From 578f3d34a12352f7399e01115d3b81355222113a Mon Sep 17 00:00:00 2001
From: Chaim Lev-Ari <chaim.levi-ari@portainer.io>
Date: Wed, 18 Oct 2023 08:30:42 +0200
Subject: [PATCH] refactor(custom-templates): return parse error

---
 ...-create-custom-template-view.controller.js |  2 +-
 ...be-edit-custom-template-view.controller.js |  2 +-
 .../createCustomTemplateViewController.js     |  2 +-
 .../editCustomTemplateViewController.js       |  2 +-
 .../custom-templates/components/utils.ts      | 39 ++++++++++++-------
 5 files changed, 28 insertions(+), 19 deletions(-)

diff --git a/app/kubernetes/custom-templates/kube-create-custom-template-view/kube-create-custom-template-view.controller.js b/app/kubernetes/custom-templates/kube-create-custom-template-view/kube-create-custom-template-view.controller.js
index 2535d1ae3..ac65f2d04 100644
--- a/app/kubernetes/custom-templates/kube-create-custom-template-view/kube-create-custom-template-view.controller.js
+++ b/app/kubernetes/custom-templates/kube-create-custom-template-view/kube-create-custom-template-view.controller.js
@@ -83,7 +83,7 @@ class KubeCreateCustomTemplateViewController {
       return;
     }
 
-    const variables = getTemplateVariables(templateStr);
+    const [variables] = getTemplateVariables(templateStr);
 
     const isValid = !!variables;
 
diff --git a/app/kubernetes/custom-templates/kube-edit-custom-template-view/kube-edit-custom-template-view.controller.js b/app/kubernetes/custom-templates/kube-edit-custom-template-view/kube-edit-custom-template-view.controller.js
index 100e16dc5..a5ef19ae9 100644
--- a/app/kubernetes/custom-templates/kube-edit-custom-template-view/kube-edit-custom-template-view.controller.js
+++ b/app/kubernetes/custom-templates/kube-edit-custom-template-view/kube-edit-custom-template-view.controller.js
@@ -112,7 +112,7 @@ class KubeEditCustomTemplateViewController {
       return;
     }
 
-    const variables = getTemplateVariables(templateStr);
+    const [variables] = getTemplateVariables(templateStr);
 
     const isValid = !!variables;
 
diff --git a/app/portainer/views/custom-templates/create-custom-template-view/createCustomTemplateViewController.js b/app/portainer/views/custom-templates/create-custom-template-view/createCustomTemplateViewController.js
index 068491039..9d4d76182 100644
--- a/app/portainer/views/custom-templates/create-custom-template-view/createCustomTemplateViewController.js
+++ b/app/portainer/views/custom-templates/create-custom-template-view/createCustomTemplateViewController.js
@@ -206,7 +206,7 @@ class CreateCustomTemplateViewController {
       return;
     }
 
-    const variables = getTemplateVariables(templateStr);
+    const [variables] = getTemplateVariables(templateStr);
 
     const isValid = !!variables;
 
diff --git a/app/portainer/views/custom-templates/edit-custom-template-view/editCustomTemplateViewController.js b/app/portainer/views/custom-templates/edit-custom-template-view/editCustomTemplateViewController.js
index e19731df2..67171afc8 100644
--- a/app/portainer/views/custom-templates/edit-custom-template-view/editCustomTemplateViewController.js
+++ b/app/portainer/views/custom-templates/edit-custom-template-view/editCustomTemplateViewController.js
@@ -178,7 +178,7 @@ class EditCustomTemplateViewController {
       return;
     }
 
-    const variables = getTemplateVariables(templateStr);
+    const [variables] = getTemplateVariables(templateStr);
 
     const isValid = !!variables;
 
diff --git a/app/react/portainer/custom-templates/components/utils.ts b/app/react/portainer/custom-templates/components/utils.ts
index 2c2362264..6fca12f39 100644
--- a/app/react/portainer/custom-templates/components/utils.ts
+++ b/app/react/portainer/custom-templates/components/utils.ts
@@ -4,31 +4,40 @@ import Mustache from 'mustache';
 import { VariableDefinition } from './CustomTemplatesVariablesDefinitionField/CustomTemplatesVariablesDefinitionField';
 
 export function getTemplateVariables(templateStr: string) {
-  const template = validateAndParse(templateStr);
+  const [template, error] = validateAndParse(templateStr);
 
   if (!template) {
-    return null;
+    return [null, error] as const;
   }
 
-  return template
-    .filter(([type, value]) => type === 'name' && value)
-    .map(([, value]) => ({
-      name: value,
-      label: '',
-      defaultValue: '',
-      description: '',
-    }));
+  return [
+    template
+      .filter(([type, value]) => type === 'name' && value)
+      .map(([, value]) => ({
+        name: value,
+        label: '',
+        defaultValue: '',
+        description: '',
+      })),
+    null,
+  ] as const;
 }
-
-function validateAndParse(templateStr: string) {
+type TemplateSpans = ReturnType<typeof Mustache.parse>;
+function validateAndParse(
+  templateStr: string
+): readonly [TemplateSpans, null] | readonly [null, string] {
   if (!templateStr) {
-    return [];
+    return [[] as TemplateSpans, null] as const;
   }
 
   try {
-    return Mustache.parse(templateStr);
+    return [Mustache.parse(templateStr), null] as const;
   } catch (e) {
-    return null;
+    if (!(e instanceof Error)) {
+      return [null, 'Parse error'] as const;
+    }
+
+    return [null, e.message] as const;
   }
 }