How to handle errors with boto3?
I am trying to figure how to do proper error handling with boto3.
I am trying to create an IAM user:
def create_user(username, iam_conn):
try:
user = iam_conn.create_user(UserName=username)
return user
except Exception as e:
return e
When the call to create_user succeeds, I get a neat object that contains the http status code of the API call and the data of the newly created user.
Example:
{'ResponseMetadata':
{'HTTPStatusCode': 200,
'RequestId': 'omitted'
},
u'User': {u'Arn': 'arn:aws:iam::omitted:user/omitted',
u'CreateDate': datetime.datetime(2015, 10, 11, 17, 13, 5, 882000, tzinfo=tzutc()),
u'Path': '/',
u'UserId': 'omitted',
u'UserName': 'omitted'
}
}
This works great. But when this fails (like if the user already exists), I just get an object of type botocore.exceptions.ClientError with only text to tell me what went wrong.
Example: ClientError('An error occurred (EntityAlreadyExists) when calling the CreateUser operation: User with name omitted already exists.',)
This (AFAIK) makes error handling very hard because I can't just switch on the resulting http status code (409 for user already exists according to the AWS API docs for IAM). This makes me think that I must be doing something the wrong way. The optimal way would be for boto3 to never throw exceptions, but juts always return an object that reflects how the API call went.
Can anyone enlighten me on this issue or point me in the right direction?
Use the response contained within the exception. Here is an example:
import boto3
from botocore.exceptions import ClientError
try:
iam = boto3.client('iam')
user = iam.create_user(UserName='fred')
print("Created user: %s" % user)
except ClientError as e:
if e.response['Error']['Code'] == 'EntityAlreadyExists':
print("User already exists")
else:
print("Unexpected error: %s" % e)
The response dict in the exception will contain the following:
['Error']['Code'] e.g. 'EntityAlreadyExists' or 'ValidationError'
['ResponseMetadata']['HTTPStatusCode'] e.g. 400
['ResponseMetadata']['RequestId'] e.g. 'd2b06652-88d7-11e5-99d0-812348583a35'
['Error']['Message'] e.g. "An error occurred (EntityAlreadyExists) ..."
['Error']['Type'] e.g. 'Sender'
For more information see:
boto3 error handling
botocore error handling
[Updated: 2018-03-07]
The AWS Python SDK has begun to expose service exceptions on clients (though not on resources) that you can explicitly catch, so it is now possible to write that code like this:
import botocore
import boto3
try:
iam = boto3.client('iam')
user = iam.create_user(UserName='fred')
print("Created user: %s" % user)
except iam.exceptions.EntityAlreadyExistsException:
print("User already exists")
except botocore.exceptions.ParamValidationError as e:
print("Parameter validation error: %s" % e)
except botocore.exceptions.ClientError as e:
print("Unexpected error: %s" % e)
Unfortunately, there is currently no documentation for these errors/exceptions but you can get a list of the core errors as follows:
import botocore
import boto3
[e for e in dir(botocore.exceptions) if e.endswith('Error')]
Note that you must import both botocore and boto3. If you only import botocore then you will find that botocore has no attribute named exceptions. This is because the exceptions are dynamically populated into botocore by boto3.
You can get a list of service-specific exceptions as follows (replace iam with the relevant service as needed):
import boto3
iam = boto3.client('iam')
[e for e in dir(iam.exceptions) if e.endswith('Exception')]
[Updated: 2021-09-07]
In addition to the aforementioned client exception method, there is also a third-party helper package named aws-error-utils.
I found it very useful, since the Exceptions are not documented, to list all exceptions to the screen for this package. Here is the code I used to do it:
import botocore.exceptions
def listexns(mod):
#module = __import__(mod)
exns = []
for name in botocore.exceptions.__dict__:
if (isinstance(botocore.exceptions.__dict__[name], Exception) or
name.endswith('Error')):
exns.append(name)
for name in exns:
print('%s.%s is an exception type' % (str(mod), name))
return
if __name__ == '__main__':
import sys
if len(sys.argv) <= 1:
print('Give me a module name on the $PYTHONPATH!')
print('Looking for exception types in module: %s' % sys.argv[1])
listexns(sys.argv[1])
Which results in:
Looking for exception types in module: boto3
boto3.BotoCoreError is an exception type
boto3.DataNotFoundError is an exception type
boto3.UnknownServiceError is an exception type
boto3.ApiVersionNotFoundError is an exception type
boto3.HTTPClientError is an exception type
boto3.ConnectionError is an exception type
boto3.EndpointConnectionError is an exception type
boto3.SSLError is an exception type
boto3.ConnectionClosedError is an exception type
boto3.ReadTimeoutError is an exception type
boto3.ConnectTimeoutError is an exception type
boto3.ProxyConnectionError is an exception type
boto3.NoCredentialsError is an exception type
boto3.PartialCredentialsError is an exception type
boto3.CredentialRetrievalError is an exception type
boto3.UnknownSignatureVersionError is an exception type
boto3.ServiceNotInRegionError is an exception type
boto3.BaseEndpointResolverError is an exception type
boto3.NoRegionError is an exception type
boto3.UnknownEndpointError is an exception type
boto3.ConfigParseError is an exception type
boto3.MissingParametersError is an exception type
boto3.ValidationError is an exception type
boto3.ParamValidationError is an exception type
boto3.UnknownKeyError is an exception type
boto3.RangeError is an exception type
boto3.UnknownParameterError is an exception type
boto3.AliasConflictParameterError is an exception type
boto3.PaginationError is an exception type
boto3.OperationNotPageableError is an exception type
boto3.ChecksumError is an exception type
boto3.UnseekableStreamError is an exception type
boto3.WaiterError is an exception type
boto3.IncompleteReadError is an exception type
boto3.InvalidExpressionError is an exception type
boto3.UnknownCredentialError is an exception type
boto3.WaiterConfigError is an exception type
boto3.UnknownClientMethodError is an exception type
boto3.UnsupportedSignatureVersionError is an exception type
boto3.ClientError is an exception type
boto3.EventStreamError is an exception type
boto3.InvalidDNSNameError is an exception type
boto3.InvalidS3AddressingStyleError is an exception type
boto3.InvalidRetryConfigurationError is an exception type
boto3.InvalidMaxRetryAttemptsError is an exception type
boto3.StubResponseError is an exception type
boto3.StubAssertionError is an exception type
boto3.UnStubbedResponseError is an exception type
boto3.InvalidConfigError is an exception type
boto3.InfiniteLoopConfigError is an exception type
boto3.RefreshWithMFAUnsupportedError is an exception type
boto3.MD5UnavailableError is an exception type
boto3.MetadataRetrievalError is an exception type
boto3.UndefinedModelAttributeError is an exception type
boto3.MissingServiceIdError is an exception type
Boto3Error.
import boto3 s3_client=boto3.client('s3') s3_client.exceptions.blah. blah is not an attribute, so it will error and list all the valid exceptions.
Just an update to the 'no exceptions on resources' problem as pointed to by @jarmod (do please feel free to update your answer if below seems applicable)
I have tested the below code and it runs fine. It uses 'resources' for doing things, but catches the client.exceptions - although it 'looks' somewhat wrong... it tests good, the exception classes are showing and matching when looked into using debugger at exception time...
It may not be applicable to all resources and clients, but works for data folders (aka s3 buckets).
lab_session = boto3.Session()
c = lab_session.client('s3') #this client is only for exception catching
try:
b = s3.Bucket(bucket)
b.delete()
except c.exceptions.NoSuchBucket as e:
#ignoring no such bucket exceptions
logger.debug("Failed deleting bucket. Continuing. {}".format(e))
except Exception as e:
#logging all the others as warning
logger.warning("Failed deleting bucket. Continuing. {}".format(e))
Hope this helps...
s3.meta.client.exceptions.NoSuchBucket
s3 is the service resource, e.g. s3 = boto3.resource('s3'). Works also for the actual resources, such as buckets: boto3.resource('s3').Bucket('bucket-name').meta.client.exceptions. ...
As a few others already mentioned, you can catch certain errors using the service client (service_client.exceptions.<ExceptionClass>) or resource (service_resource.meta.client.exceptions.<ExceptionClass>), however it is not well documented (also which exceptions belong to which clients). So here is how to get the complete mapping at time of writing (January 2020) in region EU (Ireland) (eu-west-1):
import boto3, pprint
region_name = 'eu-west-1'
session = boto3.Session(region_name=region_name)
exceptions = {
service: list(boto3.client(service).exceptions._code_to_exception)
for service in session.get_available_services()
}
pprint.pprint(exceptions, width=20000)
Here is a subset of the pretty large document:
{'acm': ['InvalidArnException', 'InvalidDomainValidationOptionsException', 'InvalidStateException', 'InvalidTagException', 'LimitExceededException', 'RequestInProgressException', 'ResourceInUseException', 'ResourceNotFoundException', 'TooManyTagsException'],
'apigateway': ['BadRequestException', 'ConflictException', 'LimitExceededException', 'NotFoundException', 'ServiceUnavailableException', 'TooManyRequestsException', 'UnauthorizedException'],
'athena': ['InternalServerException', 'InvalidRequestException', 'TooManyRequestsException'],
'autoscaling': ['AlreadyExists', 'InvalidNextToken', 'LimitExceeded', 'ResourceContention', 'ResourceInUse', 'ScalingActivityInProgress', 'ServiceLinkedRoleFailure'],
'cloudformation': ['AlreadyExistsException', 'ChangeSetNotFound', 'CreatedButModifiedException', 'InsufficientCapabilitiesException', 'InvalidChangeSetStatus', 'InvalidOperationException', 'LimitExceededException', 'NameAlreadyExistsException', 'OperationIdAlreadyExistsException', 'OperationInProgressException', 'OperationNotFoundException', 'StackInstanceNotFoundException', 'StackSetNotEmptyException', 'StackSetNotFoundException', 'StaleRequestException', 'TokenAlreadyExistsException'],
'cloudfront': ['AccessDenied', 'BatchTooLarge', 'CNAMEAlreadyExists', 'CannotChangeImmutablePublicKeyFields', 'CloudFrontOriginAccessIdentityAlreadyExists', 'CloudFrontOriginAccessIdentityInUse', 'DistributionAlreadyExists', 'DistributionNotDisabled', 'FieldLevelEncryptionConfigAlreadyExists', 'FieldLevelEncryptionConfigInUse', 'FieldLevelEncryptionProfileAlreadyExists', 'FieldLevelEncryptionProfileInUse', 'FieldLevelEncryptionProfileSizeExceeded', 'IllegalFieldLevelEncryptionConfigAssociationWithCacheBehavior', 'IllegalUpdate', 'InconsistentQuantities', 'InvalidArgument', 'InvalidDefaultRootObject', 'InvalidErrorCode', 'InvalidForwardCookies', 'InvalidGeoRestrictionParameter', 'InvalidHeadersForS3Origin', 'InvalidIfMatchVersion', 'InvalidLambdaFunctionAssociation', 'InvalidLocationCode', 'InvalidMinimumProtocolVersion', 'InvalidOrigin', 'InvalidOriginAccessIdentity', 'InvalidOriginKeepaliveTimeout', 'InvalidOriginReadTimeout', 'InvalidProtocolSettings', 'InvalidQueryStringParameters', 'InvalidRelativePath', 'InvalidRequiredProtocol', 'InvalidResponseCode', 'InvalidTTLOrder', 'InvalidTagging', 'InvalidViewerCertificate', 'InvalidWebACLId', 'MissingBody', 'NoSuchCloudFrontOriginAccessIdentity', 'NoSuchDistribution', 'NoSuchFieldLevelEncryptionConfig', 'NoSuchFieldLevelEncryptionProfile', 'NoSuchInvalidation', 'NoSuchOrigin', 'NoSuchPublicKey', 'NoSuchResource', 'NoSuchStreamingDistribution', 'PreconditionFailed', 'PublicKeyAlreadyExists', 'PublicKeyInUse', 'QueryArgProfileEmpty', 'StreamingDistributionAlreadyExists', 'StreamingDistributionNotDisabled', 'TooManyCacheBehaviors', 'TooManyCertificates', 'TooManyCloudFrontOriginAccessIdentities', 'TooManyCookieNamesInWhiteList', 'TooManyDistributionCNAMEs', 'TooManyDistributions', 'TooManyDistributionsAssociatedToFieldLevelEncryptionConfig', 'TooManyDistributionsWithLambdaAssociations', 'TooManyFieldLevelEncryptionConfigs', 'TooManyFieldLevelEncryptionContentTypeProfiles', 'TooManyFieldLevelEncryptionEncryptionEntities', 'TooManyFieldLevelEncryptionFieldPatterns', 'TooManyFieldLevelEncryptionProfiles', 'TooManyFieldLevelEncryptionQueryArgProfiles', 'TooManyHeadersInForwardedValues', 'TooManyInvalidationsInProgress', 'TooManyLambdaFunctionAssociations', 'TooManyOriginCustomHeaders', 'TooManyOriginGroupsPerDistribution', 'TooManyOrigins', 'TooManyPublicKeys', 'TooManyQueryStringParameters', 'TooManyStreamingDistributionCNAMEs', 'TooManyStreamingDistributions', 'TooManyTrustedSigners', 'TrustedSignerDoesNotExist'],
'cloudtrail': ['CloudTrailARNInvalidException', 'CloudTrailAccessNotEnabledException', 'CloudWatchLogsDeliveryUnavailableException', 'InsufficientDependencyServiceAccessPermissionException', 'InsufficientEncryptionPolicyException', 'InsufficientS3BucketPolicyException', 'InsufficientSnsTopicPolicyException', 'InvalidCloudWatchLogsLogGroupArnException', 'InvalidCloudWatchLogsRoleArnException', 'InvalidEventSelectorsException', 'InvalidHomeRegionException', 'InvalidKmsKeyIdException', 'InvalidLookupAttributesException', 'InvalidMaxResultsException', 'InvalidNextTokenException', 'InvalidParameterCombinationException', 'InvalidS3BucketNameException', 'InvalidS3PrefixException', 'InvalidSnsTopicNameException', 'InvalidTagParameterException', 'InvalidTimeRangeException', 'InvalidTokenException', 'InvalidTrailNameException', 'KmsException', 'KmsKeyDisabledException', 'KmsKeyNotFoundException', 'MaximumNumberOfTrailsExceededException', 'NotOrganizationMasterAccountException', 'OperationNotPermittedException', 'OrganizationNotInAllFeaturesModeException', 'OrganizationsNotInUseException', 'ResourceNotFoundException', 'ResourceTypeNotSupportedException', 'S3BucketDoesNotExistException', 'TagsLimitExceededException', 'TrailAlreadyExistsException', 'TrailNotFoundException', 'TrailNotProvidedException', 'UnsupportedOperationException'],
'cloudwatch': ['InvalidParameterInput', 'ResourceNotFound', 'InternalServiceError', 'InvalidFormat', 'InvalidNextToken', 'InvalidParameterCombination', 'InvalidParameterValue', 'LimitExceeded', 'MissingParameter'],
'codebuild': ['AccountLimitExceededException', 'InvalidInputException', 'OAuthProviderException', 'ResourceAlreadyExistsException', 'ResourceNotFoundException'],
'config': ['InsufficientDeliveryPolicyException', 'InsufficientPermissionsException', 'InvalidConfigurationRecorderNameException', 'InvalidDeliveryChannelNameException', 'InvalidLimitException', 'InvalidNextTokenException', 'InvalidParameterValueException', 'InvalidRecordingGroupException', 'InvalidResultTokenException', 'InvalidRoleException', 'InvalidS3KeyPrefixException', 'InvalidSNSTopicARNException', 'InvalidTimeRangeException', 'LastDeliveryChannelDeleteFailedException', 'LimitExceededException', 'MaxNumberOfConfigRulesExceededException', 'MaxNumberOfConfigurationRecordersExceededException', 'MaxNumberOfDeliveryChannelsExceededException', 'MaxNumberOfRetentionConfigurationsExceededException', 'NoAvailableConfigurationRecorderException', 'NoAvailableDeliveryChannelException', 'NoAvailableOrganizationException', 'NoRunningConfigurationRecorderException', 'NoSuchBucketException', 'NoSuchConfigRuleException', 'NoSuchConfigurationAggregatorException', 'NoSuchConfigurationRecorderException', 'NoSuchDeliveryChannelException', 'NoSuchRetentionConfigurationException', 'OrganizationAccessDeniedException', 'OrganizationAllFeaturesNotEnabledException', 'OversizedConfigurationItemException', 'ResourceInUseException', 'ResourceNotDiscoveredException', 'ValidationException'],
'dynamodb': ['BackupInUseException', 'BackupNotFoundException', 'ConditionalCheckFailedException', 'ContinuousBackupsUnavailableException', 'GlobalTableAlreadyExistsException', 'GlobalTableNotFoundException', 'IdempotentParameterMismatchException', 'IndexNotFoundException', 'InternalServerError', 'InvalidRestoreTimeException', 'ItemCollectionSizeLimitExceededException', 'LimitExceededException', 'PointInTimeRecoveryUnavailableException', 'ProvisionedThroughputExceededException', 'ReplicaAlreadyExistsException', 'ReplicaNotFoundException', 'RequestLimitExceeded', 'ResourceInUseException', 'ResourceNotFoundException', 'TableAlreadyExistsException', 'TableInUseException', 'TableNotFoundException', 'TransactionCanceledException', 'TransactionConflictException', 'TransactionInProgressException'],
'ec2': [],
'ecr': ['EmptyUploadException', 'ImageAlreadyExistsException', 'ImageNotFoundException', 'InvalidLayerException', 'InvalidLayerPartException', 'InvalidParameterException', 'InvalidTagParameterException', 'LayerAlreadyExistsException', 'LayerInaccessibleException', 'LayerPartTooSmallException', 'LayersNotFoundException', 'LifecyclePolicyNotFoundException', 'LifecyclePolicyPreviewInProgressException', 'LifecyclePolicyPreviewNotFoundException', 'LimitExceededException', 'RepositoryAlreadyExistsException', 'RepositoryNotEmptyException', 'RepositoryNotFoundException', 'RepositoryPolicyNotFoundException', 'ServerException', 'TooManyTagsException', 'UploadNotFoundException'],
'ecs': ['AccessDeniedException', 'AttributeLimitExceededException', 'BlockedException', 'ClientException', 'ClusterContainsContainerInstancesException', 'ClusterContainsServicesException', 'ClusterContainsTasksException', 'ClusterNotFoundException', 'InvalidParameterException', 'MissingVersionException', 'NoUpdateAvailableException', 'PlatformTaskDefinitionIncompatibilityException', 'PlatformUnknownException', 'ResourceNotFoundException', 'ServerException', 'ServiceNotActiveException', 'ServiceNotFoundException', 'TargetNotFoundException', 'UnsupportedFeatureException', 'UpdateInProgressException'],
'efs': ['BadRequest', 'DependencyTimeout', 'FileSystemAlreadyExists', 'FileSystemInUse', 'FileSystemLimitExceeded', 'FileSystemNotFound', 'IncorrectFileSystemLifeCycleState', 'IncorrectMountTargetState', 'InsufficientThroughputCapacity', 'InternalServerError', 'IpAddressInUse', 'MountTargetConflict', 'MountTargetNotFound', 'NetworkInterfaceLimitExceeded', 'NoFreeAddressesInSubnet', 'SecurityGroupLimitExceeded', 'SecurityGroupNotFound', 'SubnetNotFound', 'ThroughputLimitExceeded', 'TooManyRequests', 'UnsupportedAvailabilityZone'],
'eks': ['ClientException', 'InvalidParameterException', 'InvalidRequestException', 'ResourceInUseException', 'ResourceLimitExceededException', 'ResourceNotFoundException', 'ServerException', 'ServiceUnavailableException', 'UnsupportedAvailabilityZoneException'],
'elasticache': ['APICallRateForCustomerExceeded', 'AuthorizationAlreadyExists', 'AuthorizationNotFound', 'CacheClusterAlreadyExists', 'CacheClusterNotFound', 'CacheParameterGroupAlreadyExists', 'CacheParameterGroupNotFound', 'CacheParameterGroupQuotaExceeded', 'CacheSecurityGroupAlreadyExists', 'CacheSecurityGroupNotFound', 'QuotaExceeded.CacheSecurityGroup', 'CacheSubnetGroupAlreadyExists', 'CacheSubnetGroupInUse', 'CacheSubnetGroupNotFoundFault', 'CacheSubnetGroupQuotaExceeded', 'CacheSubnetQuotaExceededFault', 'ClusterQuotaForCustomerExceeded', 'InsufficientCacheClusterCapacity', 'InvalidARN', 'InvalidCacheClusterState', 'InvalidCacheParameterGroupState', 'InvalidCacheSecurityGroupState', 'InvalidParameterCombination', 'InvalidParameterValue', 'InvalidReplicationGroupState', 'InvalidSnapshotState', 'InvalidSubnet', 'InvalidVPCNetworkStateFault', 'NoOperationFault', 'NodeGroupNotFoundFault', 'NodeGroupsPerReplicationGroupQuotaExceeded', 'NodeQuotaForClusterExceeded', 'NodeQuotaForCustomerExceeded', 'ReplicationGroupAlreadyExists', 'ReplicationGroupNotFoundFault', 'ReservedCacheNodeAlreadyExists', 'ReservedCacheNodeNotFound', 'ReservedCacheNodeQuotaExceeded', 'ReservedCacheNodesOfferingNotFound', 'ServiceLinkedRoleNotFoundFault', 'SnapshotAlreadyExistsFault', 'SnapshotFeatureNotSupportedFault', 'SnapshotNotFoundFault', 'SnapshotQuotaExceededFault', 'SubnetInUse', 'TagNotFound', 'TagQuotaPerResourceExceeded', 'TestFailoverNotAvailableFault'],
'elasticbeanstalk': ['CodeBuildNotInServiceRegionException', 'ElasticBeanstalkServiceException', 'InsufficientPrivilegesException', 'InvalidRequestException', 'ManagedActionInvalidStateException', 'OperationInProgressFailure', 'PlatformVersionStillReferencedException', 'ResourceNotFoundException', 'ResourceTypeNotSupportedException', 'S3LocationNotInServiceRegionException', 'S3SubscriptionRequiredException', 'SourceBundleDeletionFailure', 'TooManyApplicationVersionsException', 'TooManyApplicationsException', 'TooManyBucketsException', 'TooManyConfigurationTemplatesException', 'TooManyEnvironmentsException', 'TooManyPlatformsException', 'TooManyTagsException'],
'elb': ['LoadBalancerNotFound', 'CertificateNotFound', 'DependencyThrottle', 'DuplicateLoadBalancerName', 'DuplicateListener', 'DuplicatePolicyName', 'DuplicateTagKeys', 'InvalidConfigurationRequest', 'InvalidInstance', 'InvalidScheme', 'InvalidSecurityGroup', 'InvalidSubnet', 'ListenerNotFound', 'LoadBalancerAttributeNotFound', 'OperationNotPermitted', 'PolicyNotFound', 'PolicyTypeNotFound', 'SubnetNotFound', 'TooManyLoadBalancers', 'TooManyPolicies', 'TooManyTags', 'UnsupportedProtocol'],
'emr': ['InternalServerError', 'InternalServerException', 'InvalidRequestException'],
'es': ['BaseException', 'DisabledOperationException', 'InternalException', 'InvalidTypeException', 'LimitExceededException', 'ResourceAlreadyExistsException', 'ResourceNotFoundException', 'ValidationException'],
'events': ['ConcurrentModificationException', 'InternalException', 'InvalidEventPatternException', 'LimitExceededException', 'ManagedRuleException', 'PolicyLengthExceededException', 'ResourceNotFoundException'],
'firehose': ['ConcurrentModificationException', 'InvalidArgumentException', 'LimitExceededException', 'ResourceInUseException', 'ResourceNotFoundException', 'ServiceUnavailableException'],
'glacier': ['InsufficientCapacityException', 'InvalidParameterValueException', 'LimitExceededException', 'MissingParameterValueException', 'PolicyEnforcedException', 'RequestTimeoutException', 'ResourceNotFoundException', 'ServiceUnavailableException'],
'glue': ['AccessDeniedException', 'AlreadyExistsException', 'ConcurrentModificationException', 'ConcurrentRunsExceededException', 'ConditionCheckFailureException', 'CrawlerNotRunningException', 'CrawlerRunningException', 'CrawlerStoppingException', 'EntityNotFoundException', 'GlueEncryptionException', 'IdempotentParameterMismatchException', 'InternalServiceException', 'InvalidInputException', 'NoScheduleException', 'OperationTimeoutException', 'ResourceNumberLimitExceededException', 'SchedulerNotRunningException', 'SchedulerRunningException', 'SchedulerTransitioningException', 'ValidationException', 'VersionMismatchException'],
'iam': ['ConcurrentModification', 'ReportExpired', 'ReportNotPresent', 'ReportInProgress', 'DeleteConflict', 'DuplicateCertificate', 'DuplicateSSHPublicKey', 'EntityAlreadyExists', 'EntityTemporarilyUnmodifiable', 'InvalidAuthenticationCode', 'InvalidCertificate', 'InvalidInput', 'InvalidPublicKey', 'InvalidUserType', 'KeyPairMismatch', 'LimitExceeded', 'MalformedCertificate', 'MalformedPolicyDocument', 'NoSuchEntity', 'PasswordPolicyViolation', 'PolicyEvaluation', 'PolicyNotAttachable', 'ServiceFailure', 'NotSupportedService', 'UnmodifiableEntity', 'UnrecognizedPublicKeyEncoding'],
'kinesis': ['ExpiredIteratorException', 'ExpiredNextTokenException', 'InternalFailureException', 'InvalidArgumentException', 'KMSAccessDeniedException', 'KMSDisabledException', 'KMSInvalidStateException', 'KMSNotFoundException', 'KMSOptInRequired', 'KMSThrottlingException', 'LimitExceededException', 'ProvisionedThroughputExceededException', 'ResourceInUseException', 'ResourceNotFoundException'],
'kms': ['AlreadyExistsException', 'CloudHsmClusterInUseException', 'CloudHsmClusterInvalidConfigurationException', 'CloudHsmClusterNotActiveException', 'CloudHsmClusterNotFoundException', 'CloudHsmClusterNotRelatedException', 'CustomKeyStoreHasCMKsException', 'CustomKeyStoreInvalidStateException', 'CustomKeyStoreNameInUseException', 'CustomKeyStoreNotFoundException', 'DependencyTimeoutException', 'DisabledException', 'ExpiredImportTokenException', 'IncorrectKeyMaterialException', 'IncorrectTrustAnchorException', 'InvalidAliasNameException', 'InvalidArnException', 'InvalidCiphertextException', 'InvalidGrantIdException', 'InvalidGrantTokenException', 'InvalidImportTokenException', 'InvalidKeyUsageException', 'InvalidMarkerException', 'KMSInternalException', 'KMSInvalidStateException', 'KeyUnavailableException', 'LimitExceededException', 'MalformedPolicyDocumentException', 'NotFoundException', 'TagException', 'UnsupportedOperationException'],
'lambda': ['CodeStorageExceededException', 'EC2AccessDeniedException', 'EC2ThrottledException', 'EC2UnexpectedException', 'ENILimitReachedException', 'InvalidParameterValueException', 'InvalidRequestContentException', 'InvalidRuntimeException', 'InvalidSecurityGroupIDException', 'InvalidSubnetIDException', 'InvalidZipFileException', 'KMSAccessDeniedException', 'KMSDisabledException', 'KMSInvalidStateException', 'KMSNotFoundException', 'PolicyLengthExceededException', 'PreconditionFailedException', 'RequestTooLargeException', 'ResourceConflictException', 'ResourceInUseException', 'ResourceNotFoundException', 'ServiceException', 'SubnetIPAddressLimitReachedException', 'TooManyRequestsException', 'UnsupportedMediaTypeException'],
'logs': ['DataAlreadyAcceptedException', 'InvalidOperationException', 'InvalidParameterException', 'InvalidSequenceTokenException', 'LimitExceededException', 'MalformedQueryException', 'OperationAbortedException', 'ResourceAlreadyExistsException', 'ResourceNotFoundException', 'ServiceUnavailableException', 'UnrecognizedClientException'],
'neptune': ['AuthorizationNotFound', 'CertificateNotFound', 'DBClusterAlreadyExistsFault', 'DBClusterNotFoundFault', 'DBClusterParameterGroupNotFound', 'DBClusterQuotaExceededFault', 'DBClusterRoleAlreadyExists', 'DBClusterRoleNotFound', 'DBClusterRoleQuotaExceeded', 'DBClusterSnapshotAlreadyExistsFault', 'DBClusterSnapshotNotFoundFault', 'DBInstanceAlreadyExists', 'DBInstanceNotFound', 'DBParameterGroupAlreadyExists', 'DBParameterGroupNotFound', 'DBParameterGroupQuotaExceeded', 'DBSecurityGroupNotFound', 'DBSnapshotAlreadyExists', 'DBSnapshotNotFound', 'DBSubnetGroupAlreadyExists', 'DBSubnetGroupDoesNotCoverEnoughAZs', 'DBSubnetGroupNotFoundFault', 'DBSubnetGroupQuotaExceeded', 'DBSubnetQuotaExceededFault', 'DBUpgradeDependencyFailure', 'DomainNotFoundFault', 'EventSubscriptionQuotaExceeded', 'InstanceQuotaExceeded', 'InsufficientDBClusterCapacityFault', 'InsufficientDBInstanceCapacity', 'InsufficientStorageClusterCapacity', 'InvalidDBClusterSnapshotStateFault', 'InvalidDBClusterStateFault', 'InvalidDBInstanceState', 'InvalidDBParameterGroupState', 'InvalidDBSecurityGroupState', 'InvalidDBSnapshotState', 'InvalidDBSubnetGroupStateFault', 'InvalidDBSubnetStateFault', 'InvalidEventSubscriptionState', 'InvalidRestoreFault', 'InvalidSubnet', 'InvalidVPCNetworkStateFault', 'KMSKeyNotAccessibleFault', 'OptionGroupNotFoundFault', 'ProvisionedIopsNotAvailableInAZFault', 'ResourceNotFoundFault', 'SNSInvalidTopic', 'SNSNoAuthorization', 'SNSTopicArnNotFound', 'SharedSnapshotQuotaExceeded', 'SnapshotQuotaExceeded', 'SourceNotFound', 'StorageQuotaExceeded', 'StorageTypeNotSupported', 'SubnetAlreadyInUse', 'SubscriptionAlreadyExist', 'SubscriptionCategoryNotFound', 'SubscriptionNotFound'],
'rds': ['AuthorizationAlreadyExists', 'AuthorizationNotFound', 'AuthorizationQuotaExceeded', 'BackupPolicyNotFoundFault', 'CertificateNotFound', 'DBClusterAlreadyExistsFault', 'DBClusterBacktrackNotFoundFault', 'DBClusterEndpointAlreadyExistsFault', 'DBClusterEndpointNotFoundFault', 'DBClusterEndpointQuotaExceededFault', 'DBClusterNotFoundFault', 'DBClusterParameterGroupNotFound', 'DBClusterQuotaExceededFault', 'DBClusterRoleAlreadyExists', 'DBClusterRoleNotFound', 'DBClusterRoleQuotaExceeded', 'DBClusterSnapshotAlreadyExistsFault', 'DBClusterSnapshotNotFoundFault', 'DBInstanceAlreadyExists', 'DBInstanceAutomatedBackupNotFound', 'DBInstanceAutomatedBackupQuotaExceeded', 'DBInstanceNotFound', 'DBInstanceRoleAlreadyExists', 'DBInstanceRoleNotFound', 'DBInstanceRoleQuotaExceeded', 'DBLogFileNotFoundFault', 'DBParameterGroupAlreadyExists', 'DBParameterGroupNotFound', 'DBParameterGroupQuotaExceeded', 'DBSecurityGroupAlreadyExists', 'DBSecurityGroupNotFound', 'DBSecurityGroupNotSupported', 'QuotaExceeded.DBSecurityGroup', 'DBSnapshotAlreadyExists', 'DBSnapshotNotFound', 'DBSubnetGroupAlreadyExists', 'DBSubnetGroupDoesNotCoverEnoughAZs', 'DBSubnetGroupNotAllowedFault', 'DBSubnetGroupNotFoundFault', 'DBSubnetGroupQuotaExceeded', 'DBSubnetQuotaExceededFault', 'DBUpgradeDependencyFailure', 'DomainNotFoundFault', 'EventSubscriptionQuotaExceeded', 'GlobalClusterAlreadyExistsFault', 'GlobalClusterNotFoundFault', 'GlobalClusterQuotaExceededFault', 'InstanceQuotaExceeded', 'InsufficientDBClusterCapacityFault', 'InsufficientDBInstanceCapacity', 'InsufficientStorageClusterCapacity', 'InvalidDBClusterCapacityFault', 'InvalidDBClusterEndpointStateFault', 'InvalidDBClusterSnapshotStateFault', 'InvalidDBClusterStateFault', 'InvalidDBInstanceAutomatedBackupState', 'InvalidDBInstanceState', 'InvalidDBParameterGroupState', 'InvalidDBSecurityGroupState', 'InvalidDBSnapshotState', 'InvalidDBSubnetGroupFault', 'InvalidDBSubnetGroupStateFault', 'InvalidDBSubnetStateFault', 'InvalidEventSubscriptionState', 'InvalidGlobalClusterStateFault', 'InvalidOptionGroupStateFault', 'InvalidRestoreFault', 'InvalidS3BucketFault', 'InvalidSubnet', 'InvalidVPCNetworkStateFault', 'KMSKeyNotAccessibleFault', 'OptionGroupAlreadyExistsFault', 'OptionGroupNotFoundFault', 'OptionGroupQuotaExceededFault', 'PointInTimeRestoreNotEnabled', 'ProvisionedIopsNotAvailableInAZFault', 'ReservedDBInstanceAlreadyExists', 'ReservedDBInstanceNotFound', 'ReservedDBInstanceQuotaExceeded', 'ReservedDBInstancesOfferingNotFound', 'ResourceNotFoundFault', 'SNSInvalidTopic', 'SNSNoAuthorization', 'SNSTopicArnNotFound', 'SharedSnapshotQuotaExceeded', 'SnapshotQuotaExceeded', 'SourceNotFound', 'StorageQuotaExceeded', 'StorageTypeNotSupported', 'SubnetAlreadyInUse', 'SubscriptionAlreadyExist', 'SubscriptionCategoryNotFound', 'SubscriptionNotFound'],
'route53': ['ConcurrentModification', 'ConflictingDomainExists', 'ConflictingTypes', 'DelegationSetAlreadyCreated', 'DelegationSetAlreadyReusable', 'DelegationSetInUse', 'DelegationSetNotAvailable', 'DelegationSetNotReusable', 'HealthCheckAlreadyExists', 'HealthCheckInUse', 'HealthCheckVersionMismatch', 'HostedZoneAlreadyExists', 'HostedZoneNotEmpty', 'HostedZoneNotFound', 'HostedZoneNotPrivate', 'IncompatibleVersion', 'InsufficientCloudWatchLogsResourcePolicy', 'InvalidArgument', 'InvalidChangeBatch', 'InvalidDomainName', 'InvalidInput', 'InvalidPaginationToken', 'InvalidTrafficPolicyDocument', 'InvalidVPCId', 'LastVPCAssociation', 'LimitsExceeded', 'NoSuchChange', 'NoSuchCloudWatchLogsLogGroup', 'NoSuchDelegationSet', 'NoSuchGeoLocation', 'NoSuchHealthCheck', 'NoSuchHostedZone', 'NoSuchQueryLoggingConfig', 'NoSuchTrafficPolicy', 'NoSuchTrafficPolicyInstance', 'NotAuthorizedException', 'PriorRequestNotComplete', 'PublicZoneVPCAssociation', 'QueryLoggingConfigAlreadyExists', 'ThrottlingException', 'TooManyHealthChecks', 'TooManyHostedZones', 'TooManyTrafficPolicies', 'TooManyTrafficPolicyInstances', 'TooManyTrafficPolicyVersionsForCurrentPolicy', 'TooManyVPCAssociationAuthorizations', 'TrafficPolicyAlreadyExists', 'TrafficPolicyInUse', 'TrafficPolicyInstanceAlreadyExists', 'VPCAssociationAuthorizationNotFound', 'VPCAssociationNotFound'],
's3': ['BucketAlreadyExists', 'BucketAlreadyOwnedByYou', 'NoSuchBucket', 'NoSuchKey', 'NoSuchUpload', 'ObjectAlreadyInActiveTierError', 'ObjectNotInActiveTierError'],
'sagemaker': ['ResourceInUse', 'ResourceLimitExceeded', 'ResourceNotFound'],
'secretsmanager': ['DecryptionFailure', 'EncryptionFailure', 'InternalServiceError', 'InvalidNextTokenException', 'InvalidParameterException', 'InvalidRequestException', 'LimitExceededException', 'MalformedPolicyDocumentException', 'PreconditionNotMetException', 'ResourceExistsException', 'ResourceNotFoundException'],
'ses': ['AccountSendingPausedException', 'AlreadyExists', 'CannotDelete', 'ConfigurationSetAlreadyExists', 'ConfigurationSetDoesNotExist', 'ConfigurationSetSendingPausedException', 'CustomVerificationEmailInvalidContent', 'CustomVerificationEmailTemplateAlreadyExists', 'CustomVerificationEmailTemplateDoesNotExist', 'EventDestinationAlreadyExists', 'EventDestinationDoesNotExist', 'FromEmailAddressNotVerified', 'InvalidCloudWatchDestination', 'InvalidConfigurationSet', 'InvalidFirehoseDestination', 'InvalidLambdaFunction', 'InvalidPolicy', 'InvalidRenderingParameter', 'InvalidS3Configuration', 'InvalidSNSDestination', 'InvalidSnsTopic', 'InvalidTemplate', 'InvalidTrackingOptions', 'LimitExceeded', 'MailFromDomainNotVerifiedException', 'MessageRejected', 'MissingRenderingAttribute', 'ProductionAccessNotGranted', 'RuleDoesNotExist', 'RuleSetDoesNotExist', 'TemplateDoesNotExist', 'TrackingOptionsAlreadyExistsException', 'TrackingOptionsDoesNotExistException'],
'sns': ['AuthorizationError', 'EndpointDisabled', 'FilterPolicyLimitExceeded', 'InternalError', 'InvalidParameter', 'ParameterValueInvalid', 'InvalidSecurity', 'KMSAccessDenied', 'KMSDisabled', 'KMSInvalidState', 'KMSNotFound', 'KMSOptInRequired', 'KMSThrottling', 'NotFound', 'PlatformApplicationDisabled', 'SubscriptionLimitExceeded', 'Throttled', 'TopicLimitExceeded'],
'sqs': ['AWS.SimpleQueueService.BatchEntryIdsNotDistinct', 'AWS.SimpleQueueService.BatchRequestTooLong', 'AWS.SimpleQueueService.EmptyBatchRequest', 'InvalidAttributeName', 'AWS.SimpleQueueService.InvalidBatchEntryId', 'InvalidIdFormat', 'InvalidMessageContents', 'AWS.SimpleQueueService.MessageNotInflight', 'OverLimit', 'AWS.SimpleQueueService.PurgeQueueInProgress', 'AWS.SimpleQueueService.QueueDeletedRecently', 'AWS.SimpleQueueService.NonExistentQueue', 'QueueAlreadyExists', 'ReceiptHandleIsInvalid', 'AWS.SimpleQueueService.TooManyEntriesInBatchRequest', 'AWS.SimpleQueueService.UnsupportedOperation'],
'ssm': ['AlreadyExistsException', 'AssociatedInstances', 'AssociationAlreadyExists', 'AssociationDoesNotExist', 'AssociationExecutionDoesNotExist', 'AssociationLimitExceeded', 'AssociationVersionLimitExceeded', 'AutomationDefinitionNotFoundException', 'AutomationDefinitionVersionNotFoundException', 'AutomationExecutionLimitExceededException', 'AutomationExecutionNotFoundException', 'AutomationStepNotFoundException', 'ComplianceTypeCountLimitExceededException', 'CustomSchemaCountLimitExceededException', 'DocumentAlreadyExists', 'DocumentLimitExceeded', 'DocumentPermissionLimit', 'DocumentVersionLimitExceeded', 'DoesNotExistException', 'DuplicateDocumentContent', 'DuplicateDocumentVersionName', 'DuplicateInstanceId', 'FeatureNotAvailableException', 'HierarchyLevelLimitExceededException', 'HierarchyTypeMismatchException', 'IdempotentParameterMismatch', 'InternalServerError', 'InvalidActivation', 'InvalidActivationId', 'InvalidAggregatorException', 'InvalidAllowedPatternException', 'InvalidAssociation', 'InvalidAssociationVersion', 'InvalidAutomationExecutionParametersException', 'InvalidAutomationSignalException', 'InvalidAutomationStatusUpdateException', 'InvalidCommandId', 'InvalidDeleteInventoryParametersException', 'InvalidDeletionIdException', 'InvalidDocument', 'InvalidDocumentContent', 'InvalidDocumentOperation', 'InvalidDocumentSchemaVersion', 'InvalidDocumentVersion', 'InvalidFilter', 'InvalidFilterKey', 'InvalidFilterOption', 'InvalidFilterValue', 'InvalidInstanceId', 'InvalidInstanceInformationFilterValue', 'InvalidInventoryGroupException', 'InvalidInventoryItemContextException', 'InvalidInventoryRequestException', 'InvalidItemContentException', 'InvalidKeyId', 'InvalidNextToken', 'InvalidNotificationConfig', 'InvalidOptionException', 'InvalidOutputFolder', 'InvalidOutputLocation', 'InvalidParameters', 'InvalidPermissionType', 'InvalidPluginName', 'InvalidResourceId', 'InvalidResourceType', 'InvalidResultAttributeException', 'InvalidRole', 'InvalidSchedule', 'InvalidTarget', 'InvalidTypeNameException', 'InvalidUpdate', 'InvocationDoesNotExist', 'ItemContentMismatchException', 'ItemSizeLimitExceededException', 'MaxDocumentSizeExceeded', 'ParameterAlreadyExists', 'ParameterLimitExceeded', 'ParameterMaxVersionLimitExceeded', 'ParameterNotFound', 'ParameterPatternMismatchException', 'ParameterVersionLabelLimitExceeded', 'ParameterVersionNotFound', 'ResourceDataSyncAlreadyExistsException', 'ResourceDataSyncCountExceededException', 'ResourceDataSyncInvalidConfigurationException', 'ResourceDataSyncNotFoundException', 'ResourceInUseException', 'ResourceLimitExceededException', 'StatusUnchanged', 'SubTypeCountLimitExceededException', 'TargetInUseException', 'TargetNotConnected', 'TooManyTagsError', 'TooManyUpdates', 'TotalSizeLimitExceededException', 'UnsupportedInventoryItemContextException', 'UnsupportedInventorySchemaVersionException', 'UnsupportedOperatingSystem', 'UnsupportedParameterType', 'UnsupportedPlatformType'],
'stepfunctions': ['ActivityDoesNotExist', 'ActivityLimitExceeded', 'ActivityWorkerLimitExceeded', 'ExecutionAlreadyExists', 'ExecutionDoesNotExist', 'ExecutionLimitExceeded', 'InvalidArn', 'InvalidDefinition', 'InvalidExecutionInput', 'InvalidName', 'InvalidOutput', 'InvalidToken', 'MissingRequiredParameter', 'ResourceNotFound', 'StateMachineAlreadyExists', 'StateMachineDeleting', 'StateMachineDoesNotExist', 'StateMachineLimitExceeded', 'TaskDoesNotExist', 'TaskTimedOut', 'TooManyTags'],
'sts': ['ExpiredTokenException', 'IDPCommunicationError', 'IDPRejectedClaim', 'InvalidAuthorizationMessageException', 'InvalidIdentityToken', 'MalformedPolicyDocument', 'PackedPolicyTooLarge', 'RegionDisabledException'],
'xray': ['InvalidRequestException', 'RuleLimitExceededException', 'ThrottledException']}
Only one import needed.
No if statement needed.
Use the client built-in exception as intended.
Ex:
from boto3 import client
cli = client('iam')
try:
cli.create_user(
UserName = 'Brian'
)
except cli.exceptions.EntityAlreadyExistsException:
pass
a CloudWatch example:
cli = client('logs')
try:
cli.create_log_group(
logGroupName = 'MyLogGroup'
)
except cli.exceptions.ResourceAlreadyExistsException:
pass
Or a comparison on the class name e.g.
except ClientError as e:
if 'EntityAlreadyExistsException' == e.__class__.__name__:
# handle specific error
Because they are dynamically created you can never import the class and catch it using real Python.
except Exception as e and then have if statements to determine the specific exception? How's that different from/better than catching specific exceptions? Its more lines, and you would need to import the library to get the class name anyway. Unless you wanna go with hardcoding the exception name. All in all, it seems like a bad way to go about it.
If you are calling the sign_up API (AWS Cognito) using Python3, you can use the following code.
def registerUser(userObj):
''' Registers the user to AWS Cognito.
'''
# Mobile number is not a mandatory field.
if(len(userObj['user_mob_no']) == 0):
mobilenumber = ''
else:
mobilenumber = userObj['user_country_code']+userObj['user_mob_no']
secretKey = bytes(settings.SOCIAL_AUTH_COGNITO_SECRET, 'latin-1')
clientId = settings.SOCIAL_AUTH_COGNITO_KEY
digest = hmac.new(secretKey,
msg=(userObj['user_name'] + clientId).encode('utf-8'),
digestmod=hashlib.sha256
).digest()
signature = base64.b64encode(digest).decode()
client = boto3.client('cognito-idp', region_name='eu-west-1' )
try:
response = client.sign_up(
ClientId=clientId,
Username=userObj['user_name'],
Password=userObj['password1'],
SecretHash=signature,
UserAttributes=[
{
'Name': 'given_name',
'Value': userObj['given_name']
},
{
'Name': 'family_name',
'Value': userObj['family_name']
},
{
'Name': 'email',
'Value': userObj['user_email']
},
{
'Name': 'phone_number',
'Value': mobilenumber
}
],
ValidationData=[
{
'Name': 'email',
'Value': userObj['user_email']
},
]
,
AnalyticsMetadata={
'AnalyticsEndpointId': 'string'
},
UserContextData={
'EncodedData': 'string'
}
)
except ClientError as error:
return {"errorcode": error.response['Error']['Code'],
"errormessage" : error.response['Error']['Message'] }
except Exception as e:
return {"errorcode": "Something went wrong. Try later or contact the admin" }
return {"success": "User registered successfully. "}
error.response['Error']['Code'] will be InvalidPasswordException, UsernameExistsException etc. So in the main function or where you are calling the function, you can write the logic to provide a meaningful message to the user.
An example for the response (error.response):
{
"Error": {
"Message": "Password did not conform with policy: Password must have symbol characters",
"Code": "InvalidPasswordException"
},
"ResponseMetadata": {
"RequestId": "c8a591d5-8c51-4af9-8fad-b38b270c3ca2",
"HTTPStatusCode": 400,
"HTTPHeaders": {
"date": "Wed, 17 Jul 2019 09:38:32 GMT",
"content-type": "application/x-amz-json-1.1",
"content-length": "124",
"connection": "keep-alive",
"x-amzn-requestid": "c8a591d5-8c51-4af9-8fad-b38b270c3ca2",
"x-amzn-errortype": "InvalidPasswordException:",
"x-amzn-errormessage": "Password did not conform with policy: Password must have symbol characters"
},
"RetryAttempts": 0
}
}
For further reference : https://boto3.amazonaws.com/v1/documentation/api/latest/reference/services/cognito-idp.html#CognitoIdentityProvider.Client.sign_up
Following @armod's update about exceptions being added right on client objects. I'll show how you can see all exceptions defined for your client class.
Exceptions are generated dynamically when you create your client with session.create_client() or boto3.client(). Internally it calls method botocore.errorfactory.ClientExceptionsFactory._create_client_exceptions() and fills client.exceptions field with constructed exception classes.
All class names are available in client.exceptions._code_to_exception dictionary, so you can list all types with following snippet:
client = boto3.client('s3')
for ex_code in client.exceptions._code_to_exception:
print(ex_code)
Hope it helps.
In case you have to deal with the arguably unfriendly logs client (CloudWatch Logs put-log-events), this is what I had to do to properly catch Boto3 client exceptions:
try:
### Boto3 client code here...
except boto_exceptions.ClientError as error:
Log.warning("Catched client error code %s",
error.response['Error']['Code'])
if error.response['Error']['Code'] in ["DataAlreadyAcceptedException",
"InvalidSequenceTokenException"]:
Log.debug(
"Fetching sequence_token from boto error response['Error']['Message'] %s",
error.response["Error"]["Message"])
# NOTE: apparently there's no sequenceToken attribute in the response so we have
# to parse response["Error"]["Message"] string
sequence_token = error.response["Error"]["Message"].split(":")[-1].strip(" ")
Log.debug("Setting sequence_token to %s", sequence_token)
This works both at first attempt (with empty LogStream) and subsequent ones.
You need to do something when it fails to handle the issue. Right now you are returning the actual exception. For example, if its not a problem that the user exists already and you want to use it as a get_or_create function maybe you handle the issue by returning the existing user object.
try:
user = iam_conn.create_user(UserName=username)
return user
except botocore.exceptions.ClientError as e:
#this exception could actually be other things other than exists, so you want to evaluate it further in your real code.
if e.message.startswith(
'enough of the exception message to identify it as the one you want')
print('that user already exists.')
user = iam_conn.get_user(UserName=username)
return user
elif e.message.some_other_condition:
#something else
else:
#unhandled ClientError
raise(e)
except SomeOtherExceptionTypeYouCareAbout as e:
#handle it
# any unhandled exception will raise here at this point.
# if you want a general handler
except Exception as e:
#handle it.
That said, maybe it is a problem for your app, in which case you want to want to put the exception handler around the code that called your create user function and let the calling function determine how to deal with it, for example, by asking the user to input another username, or whatever makes sense for your application.
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200in your check, as the return code could be a different2xxHTTP status code (e.g.,204when deleting a vault or archive,201when creating, etc.). At best, one should check for a non-4xx code (e.g.,statusCode < 400) but that's really brittle and I would not recommend it anyway: best to rely onbotothrowing exceptions at your code.