Update app.py

app.py

@@ -1,56 +1,118 @@
 import streamlit as st
 import json
+from jsonschema import validate, ValidationError
+import re
 
-# Simulate some mock existing resources (you can customize this)
+# Mock existing resources (customizable)
 existing_resources = {
     "storageAccount1": {
         "type": "Microsoft.Storage/storageAccounts",
         "location": "East US",
-        "status": "existing"
+        "status": "existing",
+        "properties": {
+            "accountType": "Standard_LRS"
+        }
     }
 }
 
-# Function to simulate ARM template deployment evaluation
+# ARM template schema (simplified version)
+arm_schema = {
+    "type": "object",
+    "properties": {
+        "$schema": {"type": "string"},
+        "contentVersion": {"type": "string"},
+        "parameters": {"type": "object"},
+        "variables": {"type": "object"},
+        "resources": {
+            "type": "array",
+            "items": {
+                "type": "object",
+                "required": ["type", "name", "location"],
+                "properties": {
+                    "type": {"type": "string"},
+                    "name": {"type": "string"},
+                    "location": {"type": "string"},
+                    "properties": {"type": "object"}
+                }
+            }
+        },
+        "outputs": {"type": "object"}
+    },
+    "required": ["$schema", "contentVersion", "resources"]
+}
+
+def validate_template(template):
+    try:
+        validate(instance=template, schema=arm_schema)
+        return True, "Template is valid."
+    except ValidationError as e:
+        return False, f"Template validation error: {e.message}"
+
+def resolve_template_expressions(template):
+    def resolve_expression(match):
+        expr = match.group(1)
+        parts = expr.split('.')
+        if parts[0] == 'parameters':
+            return str(template.get('parameters', {}).get(parts[1], {}).get('defaultValue', ''))
+        elif parts[0] == 'variables':
+            return str(template.get('variables', {}).get(parts[1], ''))
+        return match.group(0)
+
+    template_str = json.dumps(template)
+    resolved_str = re.sub(r'\[(\w+\.\w+)\]', resolve_expression, template_str)
+    return json.loads(resolved_str)
+
 def simulate_deployment(arm_template):
     try:
-        # Load ARM template from pasted JSON
         template = json.loads(arm_template)
         
-        # Initialize lists for tracking resources to be created, updated, or deleted
+        # Validate template
+        is_valid, validation_message = validate_template(template)
+        if not is_valid:
+            return [], [], [], validation_message
+
+        # Resolve expressions
+        resolved_template = resolve_template_expressions(template)
+
         resources_to_create = []
         resources_to_update = []
         resources_to_delete = []
+        resource_details = []
 
-        # Check the resources in the template
-        for resource in template.get('resources', []):
+        for resource in resolved_template.get('resources', []):
             resource_name = resource.get('name')
             resource_type = resource.get('type')
             location = resource.get('location')
+            properties = resource.get('properties', {})
 
-            # Simulate creation or update
             if resource_name in existing_resources:
-                if (existing_resources[resource_name]['type'] == resource_type 
-                    and existing_resources[resource_name]['location'] == location):
+                existing = existing_resources[resource_name]
+                if (existing['type'] == resource_type and
+                    existing['location'] == location and
+                    existing['properties'] == properties):
                     resources_to_update.append(resource_name)
                 else:
-                    resources_to_create.append(resource_name)  # Re-create if major properties change
+                    resources_to_create.append(resource_name)
             else:
                 resources_to_create.append(resource_name)
 
-        # Simulate deletion (if something in the template isn't in the mock cloud)
+            resource_details.append({
+                "name": resource_name,
+                "type": resource_type,
+                "location": location,
+                "properties": properties
+            })
+
         for resource_name in existing_resources:
-            if resource_name not in [r.get('name') for r in template.get('resources', [])]:
+            if resource_name not in [r.get('name') for r in resolved_template.get('resources', [])]:
                 resources_to_delete.append(resource_name)
 
-        # Return results
-        return resources_to_create, resources_to_update, resources_to_delete
-
+        return resources_to_create, resources_to_update, resources_to_delete, resource_details, "Simulation completed successfully."
     except json.JSONDecodeError:
-        st.error("Invalid JSON format. Please check your ARM template.")
-        return [], [], []
+        return [], [], [], [], "Invalid JSON format. Please check your ARM template."
 
 # Streamlit UI
-st.title("ARM Template Simulator")
+st.title("Enhanced ARM Template Simulator")
 st.subheader("Paste your ARM template below to simulate its deployment.")
 
 # Input box for ARM template
@@ -59,27 +121,39 @@ template_input = st.text_area("Paste ARM Template JSON here:", height=300)
 # Button to simulate the evaluation
 if st.button("Simulate Template"):
     if template_input:
-        resources_to_create, resources_to_update, resources_to_delete = simulate_deployment(template_input)
-
-        # Display results
-        st.subheader("Simulation Results:")
+        resources_to_create, resources_to_update, resources_to_delete, resource_details, message = simulate_deployment(template_input)
         
-        st.write("### Resources to be Created:")
-        if resources_to_create:
-            st.write(resources_to_create)
-        else:
-            st.write("No new resources will be created.")
+        st.subheader("Simulation Results:")
+        st.write(message)
 
-        st.write("### Resources to be Updated:")
-        if resources_to_update:
-            st.write(resources_to_update)
-        else:
-            st.write("No resources will be updated.")
+        if resources_to_create or resources_to_update or resources_to_delete:
+            st.write("### Resources to be Created:")
+            if resources_to_create:
+                st.write(resources_to_create)
+            else:
+                st.write("No new resources will be created.")
+
+            st.write("### Resources to be Updated:")
+            if resources_to_update:
+                st.write(resources_to_update)
+            else:
+                st.write("No resources will be updated.")
+
+            st.write("### Resources to be Deleted:")
+            if resources_to_delete:
+                st.write(resources_to_delete)
+            else:
+                st.write("No resources will be deleted.")
 
-        st.write("### Resources to be Deleted:")
-        if resources_to_delete:
-            st.write(resources_to_delete)
+            st.write("### Detailed Resource Information:")
+            for resource in resource_details:
+                st.write(f"**Name:** {resource['name']}")
+                st.write(f"**Type:** {resource['type']}")
+                st.write(f"**Location:** {resource['location']}")
+                st.write("**Properties:**")
+                st.json(resource['properties'])
+                st.write("---")
         else:
-            st.write("No resources will be deleted.")
+            st.write("No changes detected in the simulation.")
     else:
-        st.error("Please paste an ARM template to simulate.")
+        st.error("Please paste an ARM template to simulate.")