Method not available for boto3.client('transfer') in Lambda Python Function

Question

Hi,
I am unable to access the list_file_transfer_results method for the boto3.client('transfer') object.
After running the following code

```
s3 = boto3.client('s3')
transfer_client = boto3.client('transfer')

response = transfer_client.list_file_transfer_results(
ConnectorId='c-top-secret',
 TransferId=TransferId
 )
```
Receive the error of 'Transfer' object has no attribute 'list_file_transfer_results'

According to AWS documentation [https://boto3.amazonaws.com/v1/documentation/api/latest/reference/services/transfer/client/list_file_transfer_results.html]() it should exist.

Interestingly when running code to list all methods of the client object

```
print(dir(transfer_client))
```
it produces the following :

```
['_PY_TO_OP_NAME', '__class__', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattr__', '__getattribute__', '__getstate__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__le__', '__lt__', '__module__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', '_cache', '_client_config', '_convert_to_request_dict', '_emit_api_params', '_endpoint', '_exceptions', '_exceptions_factory', '_get_credentials', '_get_waiter_config', '_load_exceptions', '_loader', '_make_api_call', '_make_request', '_register_handlers', '_request_signer', '_resolve_endpoint_ruleset', '_response_parser', '_ruleset_resolver', '_serializer', '_service_model', '_user_agent_creator', 'can_paginate', 'close', 'create_access', 'create_agreement', 'create_connector', 'create_profile', 'create_server', 'create_user', 'create_workflow', 'delete_access', 'delete_agreement', 'delete_certificate', 'delete_connector', 'delete_host_key', 'delete_profile', 'delete_server', 'delete_ssh_public_key', 'delete_user', 'delete_workflow', 'describe_access', 'describe_agreement', 'describe_certificate', 'describe_connector', 'describe_execution', 'describe_host_key', 'describe_profile', 'describe_security_policy', 'describe_server', 'describe_user', 'describe_workflow', 'exceptions', 'generate_presigned_url', 'get_paginator', 'get_waiter', 'import_certificate', 'import_host_key', 'import_ssh_public_key', 'list_accesses', 'list_agreements', 'list_certificates', 'list_connectors', 'list_executions', 'list_host_keys', 'list_profiles', 'list_security_policies', 'list_servers', 'list_tags_for_resource', 'list_users', 'list_workflows', 'meta', 'send_workflow_step_state', 'start_directory_listing', 'start_file_transfer', 'start_server', 'stop_server', 'tag_resource', 'test_connection', 'test_identity_provider', 'untag_resource', 'update_access', 'update_agreement', 'update_certificate', 'update_connector', 'update_host_key', 'update_profile', 'update_server', 'update_user', 'waiter_names']
```
Notice that list_file_transfer_results is missing !

Possible conclusions:
* Running wrong version of Python (python_version = 3.12.7)
* Boto3 has this method removed for the ap-southeast-2 region
* The method has been depreciated, but AWS documentation not updated.

Any suggestions are warmly welcome!

Doan Vuong · Answer

I think you should using this method instead:
```
response = client.list_executions(
    MaxResults=123,
    NextToken='string',
    WorkflowId='string'
)
```
Here is response:
```
{
    'NextToken': 'string',
    'WorkflowId': 'string',
    'Executions': [
        {
            'ExecutionId': 'string',
            'InitialFileLocation': {
                'S3FileLocation': {
                    'Bucket': 'string',
                    'Key': 'string',
                    'VersionId': 'string',
                    'Etag': 'string'
                },
                'EfsFileLocation': {
                    'FileSystemId': 'string',
                    'Path': 'string'
                }
            },
            'ServiceMetadata': {
                'UserDetails': {
                    'UserName': 'string',
                    'ServerId': 'string',
                    'SessionId': 'string'
                }
            },
            'Status': 'IN_PROGRESS'|'COMPLETED'|'EXCEPTION'|'HANDLING_EXCEPTION'
        },
    ]
}
```

Refs: https://boto3.amazonaws.com/v1/documentation/api/1.35.6/reference/services/transfer/client/list_executions.html

re:Post Agent · Answer

The issue you're experiencing is likely due to an outdated version of the boto3 library in your Lambda function's environment. The `list_file_transfer_results` method is a relatively new addition to the AWS Transfer Family service, and it may not be available in older versions of boto3.

To resolve this, you should try the following steps:

1. Update the boto3 library in your Lambda function. You can do this by including the latest version of boto3 in your deployment package. Create a requirements.txt file with the following content:

```
   boto3==latest
   ```

Then, install the dependencies in a directory that you'll include in your Lambda deployment package:

```
   pip install -r requirements.txt -t ./package
   ```

2. Include the updated boto3 library in your Lambda deployment package along with your function code.

3. If you're using a Lambda layer for boto3, make sure it's updated to the latest version.

4. After updating boto3, redeploy your Lambda function.

It's important to note that AWS regularly updates their services and SDKs, and the documentation you're referring to might be for the latest version. Always ensure that your boto3 version is up-to-date to access the most recent features and methods.

If updating boto3 doesn't resolve the issue, you may want to double-check that the AWS Transfer Family service fully supports this method in your specific region (ap-southeast-2). Although it's unlikely, there could be regional differences in feature availability.

Lastly, make sure your IAM role for the Lambda function has the necessary permissions to use the AWS Transfer Family service and specifically the `list_file_transfer_results` action.

If the problem persists after trying these steps, you may want to contact AWS support for further assistance, as there could be an underlying issue specific to your account or setup.  
**Sources**  
[Working with AWS Boto3 - Amazon Braket](https://docs.aws.amazon.com/braket/latest/developerguide/braket-using-boto3.html)  
[Code examples for Lambda using AWS SDKs - AWS Lambda](https://docs.aws.amazon.com/lambda/latest/dg/service_code_examples.html)  
[AWS client not reused in a Lambda function | Amazon CodeGuru, Detector Library](https://docs.aws.amazon.com/codeguru/detector-library/python/lambda-client-reuse/index.html)

Method not available for boto3.client('transfer') in Lambda Python Function

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