=\"3 hours\"> "
        + "<title>Basic bread</title> "
        + "<ingredient amount=\"8\" unit=\"dL\">Flour</ingredient> "
        + "<ingredient amount=\"10\" unit=\"grams\">Yeast</ingredient> "
        + "<ingredient amount=\"4\" unit=\"dL\" state=\"warm\">Water</ingredient> "
        + "<ingredient amount=\"1\" unit=\"teaspoon\">Salt</ingredient> "
        + "<instructions> "
        + "<step>Mix all ingredients together.</step> "
        + "<step>Knead thoroughly.</step> "
        + "<step>Cover with a cloth, and leave for one hour in warm room.</step> "
        + "<step>Knead again.</step> "
        + "<step>Place in a bread baking tin.</step> "
        + "<step>Cover with a cloth, and leave for one hour in warm room.</step> "
        + "<step>Bake in the oven at 180(degrees)C for 30 minutes.</step> "
        + "</instructions> "
        + "</recipe> ";

JSONObject jsonObject = JSONML.toJSONObject(string);
System.out.println(jsonObject.toString());

The converted JSON string:

{
   "prep_time" : "5 mins",
   "name" : "bread",
   "cook_time" : "3 hours",
   "tagName" : "recipe",
   "childNodes" : [
      {
         "childNodes" : [
            "Basic bread"
         ],
         "tagName" : "title"
      },
      {
         "childNodes" : [
            "Flour"
         ],
         "tagName" : "ingredient",
         "amount" : 8,
         "unit" : "dL"
      },
      {
         "unit" : "grams",
         "amount" : 10,
         "tagName" : "ingredient",
         "childNodes" : [
            "Yeast"
         ]
      },
      {
         "childNodes" : [
            "Water"
         ],
         "tagName" : "ingredient",
         "amount" : 4,
         "unit" : "dL",
         "state" : "warm"
      },
      {
         "childNodes" : [
            "Salt"
         ],
         "tagName" : "ingredient",
         "unit" : "teaspoon",
         "amount" : 1
      },
      {
         "childNodes" : [
            {
               "tagName" : "step",
               "childNodes" : [
                  "Mix all ingredients together."
               ]
            },
            {
               "tagName" : "step",
               "childNodes" : [
                  "Knead thoroughly."
               ]
            },
            {
               "childNodes" : [
                  "Cover with a cloth, and leave for one hour in warm room."
               ],
               "tagName" : "step"
            },
            {
               "tagName" : "step",
               "childNodes" : [
                  "Knead again."
               ]
            },
            {
               "childNodes" : [
                  "Place in a bread baking tin."
               ],
               "tagName" : "step"
            },
            {
               "tagName" : "step",
               "childNodes" : [
                  "Cover with a cloth, and leave for one hour in warm room."
               ]
            },
            {
               "tagName" : "step",
               "childNodes" : [
                  "Bake in the oven at 180(degrees)C for 30 minutes."
               ]
            }
         ],
         "tagName" : "instructions"
      }
   ]
}

Saving the converted JSON to ArangoDB example:

ArangoDB.Builder arango = new ArangoDB.Builder().build();
ArangoCollection collection = arango.db().collection("testCollection")
DocumentCreateEntity<String> entity = collection.insertDocument(
                jsonObject.toString());
String key = entity.getKey();

Reading the stored JSON as a string and convert it back to XML example:

String rawJsonString = collection.getDocument(key, String.class);
String xml = JSONML.toString(rawJsonString);
System.out.println(xml);

Example output:

<recipe _id="RawDocument/6834407522" _key="6834407522" _rev="6834407522"
         cook_time="3 hours" name="bread" prep_time="5 mins">
  <title>Basic bread</title>
  <ingredient amount="8" unit="dL">Flour</ingredient>
  <ingredient amount="10" unit="grams">Yeast</ingredient>
  <ingredient amount="4" state="warm" unit="dL">Water</ingredient>
  <ingredient amount="1" unit="teaspoon">Salt</ingredient>
  <instructions>
    <step>Mix all ingredients together.</step>
    <step>Knead thoroughly.</step>
    <step>Cover with a cloth, and leave for one hour in warm room.</step>
    <step>Knead again.</step>
    <step>Place in a bread baking tin.</step>
    <step>Cover with a cloth, and leave for one hour in warm room.</step>
    <step>Bake in the oven at 180(degrees)C for 30 minutes.</step>
  </instructions>
</recipe>

Note: The fields mandatory to ArangoDB documents are added; If they break your XML schema you have to remove them.

Query raw data example:

String queryString = "FOR t IN testCollection FILTER t.cook_time == '3 hours' RETURN t";
ArangoCursor<String> cursor = arango.db().query(queryString, null, null, String.class);
while (cursor.hasNext()) {
    JSONObject jsonObject = new JSONObject(cursor.next());
    String xml = JSONML.toString(jsonObject);
    System.out.println("XML value: " + xml);
}

❮ The BaseDocument object Import Graph data ❯