From 7dc8d4c71a04e324422cc26c5474426537e6030e Mon Sep 17 00:00:00 2001
From: opreateodora <74269902+opreateodora@users.noreply.github.com>
Date: Fri, 13 Jan 2023 13:49:38 +0200
Subject: [PATCH] Add fallback mechanism (#1400)

* add fallback mechanism from python-executor to python when python server is down

* refactor

* refactor

* catch ExternalPythonScriptException

* rollback score version

* add log in ScriptEvaluator

Co-authored-by: TVerdesOprea <teodora.verdesoprea@microfocus.com>
---
 .../bindings/scripts/ScriptEvaluator.java     | 22 ++++++++++++++-----
 1 file changed, 17 insertions(+), 5 deletions(-)

diff --git a/cloudslang-runtime/src/main/java/io/cloudslang/lang/runtime/bindings/scripts/ScriptEvaluator.java b/cloudslang-runtime/src/main/java/io/cloudslang/lang/runtime/bindings/scripts/ScriptEvaluator.java
index cedf108700..c68e374f6c 100644
--- a/cloudslang-runtime/src/main/java/io/cloudslang/lang/runtime/bindings/scripts/ScriptEvaluator.java
+++ b/cloudslang-runtime/src/main/java/io/cloudslang/lang/runtime/bindings/scripts/ScriptEvaluator.java
@@ -18,8 +18,11 @@
 import io.cloudslang.runtime.api.python.PythonEvaluationResult;
 import io.cloudslang.runtime.api.python.PythonRuntimeService;
 import io.cloudslang.runtime.api.python.enums.PythonStrategy;
+import io.cloudslang.runtime.impl.python.external.ExternalPythonScriptException;
 import org.apache.commons.collections4.CollectionUtils;
 import org.apache.commons.lang3.StringUtils;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
 import org.python.core.Py;
 import org.python.core.PyObject;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -44,6 +47,8 @@
  */
 @Component
 public class ScriptEvaluator extends ScriptProcessor {
+
+    private static final Logger logger = LogManager.getLogger(ScriptEvaluator.class);
     private static String LINE_SEPARATOR = "\n";
     private static final String SYSTEM_PROPERTIES_MAP = "sys_prop";
     private static final String ACCESSED_RESOURCES_SET = "accessed_resources_set";
@@ -128,9 +133,9 @@ private Value doEvaluateExpressionExternalPython(String expr,
     }
 
     private Value doEvaluateExpressionPythonExecutor(String expr,
-                                                   Map<String, Value> context,
-                                                   Set<SystemProperty> systemProperties,
-                                                   Set<ScriptFunction> functionDependencies) {
+                                                     Map<String, Value> context,
+                                                     Set<SystemProperty> systemProperties,
+                                                     Set<ScriptFunction> functionDependencies) {
         Map<String, Serializable> pythonContext = createExternalPythonContext(context);
         boolean systemPropertiesDefined = false;
         if (functionDependencies.contains(ScriptFunction.GET_SYSTEM_PROPERTY) ||
@@ -142,8 +147,15 @@ private Value doEvaluateExpressionPythonExecutor(String expr,
                     (Serializable) prepareSystemPropertiesForExternalPython(systemProperties));
         }
 
-        PythonEvaluationResult result = pythonExecutorService.eval(
-                buildAddFunctionsScriptForExternalPython(functionDependencies), expr, pythonContext);
+        PythonEvaluationResult result;
+        try {
+            result = pythonExecutorService.eval(
+                    buildAddFunctionsScriptForExternalPython(functionDependencies), expr, pythonContext);
+        } catch (ExternalPythonScriptException exception) {
+            logger.error("Could not evaluate expressions on python executor, retrying with python");
+            result = pythonRuntimeService.eval(
+                    buildAddFunctionsScriptForExternalPython(functionDependencies), expr, pythonContext);
+        }
 
         //noinspection unchecked
         Set<String> accessedResources = (Set<String>) result.getResultContext().get(ACCESSED_RESOURCES_SET);