fixup! Fix: Race between layer and Lambda update (#5927)

Author: dsotirho-ucsc

scripts/delete_lambda_versions.py

@@ -19,20 +19,19 @@
 
 
 def main():
-    lambdas = Lambdas().list_lambdas()
+    lambdas = Lambdas().list_deployment_lambdas()
     for lambda_ in lambdas:
-        response = aws.lambda_.list_versions_by_function(
-            FunctionName=lambda_.name
-        )
+        log.info('Fetching the published versions of %s', lambda_.name)
+        response = aws.lambda_.list_versions_by_function(FunctionName=lambda_.name)
         for version in response['Versions']:
-            if version['Version'] == '$LATEST':
+            version = version['Version']
+            if version == '$LATEST':
                 pass
             else:
-                version_number = version['Version']
-                log.info('Deleting published version %s of %s', version_number, lambda_.name)
+                log.info('Deleting published version %s of %s', version, lambda_.name)
                 aws.lambda_.delete_function(
                     FunctionName=lambda_.name,
-                    Qualifier=version_number
+                    Qualifier=version
                 )
 
 

src/azul/lambdas.py

@@ -98,12 +98,27 @@ def _lambda(self):
         return aws.lambda_
 
     def list_lambdas(self) -> list[Lambda]:
+        """
+        Return a list of all the Lambda functions in the AWS project
+        """
         return [
             Lambda.from_response(function)
             for response in self._lambda.get_paginator('list_functions').paginate()
             for function in response['Functions']
         ]
 
+    def list_deployment_lambdas(self) -> list[Lambda]:
+        """
+        Return a list of all the Lambda functions that are part of the currently
+        selected deployment.
+        """
+        return [
+            Lambda.from_response(function)
+            for response in self._lambda.get_paginator('list_functions').paginate()
+            for function in response['Functions']
+            if function['Environment']['Variables']['AZUL_DEPLOYMENT_STAGE'] == config.deployment_stage
+        ]
+
     def manage_lambdas(self, enabled: bool):
         paginator = self._lambda.get_paginator('list_functions')
         lambda_prefixes = [config.qualified_resource_name(lambda_infix) for lambda_infix in config.lambda_names()]

src/azul/terraform.py

@@ -709,8 +709,8 @@ def tf_config(self, app_name):
             assert 'layers' not in resource
             resource['layers'] = ['${aws_lambda_layer_version.dependencies.arn}']
             # Publishing the Lambda function as a new version prevents possible
-            # race conditions when an update to the function's configuration and
-            # code rely on the update of each other in order to work correctly.
+            # race conditions when there's a cyclic dependency between an update
+            # to the function's configuration and an update to its code
             resource['publish'] = True
             env = config.es_endpoint_env(
                 es_endpoint=(