NIFI-14149 Fix invalid MiNiFi flow json by setting the default value …

…of maxTimerDrivenThreadCount and update minifi-toolkit command set with examples

Signed-off-by: Ferenc Kis <briansolo1985@gmail.com>

This closes #9628.

minifi/minifi-toolkit/minifi-toolkit-assembly/README.md

@@ -48,7 +48,8 @@ After downloading the binary and extracting it, to run the MiNiFi Toolkit Conver
       java org.apache.nifi.minifi.toolkit.configuration.ConfigMain <command> options
 
       Valid commands include:
-      transform-yml: Transforms legacy MiNiFi flow config YAML into MiNiFi flow config JSON
+     - transform-nifi: Transform NiFi2 flow JSON format into MiNifi flow JSON format
+     - transform-yml: Transforms legacy MiNiFi flow config YAML into MiNiFi flow config JSON
 
 ## Example
 - You have an older version of MiNiFi located in <legacy_minifi_directory>.
@@ -57,6 +58,10 @@ After downloading the binary and extracting it, to run the MiNiFi Toolkit Conver
 ```
 ./config.sh transform-yml <legacy_minifi_directory>/conf/config.yml <legacy_minifi_directory>/conf/bootstrap.conf <latest_minifi_directory>/conf/flow.json.raw <latest_minifi_directory>/conf/bootstrap.conf
 ```
+- Run the following command to transform NiFi flow JSON format into MiNifi flow JSON format
+```
+./config.sh transform-nifi <downloaded_nifi2_flow_json_file> <minifi_flow_json_file> 
+```
 
 ## Note
 It's not guaranteed in all circumstances that the migration will result in a correct flow. For example if a processor's configuration has changed between version, the conversion tool won't be aware of this, and will use the deprecated property names. You will need to fix such issues manually.

minifi/minifi-toolkit/minifi-toolkit-configuration/src/main/java/org/apache/nifi/minifi/toolkit/configuration/json/TransformNifiCommandFactory.java

@@ -27,6 +27,7 @@
 import org.apache.nifi.minifi.toolkit.configuration.ConfigTransformException;
 import org.apache.nifi.minifi.toolkit.configuration.PathInputStreamFactory;
 import org.apache.nifi.minifi.toolkit.configuration.PathOutputStreamFactory;
+import org.apache.nifi.minifi.toolkit.schema.CorePropertiesSchema;
 import org.apache.nifi.registry.flow.RegisteredFlowSnapshot;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
@@ -63,8 +64,9 @@ private int transformNifiToJson(String[] args) {
             RegisteredFlowSnapshot registeredFlowSnapshot = readNifiFlow(sourceNiFiJsonPath);
             VersionedDataflow versionedDataflow = new VersionedDataflow();
             versionedDataflow.setRootGroup(registeredFlowSnapshot.getFlowContents());
-            versionedDataflow
-                    .setParameterContexts(new ArrayList<>(registeredFlowSnapshot.getParameterContexts().values()));
+            versionedDataflow.setParameterContexts(new ArrayList<>(registeredFlowSnapshot.getParameterContexts().values()));
+            versionedDataflow.setMaxTimerDrivenThreadCount(CorePropertiesSchema.DEFAULT_MAX_CONCURRENT_THREADS);
+
             persistFlowJson(versionedDataflow, targetMiNiFiJsonPath);
         } catch (ConfigTransformException e) {
             System.out.println("Unable to convert NiFi JSON to MiNiFi flow JSON: " + e);