boto3 Archives - Page 2 of 2

How to write a Dictionary to JSON file in S3 Bucket using boto3 and Python

If you want to write a python dictionary to a JSON file in S3 then you can use the code examples below.

There are two code examples doing the same thing below because boto3 provides a client method and a resource method to edit and access AWS S3.

Writing Python Dictionary to an S3 Object using boto3 Client

import boto3
import json
from datetime import date

data_dict = {
    'Name': 'Daikon Retek',
    'Birthdate': date(2000, 4, 7),
    'Subjects': ['Math', 'Science', 'History']
}

# Convert Dictionary to JSON String
data_string = json.dumps(data_dict, indent=2, default=str)


# Upload JSON String to an S3 Object
client = boto3.client('s3')

client.put_object(
    Bucket='radishlogic-bucket', 
    Key='s3_folder/client_data.json',
    Body=data_string
)

How to download files from S3 Bucket using boto3 and Python

If you want to download a file from an AWS S3 Bucket using Python, then you can use the sample codes below.

The codes below use AWS SDK for Python named boto3.

boto3 provides three methods to download a file.

download_file()
download_fileobj() – with multipart upload
get_object()

Then for each method, you can use the client class or the resource class of boto3.

Both of the classes will be used for each of the methods above.

Note: All examples will work with any Python3 environment running in Windows, MacOS or Linux operating systems.

Convert boto3 AMI Creation Date from string to Python datetime

When retrieving the AMI Creation Date from boto3 it returns a string data type. Visually, this is okay but it is challenging to do operations and comparisons to the AMI Creation Date in this format.

To solve the issue we need to convert the AMI Creation Date from type string to datetime before we could do some operations.

The AMI Creation Date string looks like 2019-09-18T07:34:34.000Z. To convert this we need to use the strptime function from the datetime.datetime library.