Handle ResourceNotFoundException while iterating certificates (#646)

Handle ResourceNotFoundException while iterating certificates

SUMMARY

The module/utils/acm.py was not correctly handling deletion of certificates. While iterating over a list of certificates, the get_certificate function was making API calls to obtain more information about the certificates, but some certificates may be deleted while iterating.
Fixes #622

ISSUE TYPE


Bugfix Pull Request

COMPONENT NAME

acm.py
ADDITIONAL INFORMATION



Wow, it seems many tests are very flaky. I'm attempting to fix an issue in ACM, but problems occur elsewhere. Not to mention I raised this PR to fix #622, which was discovered while working on ansible-collections/community.aws#870. And I discovered other issues as well, and so it looks like it's not possible to make any progress without going down a tree of bug fixes.
TypeError: 'NoneType' object is not subscriptable
fatal: [testhost]: FAILED! => {
    "changed": false,
    "module_stderr": "Traceback (most recent call last):\n  File \"<stdin>\", line 121, in <module>\n  File \"<stdin>\", line 113, in _ansiballz_main\n  File \"<stdin>\", line 61, in invoke_module\n  File \"/usr/lib64/python3.8/runpy.py\", line 207, in run_module\n    return _run_module_code(code, init_globals, run_name, mod_spec)\n  File \"/usr/lib64/python3.8/runpy.py\", line 97, in _run_module_code\n    _run_code(code, mod_globals, init_globals,\n  File \"/usr/lib64/python3.8/runpy.py\", line 87, in _run_code\n    exec(code, run_globals)\n  File \"/tmp/ansible_ec2_vpc_igw_payload_g4o1kl_r/ansible_ec2_vpc_igw_payload.zip/ansible_collections/amazon/aws/plugins/modules/ec2_vpc_igw.py\", line 248, in <module>\n  File \"/tmp/ansible_ec2_vpc_igw_payload_g4o1kl_r/ansible_ec2_vpc_igw_payload.zip/ansible_collections/amazon/aws/plugins/modules/ec2_vpc_igw.py\", line 242, in main\n  File \"/tmp/ansible_ec2_vpc_igw_payload_g4o1kl_r/ansible_ec2_vpc_igw_payload.zip/ansible_collections/amazon/aws/plugins/modules/ec2_vpc_igw.py\", line 132, in process\n  File \"/tmp/ansible_ec2_vpc_igw_payload_g4o1kl_r/ansible_ec2_vpc_igw_payload.zip/ansible_collections/amazon/aws/plugins/modules/ec2_vpc_igw.py\", line 220, in ensure_igw_present\n  File \"/tmp/ansible_ec2_vpc_igw_payload_g4o1kl_r/ansible_ec2_vpc_igw_payload.zip/ansible_collections/amazon/aws/plugins/modules/ec2_vpc_igw.py\", line 158, in get_igw_info\nTypeError: 'NoneType' object is not subscriptable\n",
    "module_stdout": "",
    "msg": "MODULE FAILURE\nSee stdout/stderr for the exact error",
    "rc": 1
}

Reviewed-by: Alina Buzachis <None>
Reviewed-by: Jill R <None>

changelogs/fragments/646-acm-resource-not-found.yml

@@ -0,0 +1,3 @@
+bugfixes:
+- >-
+  aws_acm - No longer raising ResourceNotFound exception while retrieving ACM certificates.

plugins/module_utils/acm.py

@@ -38,6 +38,7 @@
 from ansible.module_utils._text import to_bytes
 from ansible.module_utils.common.dict_transformations import camel_dict_to_snake_dict
 
+from .core import is_boto3_error_code
 from .ec2 import AWSRetry
 from .ec2 import ansible_dict_to_boto3_tag_list
 from .ec2 import boto3_tag_list_to_ansible_dict
@@ -109,19 +110,28 @@ def get_certificates(self, client, module, domain_name=None, statuses=None, arn=
         for certificate in certificates:
             try:
                 cert_data = self.describe_certificate_with_backoff(client, certificate['CertificateArn'])
-            except (BotoCoreError, ClientError) as e:
+            except is_boto3_error_code('ResourceNotFoundException'):
+                # The certificate was deleted after the call to list_certificates_with_backoff.
+                continue
+            except (BotoCoreError, ClientError) as e:  # pylint: disable=duplicate-except
                 module.fail_json_aws(e, msg="Couldn't obtain certificate metadata for domain %s" % certificate['DomainName'])
 
             # in some states, ACM resources do not have a corresponding cert
             if cert_data['Status'] not in ['PENDING_VALIDATION', 'VALIDATION_TIMED_OUT', 'FAILED']:
                 try:
                     cert_data.update(self.get_certificate_with_backoff(client, certificate['CertificateArn']))
-                except (BotoCoreError, ClientError, KeyError) as e:
+                except is_boto3_error_code('ResourceNotFoundException'):
+                    # The certificate was deleted after the call to list_certificates_with_backoff.
+                    continue
+                except (BotoCoreError, ClientError, KeyError) as e:  # pylint: disable=duplicate-except
                     module.fail_json_aws(e, msg="Couldn't obtain certificate data for domain %s" % certificate['DomainName'])
             cert_data = camel_dict_to_snake_dict(cert_data)
             try:
                 tags = self.list_certificate_tags_with_backoff(client, certificate['CertificateArn'])
-            except (BotoCoreError, ClientError) as e:
+            except is_boto3_error_code('ResourceNotFoundException'):
+                # The certificate was deleted after the call to list_certificates_with_backoff.
+                continue
+            except (BotoCoreError, ClientError) as e:  # pylint: disable=duplicate-except
                 module.fail_json_aws(e, msg="Couldn't obtain tags for domain %s" % certificate['DomainName'])
 
             cert_data['tags'] = boto3_tag_list_to_ansible_dict(tags)