catching exceptions from boto3

Question

I'm coding a script to upload data to s3 and I'm wondering how I know what exceptions to catch.  I've seen the documentation here (https://boto3.amazonaws.com/v1/documentation/api/latest/guide/error-handling.html), but now I'm getting an botocore.exceptions.EndpointConnectionError.  How do I know I am catching all the exceptions for boto3 that I need to catch?  Please don't tell me it's trial and error.

Accepted Answer

The [S3 API guide](https://docs.aws.amazon.com/AmazonS3/latest/API/ErrorResponses.html) provides all possible error responses thrown by the S3 service. Additionally, the Python package [aws-error-utils](https://github.com/benkehoe/aws-error-utils) can streamline some of the error handling in boto3.

Answer

You could try to catch ClientError and then parse the error response, for example,

```
import boto3, botocore.exceptions

s3 = boto3.client('s3')
try:
    s3.get_object(Bucket='some-bucket', Key='some key')
except botocore.exceptions.ClientError as error:
    if error.response['Error']['Code'] == 'NoSuchKey':
        print('No such object')
    else: # Unknown exception
        print(error.response)
```

catching exceptions from boto3

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