[ARM] Add diagnostics and potential changes to what-if output

src/azure-cli/azure/cli/command_modules/resource/_color.py

@@ -13,6 +13,8 @@ class Color(Enum):
     PURPLE = "\033[38;5;141m"
     BLUE = "\033[38;5;39m"
     GRAY = "\033[38;5;246m"
+    RED = "\033[38;5;203m"
+    DARK_YELLOW = "\033[38;5;136m"
     RESET = "\033[0m"
 
     def __str__(self):

src/azure-cli/azure/cli/command_modules/resource/_formatters.py

@@ -5,7 +5,7 @@
 
 from itertools import groupby
 
-from azure.mgmt.resource.resources.models import ChangeType, PropertyChangeType
+from azure.mgmt.resource.resources.models import ChangeType, PropertyChangeType, Level
 
 from ._symbol import Symbol
 from ._color import Color, ColoredStringBuilder
@@ -30,6 +30,12 @@
     PropertyChangeType.no_effect: Color.GRAY,
 }
 
+_diagnostic_level_to_color = {
+    Level.ERROR: Color.RED,
+    Level.WARNING: Color.DARK_YELLOW,
+    Level.INFO: Color.RESET,
+}
+
 _change_type_to_symbol = {
     ChangeType.create: Symbol.PLUS,
     ChangeType.delete: Symbol.MINUS,
@@ -73,8 +79,22 @@ def format_what_if_operation_result(what_if_operation_result, enable_color=True)
     builder = ColoredStringBuilder(enable_color)
     _format_noise_notice(builder)
     _format_change_type_legend(builder, what_if_operation_result.changes)
-    _format_resource_changes(builder, what_if_operation_result.changes)
-    _format_resource_changes_stats(builder, what_if_operation_result.changes)
+    _format_resource_changes(builder,
+                             what_if_operation_result.changes,
+                             definite_changes=True)
+    _format_resource_changes_stats(builder,
+                                   what_if_operation_result.changes,
+                                   definite_changes=True)
+    _format_resource_changes(builder,
+                             what_if_operation_result.potential_changes,
+                             definite_changes=False)
+    _format_resource_changes_stats(builder,
+                                   what_if_operation_result.potential_changes,
+                                   definite_changes=False)
+    _format_diagnostics(builder,
+                        what_if_operation_result.changes,
+                        what_if_operation_result.potential_changes,
+                        what_if_operation_result.diagnostics)
     return builder.build()
 
 
@@ -120,20 +140,24 @@ def populate_change_type_set(property_changes):
         builder.append_line(change_type.title())
 
 
-def _format_resource_changes_stats(builder, resource_changes):
-    builder.append_line().append("Resource changes: ")
+def _format_resource_changes_stats(builder, resource_changes, definite_changes=True):
+    if definite_changes:
+        builder.append_line().append("Resource changes: ")
 
-    if not resource_changes:
-        builder.append("no change.")
-        return
+        if not resource_changes:
+            builder.append("no change.")
+            return
+    elif resource_changes:
+        builder.append_line().append("Potential changes: ")
 
-    sorted_resource_changes = sorted(resource_changes, key=lambda x: _change_type_to_weight[x.change_type])
-    resource_changes_by_change_type = groupby(sorted_resource_changes, lambda x: x.change_type)
-    count_by_change_type = map(lambda x: (x[0], len(list(x[1]))), resource_changes_by_change_type)
-    count_by_change_type = filter(lambda x: x[1] > 0, count_by_change_type)
-    change_type_stats = map(lambda x: _format_change_type_count(x[0], x[1]), count_by_change_type)
+    if resource_changes:
+        sorted_resource_changes = sorted(resource_changes, key=lambda x: _change_type_to_weight[x.change_type])
+        resource_changes_by_change_type = groupby(sorted_resource_changes, lambda x: x.change_type)
+        count_by_change_type = map(lambda x: (x[0], len(list(x[1]))), resource_changes_by_change_type)
+        count_by_change_type = filter(lambda x: x[1] > 0, count_by_change_type)
+        change_type_stats = map(lambda x: _format_change_type_count(x[0], x[1]), count_by_change_type)
 
-    builder.append(", ".join(change_type_stats)).append(".")
+        builder.append(", ".join(change_type_stats)).append(".")
 
 
 def _format_change_type_count(change_type, count):  # pylint: disable=too-many-return-statements
@@ -155,15 +179,49 @@ def _format_change_type_count(change_type, count):  # pylint: disable=too-many-r
     raise ValueError(f"Invalid ChangeType: {change_type}")
 
 
-def _format_resource_changes(builder, resource_changes):
+def _format_diagnostics(builder, resource_changes, potential_changes, diagnostics):
+    short_circuited_resources = [r for r in (resource_changes or []) + (potential_changes or [])
+                                 if r.change_type == ChangeType.UNSUPPORTED]
+
+    diags = diagnostics or []
+
+    if len(short_circuited_resources) + len(diags) > 0:
+        builder.append_line()
+        builder.append_line()
+        builder.append(f"Diagnostics ({len(short_circuited_resources) + len(diags)}): ")
+        builder.append_line()
+
+        for change in short_circuited_resources:
+            with builder.new_color_scope(_diagnostic_level_to_color[Level.WARNING]):
+                builder.append(change.resource_id)
+                builder.append(" (Unsupported) ")
+                builder.append(change.unsupported_reason)
+                builder.append_line()
+
+        for diag in diags:
+            with builder.new_color_scope(_diagnostic_level_to_color[diag.level]):
+                builder.append(diag.target)
+                builder.append(" (")
+                builder.append(diag.code)
+                builder.append(") ")
+                builder.append(diag.message)
+                builder.append_line()
+
+
+def _format_resource_changes(builder, resource_changes, definite_changes=True):
     if not resource_changes:
         return
 
     num_scopes = len(set(map(_get_scope_uppercase, resource_changes)))
     resource_changes_by_scope = groupby(sorted(resource_changes, key=_get_scope_uppercase), _get_scope_uppercase)
 
     builder.append_line()
-    builder.append_line(f"The deployment will update the following {'scope:' if num_scopes == 1 else 'scopes'}")
+    if definite_changes:
+        builder.append("The deployment will update the following ")
+    else:
+        builder.append("The following change MAY OR MAY NOT be deployed to the following ")
+
+    builder.append_line('scope:' if num_scopes == 1 else 'scopes:')
 
     for _, resource_changes_in_scope in resource_changes_by_scope:
         resource_changes_in_scope_list = list(resource_changes_in_scope)

src/azure-cli/azure/cli/command_modules/resource/tests/latest/policy_definition_deploy_with_short_circuiting.json

@@ -0,0 +1,71 @@
+{
+  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
+  "contentVersion": "1.0.0.0",
+  "parameters": {
+    "random": {
+      "type": "bool",
+      "defaultValue": "[greater(int(utcNow('%f')), 4)]"
+    },
+    "denyLocation": {
+      "type": "string",
+      "defaultValue": "northeurope"
+    }
+  },
+  "variables": {
+      "policyDefinitionName": "policy-for-what-if-test"
+  },
+  "resources": [
+    {
+      "name": "[variables('policyDefinitionName')]",
+      "type": "Microsoft.Authorization/policyDefinitions",
+      "apiVersion": "2018-05-01",
+      "condition": "[parameters('random')]",
+      "properties": {
+        "policyType": "Custom",
+        "policyRule": {
+          "if": {
+            "field": "location",
+            "equals": "[parameters('denyLocation')]"
+          },
+          "then": {
+            "effect": "deny"
+          }
+        }
+      }
+    },
+    {
+      "name": "[format('{0}_{1}', variables('policyDefinitionName'), if(parameters('random'), '2', '3'))]",
+      "type": "Microsoft.Authorization/policyDefinitions",
+      "apiVersion": "2018-05-01",
+      "properties": {
+        "policyType": "Custom",
+        "policyRule": {
+          "if": {
+            "field": "location",
+            "equals": "[parameters('denyLocation')]"
+          },
+          "then": {
+            "effect": "deny"
+          }
+        }
+      }
+    },
+      {
+        "type": "Microsoft.Resources/deployments",
+        "apiVersion": "2024-11-01",
+        "name": "nestedDeployment",
+        "location": "[deployment().location]",
+        "properties": {
+          "mode": "Incremental",
+          "template": {
+            "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
+            "contentVersion": "1.0.0.0",
+            "resources": [],
+            "variables": {
+              "undecidable": "[parameters('random')]"
+            }
+          }
+        }
+      }
+  ]
+}