Data_Binding_JSON

Data Binding & JSON

Two recurring enterprise needs: exposing FundsXML to JSON APIs, and binding FundsXML to typed objects.

FundsXML ⇄ JSON (verified)

python/fundsxml_json.py — to-json / from-json / roundtrip (stdlib + lxml). Stable JSON shape (document / fund / shareClasses / positions / assets); from-json produces XSD-valid FundsXML 4.2.9. Lossless for the positions core, intentionally lossy for issuer / derivative / regulatory detail (same scope boundary as Database_Integration/).

python3 Data_Binding_JSON/python/fundsxml_json.py to-json \
  FundsXML_Files/4.2.9/positions/Mixed-Fund_Positions.xml fund.json
python3 Data_Binding_JSON/python/fundsxml_json.py roundtrip \
  FundsXML_Files/4.2.9/positions/Mixed-Fund_Positions.xml regenerated.xml
XSD_Validation/cli/validate.sh \
  https://github.com/fundsxml/schema/releases/download/4.2.9/FundsXML.xsd \
  regenerated.xml   # or a local FundsXML.xsd path

Verified: NAV, position count and percentage-sum preserved through XML → JSON → XML.

Binding: native vs. generated

java/NativeBinding.java — native Java, no JAXB: a thin hand-written binding over DOM + XPath into Java records. Verified on 4.2.9 and 4.0.0 (FundsXML 4.x is backward compatible, so one binding spans versions). This is the recommended default: the FundsXML schema is very large, so a full generated model is heavy and brittle to maintain.

Generated-binding references (when you do want codegen)

Stack	Tool	Command (against a local FundsXML.xsd)
Java	JAXB xjc	xjc -d src -p org.fundsxml.model schema/FundsXML.xsd
Python	xsdata	xsdata --package fundsxml.model schema/FundsXML.xsd
.NET	xsd.exe / XmlSerializer	xsd.exe /classes /namespace:FundsXml.Model schema\FundsXML.xsd

All three consume the official released schema on disk. Codegen needs the local file (and, for 4.2.9, its xmldsig-core-schema.xsd sibling beside it), so fetch it once:

mkdir -p schema && B=https://github.com/fundsxml/schema/releases/download/4.2.9
curl -sSL -o schema/FundsXML.xsd "$B/FundsXML.xsd"
curl -sSL -o schema/xmldsig-core-schema.xsd "$B/xmldsig-core-schema.xsd"

Trade-off: generated models are type-safe but regenerate on every schema bump and produce thousands of classes; the native binding stays small and version-tolerant. Pick per use case.

CI runs the JSON round-trip (XSD-validated, figures asserted) and the native Java binding on every push.