JsonPath

{
    "data": [
        {
            "metadata": {
                "ExternalId": "8744178",
                "UpdateTrigger": "914733e12c4cbea317c986e53ed2b38e49144cbf",
                "ReportId": "339C7AD3-C26A-4C14-80D7-C6041ECA6948",
                "Title": "Contact"
            }
        },
        {
            "metadata": {
                "RefreshKey": "c513e4eb-2707-4b01-97b3-f58456a41330",
                "ExternalId": "18795945",
                "UpdateTrigger": "refresh",
                "ReportId": "841372D8-7C16-4C9F-874E-5AB29FF9F459",
                "Title": "Plan-18795945"
            }
        },
        {
            "metadata": {
                "ExternalId": "9814235",
                "ReportId": "78392E27-9294-41AA-A1F2-98233BCFFCD5",
                "UpdateTrigger": "3a7bd6e970f492d935ec452dcee713035307d359",
                "Title": "RT-9814235"
            }
        }
    ]
}
// Find a node in an array by property value
$.data[?(@.metadata.ReportId=='78392E27-9294-41AA-A1F2-98233BCFFCD5')].metadata