Added support for consuming OpenApi 3.0 nullable required fields (#4696)

bin/openapi3/kotlin-client-petstore-nullable-required.sh

@@ -0,0 +1,35 @@
+#!/bin/sh
+
+SCRIPT="$0"
+echo "# START SCRIPT: $SCRIPT"
+
+while [ -h "$SCRIPT" ] ; do
+  ls=$(ls -ld "$SCRIPT")
+  link=$(expr "$ls" : '.*-> \(.*\)$')
+  if expr "$link" : '/.*' > /dev/null; then
+    SCRIPT="$link"
+  else
+    SCRIPT=$(dirname "$SCRIPT")/"$link"
+  fi
+done
+
+if [ ! -d "${APP_DIR}" ]; then
+  APP_DIR=$(dirname "$SCRIPT")/..
+  APP_DIR=$(cd "${APP_DIR}"; pwd)
+fi
+
+executable="./modules/openapi-generator-cli/target/openapi-generator-cli.jar"
+
+if [ ! -f "$executable" ]
+then
+  mvn clean package
+fi
+
+export JAVA_OPTS="${JAVA_OPTS} -Xmx1024M -DloggerPath=conf/log4j.properties"
+ags="generate -i modules/openapi-generator/src/test/resources/3_0/petstore-with-nullable-required.yaml -t modules/openapi-generator/src/main/resources/kotlin-client -g kotlin --artifact-id kotlin-petstore-nullable-required --additional-properties allowRequiredAsNullable=true -o samples/openapi3/client/petstore/kotlin-nullable-required $@"
+
+echo "Cleaning previously generated files if any from samples/openapi3/client/petstore/kotlin-nullable-required"
+rm -rf samples/openapi3/client/petstore/kotlin-nullable-required
+
+echo "Generating Kotling client..."
+java $JAVA_OPTS -jar $executable $ags