如何处理boto3的错误？

使用异常中包含的响应。这是一个例子：

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)

异常中的响应字典将包含以下内容：

['Error']['Code'] 例如 'EntityAlreadyExists' 或 'ValidationError'

['ResponseMetadata']['HTTPStatusCode'] 例如 400

['ResponseMetadata']['RequestId'] 例如'd2b06652-88d7-11e5-99d0-812348583a35'

['Error']['Message'] 例如“发生错误（EntityAlreadyExists）......”

['错误']['类型'] 例如'发件人'

有关更多信息，请参阅：

boto3 错误处理

botocore 错误处理

[更新时间：2018-03-07]

AWS Python 开发工具包已开始在 clients（虽然不在 resources）上公开您可以显式捕获的服务异常，因此现在可以像这样编写该代码：

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)

不幸的是，目前没有关于这些错误/异常的文档，但您可以获得核心错误列表，如下所示：

import botocore
import boto3
[e for e in dir(botocore.exceptions) if e.endswith('Error')]

请注意，您必须同时导入 botocore 和 boto3。如果您只导入 botocore，您会发现 botocore 没有名为 exceptions 的属性。这是因为异常是由 boto3 动态填充到 botocore 中的。

您可以获得服务特定异常的列表，如下所示（根据需要将 iam 替换为相关服务）：

import boto3
iam = boto3.client('iam')
[e for e in dir(iam.exceptions) if e.endswith('Exception')]

[更新时间：2021-09-07]

除了前面提到的客户端异常方法外，还有一个名为 aws-error-utils 的第三方帮助程序包。

---

我发现它非常有用，因为没有记录 Exceptions 来列出这个包的屏幕上的所有异常。这是我用来做的代码：

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])

结果是：

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

---

只是对@jarmod 所指出的“资源无例外”问题的更新（如果下面似乎适用，请随时更新您的答案）

我已经测试了下面的代码，它运行良好。它使用“资源”来做事情，但捕获了 client.exceptions - 虽然它“看起来”有些错误......它测试良好，异常类在使用调试器时显示和匹配异常时间...

它可能不适用于所有资源和客户端，但适用于数据文件夹（又名 s3 存储桶）。

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))

希望这可以帮助...

---

正如其他一些已经提到的那样，您可以使用服务客户端 (service_client.exceptions.<ExceptionClass>) 或资源 (service_resource.meta.client.exceptions.<ExceptionClass>) 捕获某些错误，但是没有很好的文档记录（以及哪些异常属于哪些客户端）。因此，以下是如何在撰写本文时（2020 年 1 月）在欧盟地区（爱尔兰）（eu-west-1）获取完整映射：

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)

这是相当大的文档的一个子集：

{'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']}

---

只需要一次导入。

不需要 if 语句。

按预期使用客户端内置异常。

前任：

from boto3 import client

cli = client('iam')
try:
    cli.create_user(
        UserName = 'Brian'
    )
except cli.exceptions.EntityAlreadyExistsException:
    pass

CloudWatch 示例：

cli = client('logs')
try:
    cli.create_log_group(
        logGroupName = 'MyLogGroup'
    )
except cli.exceptions.ResourceAlreadyExistsException:
    pass

---

或者比较类名，例如

except ClientError as e:
    if 'EntityAlreadyExistsException' == e.__class__.__name__:
        # handle specific error

因为它们是动态创建的，所以您永远无法导入该类并使用真正的 Python 捕获它。

---

如果您使用 Python3 调用 sign_up API (AWS Cognito)，则可以使用以下代码。

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'] 将是 InvalidPasswordException、UsernameExistsException 等。因此，在主函数或调用函数的地方，您可以编写逻辑以向用户提供有意义的消息。

响应示例（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
  }
}

如需进一步参考：https://boto3.amazonaws.com/v1/documentation/api/latest/reference/services/cognito-idp.html#CognitoIdentityProvider.Client.sign_up

---

关注 @armod 关于在 client 对象上添加异常的更新。我将展示如何查看为您的客户端类定义的所有异常。

当您使用 session.create_client() 或 boto3.client() 创建客户端时，会动态生成异常。它在内部调用方法 botocore.errorfactory.ClientExceptionsFactory._create_client_exceptions() 并用构造的异常类填充 client.exceptions 字段。

client.exceptions._code_to_exception 字典中提供了所有类名，因此您可以使用以下代码段列出所有类型：

client = boto3.client('s3')

for ex_code in client.exceptions._code_to_exception:
    print(ex_code)

希望能帮助到你。

---

如果您必须处理可以说是不友好的 logs 客户端 (CloudWatch Logs put-log-events)，我必须这样做才能正确捕获 Boto3 客户端异常：

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)

这在第一次尝试（使用空 LogStream）和后续尝试时都有效。

---

当它无法处理问题时，您需要做一些事情。现在您正在返回实际的异常。例如，如果用户已经存在并且您想将其用作 get_or_create 函数不是问题，那么您可以通过返回现有用户对象来处理问题。

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.

也就是说，这可能是您的应用程序的问题，在这种情况下，您希望将异常处理程序放在调用您的 create user 函数的代码周围，并让调用函数确定如何处理它，例如，通过询问用户输入另一个用户名，或者对您的应用程序有意义的任何内容。

---