opendaylight : Storing a sting in MDSAL - opendaylight

Question

I have a YANG model (known to MDSAL) which I am using in an opendaylight application. In my application, I am presented with a json formatted String which I want to store in the MDSAL database. I could use the builder of the object that I wish to store and set its with fields presented in the json formatted String one by one but this is laborious and error prone.
Alternatively I could post from within the application to the Northbound API which will eventually write to the MDSAL datastore.
Is there a simpler way to do this?
Thanks,

Answer 1

Assuming that your incoming JSON matches the structure of your YANG model exactly (does it?), I believe what you are really looking for is to transform that JSON into a "binding independant" (not setters of the generated Java class) internal model - NormalizedNode & Co. Somewhere in the controller or mdsal project there is a "codec" class that can do this.
You can either search for such code, and its usages (I find looking at tests are always useful) in the ODL controller and mdsal projects source code, or in other ODL projects which do similar things - I'm thinking specifically browsing around the jsonrpc and daexim projects sources; specifically this looks like it may inspire you: https://github.com/opendaylight/daexim/blob/stable/nitrogen/impl/src/main/java/org/opendaylight/daexim/impl/ImportTask.java
Best of luck.

Answer 2

Based on the information above, I constructed the following (which I am posting here to help others). I still do not know how to get rid of the deprecated reference to SchemaService (perhaps somebody can help).
private void importFromNormalizedNode(final DOMDataReadWriteTransaction rwTrx, final LogicalDatastoreType type,
final NormalizedNode<?, ?> data) throws TransactionCommitFailedException, ReadFailedException {
if (data instanceof NormalizedNodeContainer) {
#SuppressWarnings("unchecked")
YangInstanceIdentifier yid = YangInstanceIdentifier.create(data.getIdentifier());
rwTrx.put(type, yid, data);
} else {
throw new IllegalStateException("Root node is not instance of NormalizedNodeContainer");
}
}
private void importDatastore(String jsonData, QName qname) throws TransactionCommitFailedException, IOException,
ReadFailedException, SchemaSourceException, YangSyntaxErrorException {
// create StringBuffer object
LOG.info("jsonData = " + jsonData);
byte bytes[] = jsonData.getBytes();
InputStream is = new ByteArrayInputStream(bytes);
final NormalizedNodeContainerBuilder<?, ?, ?, ?> builder = ImmutableContainerNodeBuilder.create()
.withNodeIdentifier(new YangInstanceIdentifier.NodeIdentifier(qname));
try (NormalizedNodeStreamWriter writer = ImmutableNormalizedNodeStreamWriter.from(builder)) {
SchemaPath schemaPath = SchemaPath.create(true, qname);
LOG.info("SchemaPath " + schemaPath);
SchemaNode parentNode = SchemaContextUtil.findNodeInSchemaContext(schemaService.getGlobalContext(),
schemaPath.getPathFromRoot());
LOG.info("parentNode " + parentNode);
try (JsonParserStream jsonParser = JsonParserStream.create(writer, schemaService.getGlobalContext(),
parentNode)) {
try (JsonReader reader = new JsonReader(new InputStreamReader(is))) {
reader.setLenient(true);
jsonParser.parse(reader);
DOMDataReadWriteTransaction rwTrx = domDataBroker.newReadWriteTransaction();
importFromNormalizedNode(rwTrx, LogicalDatastoreType.CONFIGURATION, builder.build());
}
}
}
}