Likely incorrect nodegroup leads to a NullPointerException

[Ptival]

Raisin this issue because it might be an unintended error. As I work on a migration tool for nodegroups, I end up producing partially-repaired nodegroups that are likely incorrect, but in ways I do not quite know.

So far, I have been able to load them in SemTK to get useful error messages about mentions of classes / properties that don't exist in the ontology.

But with one of my recent changes, I am now seeing this exception:

http://localhost:12058/nodeGroupExecution/ingestFromCsvStringsById: Rest service call did not succeed
Details:
b'"message":"operations failed."
"rationale":"ingestion/fromCsv* threw java.lang.NullPointerException null
com.ge.research.semtk.belmont.NodeGroup.addJsonEncodedNodeGroup(NodeGroup.java:689)
com.ge.research.semtk.belmont.NodeGroup.getInstanceFromJson(NodeGroup.java:137)
com.ge.research.semtk.load.utility.SparqlGraphJson.getNodeGroup(SparqlGraphJson.java:294)

It seems a bit more catastrophic than the previous error messages I got, so it might be a candidate for a catch with some more explicit error message.

If more details would be useful:

• I'm using the ontology from https://github.com/ge-high-assurance/RACK/tree/v5.0
• I'm loading the following nodegroup:

Click for details

{
  "version": 2,
  "sparqlConn": {
    "name": "RACK local fuseki",
    "domain": "",
    "enableOwlImports": true,
    "model": [
      {
        "type": "fuseki",
        "url": "http://localhost:3030/RACK",
        "graph": "http://rack001/model"
      }
    ],
    "data": [
      {
        "type": "fuseki",
        "url": "http://localhost:3030/RACK",
        "graph": "http://rack001/data"
      }
    ]
  },
  "sNodeGroup": {
    "version": 11,
    "limit": 0,
    "offset": 0,
    "sNodeList": [
      {
        "deletionMode": "NO_DELETE",
        "fullURIName": "http://Turnstile/DevelopmentPlan#LowLevelRequirement",
        "instanceValue": null,
        "isReturned": true,
        "isRuntimeConstrained": false,
        "nodeList": [],
        "NodeName": "LowLevelRequirement",
        "propList": [
          {
            "KeyName": "identifier",
            "ValueType": "string",
            "relationship": "http://www.w3.org/2001/XMLSchema#string",
            "UriRelationship": "http://arcos.rack/PROV-S#identifier",
            "Constraints": "",
            "fullURIName": "",
            "SparqlID": "?identifier_ProducingLowLevelRequirement",
            "isReturned": true,
            "optMinus": 0,
            "isRuntimeConstrained": false,
            "instanceValues": [],
            "isMarkedForDeletion": false
          }
        ],
        "SparqlID": "?ProducingLowLevelRequirement",
        "subClassNames": [],
        "valueConstraint": ""
      },
      {
        "deletionMode": "NO_DELETE",
        "fullURIName": "http://Turnstile/DevelopmentPlan#SoftwareDesign",
        "instanceValue": null,
        "isReturned": false,
        "isRuntimeConstrained": false,
        "nodeList": [],
        "NodeName": "SoftwareDesign",
        "propList": [
          {
            "KeyName": "identifier",
            "ValueType": "string",
            "relationship": "http://www.w3.org/2001/XMLSchema#string",
            "UriRelationship": "http://arcos.rack/PROV-S#identifier",
            "Constraints": "",
            "fullURIName": "",
            "SparqlID": "?identifier_SoftwareDesign",
            "isReturned": true,
            "optMinus": 0,
            "isRuntimeConstrained": false,
            "instanceValues": [],
            "isMarkedForDeletion": false
          }
        ],
        "SparqlID": "?SoftwareDesign",
        "subClassNames": [],
        "valueConstraint": ""
      },
      {
        "deletionMode": "NO_DELETE",
        "fullURIName": "http://Turnstile/DevelopmentPlan#LowLevelRequirement",
        "instanceValue": null,
        "isReturned": true,
        "isRuntimeConstrained": false,
        "nodeList": [],
        "NodeName": "LowLevelRequirement",
        "propList": [
          {
            "KeyName": "identifier",
            "ValueType": "string",
            "relationship": "http://www.w3.org/2001/XMLSchema#string",
            "UriRelationship": "http://arcos.rack/PROV-S#identifier",
            "Constraints": "",
            "fullURIName": "",
            "SparqlID": "?identifier_ConsumingLowLevelRequirement",
            "isReturned": true,
            "optMinus": 0,
            "isRuntimeConstrained": false,
            "instanceValues": [],
            "isMarkedForDeletion": false
          }
        ],
        "SparqlID": "?ConsumingLowLevelRequirement",
        "subClassNames": [],
        "valueConstraint": ""
      },
      {
        "deletionMode": "NO_DELETE",
        "fullURIName": "http://Turnstile/DevelopmentPlan#DataAndControlCouple",
        "instanceValue": null,
        "isReturned": false,
        "isRuntimeConstrained": false,
        "nodeList": [
          {
            "SnodeSparqlIDs": [
              "?ConsumingLowLevelRequirement"
            ],
            "OptionalMinus": [
              1
            ],
            "Qualifiers": [
              ""
            ],
            "DeletionMarkers": [
              false
            ],
            "KeyName": "consumedBy",
            "ValueType": "ENTITY",
            "UriValueType": "http://arcos.rack/PROV-S#ENTITY",
            "ConnectBy": "consumedBy",
            "Connected": true,
            "UriConnectBy": "http://arcos.rack/REQUIREMENTS#consumedBy"
          },
          {
            "SnodeSparqlIDs": [
              "?SoftwareDesign"
            ],
            "OptionalMinus": [
              1
            ],
            "Qualifiers": [
              ""
            ],
            "DeletionMarkers": [
              false
            ],
            "KeyName": "createdBy",
            "ValueType": "ACTIVITY",
            "UriValueType": "http://arcos.rack/PROV-S#ACTIVITY",
            "ConnectBy": "createdBy",
            "Connected": true,
            "UriConnectBy": "http://arcos.rack/REQUIREMENTS#createdBy"
          },
          {
            "SnodeSparqlIDs": [
              "?ProducingLowLevelRequirement"
            ],
            "OptionalMinus": [
              1
            ],
            "Qualifiers": [
              ""
            ],
            "DeletionMarkers": [
              false
            ],
            "KeyName": "providedBy",
            "ValueType": "ENTITY",
            "UriValueType": "http://arcos.rack/PROV-S#ENTITY",
            "ConnectBy": "providedBy",
            "Connected": true,
            "UriConnectBy": "http://arcos.rack/REQUIREMENTS#providedBy"
          }
        ],
        "NodeName": "DataAndControlCouple",
        "propList": [
          {
            "KeyName": "identifier",
            "ValueType": "string",
            "relationship": "http://www.w3.org/2001/XMLSchema#string",
            "UriRelationship": "http://arcos.rack/PROV-S#identifier",
            "Constraints": "",
            "fullURIName": "",
            "SparqlID": "?identifier_DataAndControlCouple",
            "isReturned": true,
            "optMinus": 0,
            "isRuntimeConstrained": false,
            "instanceValues": [],
            "isMarkedForDeletion": false
          },
          {
            "KeyName": "description",
            "ValueType": "string",
            "relationship": "http://www.w3.org/2001/XMLSchema#string",
            "UriRelationship": "http://arcos.rack/PROV-S#description",
            "Constraints": "",
            "fullURIName": "",
            "SparqlID": "?text_DataAndControlCouple",
            "isReturned": true,
            "optMinus": 1,
            "isRuntimeConstrained": false,
            "instanceValues": [],
            "isMarkedForDeletion": false
          }
        ],
        "SparqlID": "?DataAndControlCouple",
        "subClassNames": [],
        "valueConstraint": ""
      }
    ],
    "orderBy": [],
    "unionHash": null
  },
  "importSpec": {
    "version": 1,
    "baseURI": "",
    "columns": [
      {
        "colId": "col_0",
        "colName": "identifier_ProducingLowLevelRequirement"
      },
      {
        "colId": "col_1",
        "colName": "identifier_SoftwareDesign"
      },
      {
        "colId": "col_2",
        "colName": "identifier_ConsumingLowLevelRequirement"
      },
      {
        "colId": "col_3",
        "colName": "identifier_DataAndControlCouple"
      },
      {
        "colId": "col_4",
        "colName": "text_DataAndControlCouple"
      }
    ],
    "dataValidator": [],
    "texts": [],
    "transforms": [
      {
        "transId": "trans_0",
        "name": "RemoveNulls",
        "transType": "replaceAll",
        "arg1": "null",
        "arg2": ""
      }
    ],
    "nodes": [
      {
        "sparqlID": "?ProducingLowLevelRequirement",
        "type": "http://Turnstile/DevelopmentPlan#LowLevelRequirement",
        "URILookupMode": "createIfMissing",
        "mapping": [],
        "props": [
          {
            "mapping": [
              {
                "colId": "col_0",
                "colName": null
              }
            ],
            "URILookup": [
              "?ProducingLowLevelRequirement"
            ],
            "URIRelation": "http://arcos.rack/PROV-S#identifier"
          }
        ]
      },
      {
        "sparqlID": "?SoftwareDesign",
        "type": "http://Turnstile/DevelopmentPlan#SoftwareDesign",
        "URILookupMode": "createIfMissing",
        "mapping": [],
        "props": [
          {
            "mapping": [
              {
                "colId": "col_1",
                "colName": null
              }
            ],
            "URILookup": [
              "?SoftwareDesign"
            ],
            "URIRelation": "http://arcos.rack/PROV-S#identifier"
          }
        ]
      },
      {
        "sparqlID": "?ConsumingLowLevelRequirement",
        "type": "http://Turnstile/DevelopmentPlan#LowLevelRequirement",
        "URILookupMode": "createIfMissing",
        "mapping": [],
        "props": [
          {
            "mapping": [
              {
                "colId": "col_2",
                "colName": null
              }
            ],
            "URILookup": [
              "?ConsumingLowLevelRequirement"
            ],
            "URIRelation": "http://arcos.rack/PROV-S#identifier"
          }
        ]
      },
      {
        "sparqlID": "?DataAndControlCouple",
        "type": "http://Turnstile/DevelopmentPlan#DataAndControlCouple",
        "URILookupMode": "createIfMissing",
        "mapping": [],
        "props": [
          {
            "mapping": [
              {
                "colId": "col_3",
                "colName": null
              }
            ],
            "URILookup": [
              "?DataAndControlCouple"
            ],
            "URIRelation": "http://arcos.rack/PROV-S#identifier"
          },
          {
            "mapping": [
              {
                "colId": "col_4",
                "colName": null
              }
            ],
            "URILookup": null,
            "URIRelation": "http://arcos.rack/PROV-S#description"
          }
        ]
      }
    ]
  }
}

[cuddihyge]

In the short term, neither colName nor URILookup (see the end of your file) should ever by null. URILookup should be [].

I can patch these things as they come up.

But properly verifying the JSON to support editing mistakes will be a non-trivial task. It would be nice to at least give a generic "JSON is bad" message.