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Other Client settings

Content type guessing (content_type_method)

All of the clients support passing a content_type_method when they are instantiated.
This is a method that is used to guess the MIME (media) type (often called the "content type") of the file and set that on the cloud provider.

By default, content_type_method use the Python built-in guess_type to set this content type. This guesses based on the file extension, and may not always get the correct type. In these cases, you can set content_type_method to your own function that gets the proper type; for example, by reading the file content or by looking it up in a dictionary of filename-to-media-type mappings that you maintain.

If you set a custom method, it should follow the signature of guess_type and return a tuple of the form: (content_type, content_encoding); for example, ("text/css", None).

If you set content_type_method to None, it will do whatever the default of the cloud provider's SDK does. This varies from provider to provider.

Here is an example of using a custom content_type_method.

import mimetypes
from pathlib import Path

from cloudpathlib import S3Client, CloudPath

def my_content_type(path):
    # do lookup for content types I define; fallback to
    # guess_type for anything else
    return {
        ".potato": ("application/potato", None),
    }.get(Path(path).suffix, mimetypes.guess_type(path))

# create a client with my custom content type
client = S3Client(content_type_method=my_content_type)

# To use this same method for every cloud path, set our client as the default.
# This is optional, and you could use client.CloudPath to create paths instead.

# create a cloud path
cp1 = CloudPath("s3://cloudpathlib-test-bucket/i_am_a.potato")

# check content type with boto3
print(client.s3.Object(cp1.bucket, cp1.key).content_type)
#> application/potato