connect-rapidminer-graph

Connecting Mendix to RapidMiner / AnzoGraph via SPARQL

Use this skill when you need to fetch data from a RapidMiner graph mart (or any SPARQL 1.1 HTTP endpoint like AnzoGraph) and surface it in a Mendix app.

When to Use

• An external graph database exposes a SPARQL HTTP endpoint with Basic Auth
• You want the graph results to become Mendix entities (for display, search, further processing)
• You have read-only needs — the pattern fits SELECT queries that return tabular results

Endpoint shape

A RapidMiner / AnzoGraph graphmart endpoint looks like:

https://<host>/sparql/graphmart/<url-encoded-graphmart-uri>

Example:

https://graphstudio.mendixdemo.com/sparql/graphmart/http%3A%2F%2Fcambridgesemantics.com%2FGraphmart%2F3617250aca6a40d88972c1c0de38f86a

Two things to note:

1. The graphmart URI is URL-encoded and embedded in the path (colons and slashes become %3A / %2F).
2. SPARQL queries are sent as the POST body with content-type: application/sparql-query, and the response is JSON when Accept: application/sparql-results+json.

Verify with curl first:

curl -u '[email protected]:password' \
  -H 'Accept: application/sparql-results+json' \
  -H 'Content-Type: application/sparql-query' \
  --data-binary 'SELECT ?s WHERE { ?s a <http://example.com/Foo> } LIMIT 10' \
  'https://host/sparql/graphmart/<encoded-uri>'

If curl returns 200 and a JSON results.bindings array, you're ready to wire it into Mendix.

SPARQL JSON result shape

Every SPARQL HTTP result looks like this:

{
  "head": { "vars": ["customer", "customerId", "customerName"] },
  "results": {
    "bindings": [
      {
        "customer":     {"type": "uri",     "value": "http://.../Customer/0000000"},
        "customerId":   {"type": "literal", "value": "CUST001"},
        "customerName": {"type": "literal", "value": "Global Tech Solutions Inc."}
      }
    ]
  }
}

Each row in bindings is an object of {var: {type, value}}. A JSLT transformer flattens this to something directly mappable into Mendix entities.