catch model build exceptions

src/main/kotlin/KafkaTopology.kt

@@ -24,6 +24,7 @@ import org.apache.jena.rdf.model.Model
 import org.apache.jena.rdf.model.ModelFactory
 import org.apache.jena.rdf.model.Resource
 import org.apache.jena.rdf.model.ResourceFactory
+import org.apache.jena.riot.RiotException
 import org.apache.kafka.streams.StreamsBuilder
 import org.apache.kafka.streams.kstream.Predicate
 import org.memobase.rdf.EBUCORE
@@ -50,10 +51,26 @@ class KafkaTopology(private val settings: SettingsLoader) {
 
         val stream = builder.stream<String, String>(settings.inputTopic)
 
-        val instantiationBranch = stream
+        val model = stream
             .transformValues(HeaderExtractionTransformSupplier<String>())
             .mapValues { value -> createModel(value) }
-            .mapValues { value -> extractSubjects(value) }
+            .branch(
+                Predicate { _, value -> value != null },
+                Predicate { _, _ -> true }
+            )
+
+        model[1]
+            .mapValues { key, _ ->
+                Report(
+                    key,
+                    ReportStatus.failure,
+                    "Can't create model. Is there anything wrong with the data?"
+                )
+            }
+            .to(reportingTopic)
+
+        val instantiationBranch = model[0]
+            .mapValues { value -> extractSubjects(value!!) }
             .mapValues { readOnlyKey, value ->
                 enrichSftpLocator(
                     readOnlyKey,
@@ -170,9 +187,13 @@ class KafkaTopology(private val settings: SettingsLoader) {
             }
     }
 
-    private fun createModel(data: Pair<String, HeaderMetadata>): Pair<Model, HeaderMetadata> {
+    private fun createModel(data: Pair<String, HeaderMetadata>): Pair<Model, HeaderMetadata>? {
         val model = ModelFactory.createDefaultModel()
-        model.read(StringReader(data.first), "", Constant.rdfParserLang)
+        try {
+            model.read(StringReader(data.first), "", Constant.rdfParserLang)
+        } catch (ex: RiotException) {
+            return null
+        }
         return Pair(model, data.second)
     }