check for nulls

Author: rberlind

governance/third-generation/aws/aws-functions/aws-functions.sentinel

@@ -168,33 +168,37 @@ filter_resources_by_region = func(resources, region) {
     pck = r.provider_config_key
     p = tfconfig.providers[pck]
 
-    # First, process p itself
-    if "config" in keys(p) and "region" in keys(p.config) {
-      if validate_provider_region(p, region) {
-        resources_from_region[address] = r
-      }
-    } else {
-      # provider used by resource does not have region
-      # So, we process it as an alias to a root module provider
-      # A provider that does not have its own region should look like
-      # <module_address>:<provider>.<alias>
-      # we want to look at <provider>.<alias>
-      p_segments = strings.split(p.provider_config_key, ":")
-      if length(p_segments) == 1 {
-        # Current provider is already in root module
-        # So, it is not an alias to another provider
-        # Continue on to next resource in for loop
-        continue
-      }
-      # Get the provider in root module that current provider aliases
-      p_alias_name = p_segments[1]
-      p_alias = tfconfig.providers[p_alias_name]
-
-      # Process p_alias
-      if validate_provider_region(p_alias, region) {
-        resources_from_region[address] = r
-      }
-    } // end processing of p_alias
+    # First make sure p is not null
+    if p is not null {
+      # First, process p itself
+      if "config" in keys(p) and "region" in keys(p.config) {
+        if validate_provider_region(p, region) {
+          resources_from_region[address] = r
+        }
+      } else {
+        # provider used by resource does not have region
+        # So, we process it as an alias to a root module provider
+        # A provider that does not have its own region should look like
+        # <module_address>:<provider>.<alias>
+        # we want to look at <provider>.<alias>
+        # However, that might not exist
+        p_segments = strings.split(p.provider_config_key, ":")
+        if length(p_segments) == 1 {
+          # Current provider is already in root module
+          # So, it is not an alias to another provider
+          # Continue on to next resource in for loop
+          continue
+        }
+        # Get the provider in root module that current provider aliases
+        p_alias_name = p_segments[1]
+        p_alias = tfconfig.providers[p_alias_name]
+
+        # Process p_alias
+        if p_alias is not null and validate_provider_region(p_alias, region) {
+          resources_from_region[address] = r
+        }
+      } // end processing of p_alias
+    } // end check p not null
   } // end for resources
 
   return resources_from_region