refactor: Implement test run helper to work with services

packages/backend/src/helpers/compute-parameters.ts

@@ -0,0 +1,43 @@
+import Step from '../models/step';
+import ExecutionStep from '../models/execution-step';
+import get from 'lodash.get';
+
+const variableRegExp = /({{step\.[\da-zA-Z-]+(?:\.[\da-zA-Z-]+)+}})/g;
+
+export default function computeParameters(
+  parameters: Step['parameters'],
+  executionSteps: ExecutionStep[]
+): Step['parameters'] {
+  const entries = Object.entries(parameters);
+  return entries.reduce((result, [key, value]: [string, unknown]) => {
+    if (typeof value === 'string') {
+      const parts = value.split(variableRegExp);
+
+      const computedValue = parts
+        .map((part: string) => {
+          const isVariable = part.match(variableRegExp);
+          if (isVariable) {
+            const stepIdAndKeyPath = part.replace(/{{step.|}}/g, '') as string;
+            const [stepId, ...keyPaths] = stepIdAndKeyPath.split('.');
+            const keyPath = keyPaths.join('.');
+            const executionStep = executionSteps.find((executionStep) => {
+              return executionStep.stepId === stepId;
+            });
+            const data = executionStep?.dataOut;
+            const dataValue = get(data, keyPath);
+            return dataValue;
+          }
+
+          return part;
+        })
+        .join('');
+
+      return {
+        ...result,
+        [key]: computedValue,
+      };
+    }
+
+    return result;
+  }, {});
+}