How to use the azure-kusto-ingest.IngestionMappingType.JSON function in azure-kusto-ingest

const clusterName = null;
const appId = null;
const appKey = null;
const authorityId = null;

const props = new IngestionProps({
    database: "Database",
    table: "Table",
    format: DataFormat.JSON,
    ingestionMapping : [
        new JsonColumnMapping("TargetColumn1", "$.sourceProp1"),
        new JsonColumnMapping("TargetColumn2", "$.sourceProp2"),
        new JsonColumnMapping("TargetColumn3", "$.sourceProp3")
    ],
    ingestionMappingType: IngestionMappingType.JSON,
    reportLevel: ReportLevel.FailuresAndSuccesses,
    reportMethod: ReportMethod.Queue

});

const ingestClient = new IngestClient(
    KustoConnectionStringBuilder.withAadApplicationKeyAuthentication(
        `https://ingest-${clusterName}.kusto.windows.net`, appId, appKey, authorityId
    ),
    props
);

const statusQueues = new IngestStatusQueues(ingestClient);

function waitForFailures() {
    statusQueues.failure.isEmpty((err, empty) => {