How to read file from S3 bucket using boto3?

You can use the below script to read the content of a file from S3 bucket using boto3 and print the output to the command line.

Step 1: Install and configure boto3

https://cloudaffaire.com/how-to-install-python-boto3-sdk-for-aws/

https://cloudaffaire.com/how-to-configure-python-boto3-sdk-for-aws/

https://pypi.org/project/argparse/

Step 2: Create a script to print the content of an S3 object in the command line

## Create a python script to print content of an S3 object
cat << EOF > print_object.py
import argparse
import boto3
import json
from botocore.exceptions import ClientError

parser = argparse.ArgumentParser(description='Print content of an s3 object')
parser.add_argument('--bucket_name', type=str, help='The name of the bucket')
parser.add_argument('--key', type=str, help='file or folder path in S3')
args = parser.parse_args()
client = boto3.client('s3')

def print_object(bucket_name, key):
    try:
        data = client.get_object(Bucket=bucket_name, Key=key)
        contents = data['Body'].read()
        print(contents.decode("utf-8"))
    except ClientError as e:
        print(e)

bucket_name = args.bucket_name
key = args.key
print_object(bucket_name, key)
EOF

## Create a python script to print content of an S3 object

cat << EOF > print_object.py

import argparse

import boto3

import json

from botocore.exceptions import ClientError

parser = argparse.ArgumentParser(description='Print content of an s3 object')

parser.add_argument('--bucket_name', type=str, help='The name of the bucket')

parser.add_argument('--key', type=str, help='file or folder path in S3')

args = parser.parse_args()

client = boto3.client('s3')

def print_object(bucket_name, key):

try:

data = client.get_object(Bucket=bucket_name, Key=key)

contents = data['Body'].read()

print(contents.decode("utf-8"))

except ClientError as e:

print(e)

bucket_name = args.bucket_name

key = args.key

print_object(bucket_name, key)

EOF

Step 3: Execute the script to print a file contents hosted in an S3 bucket

## Execute the script 
python3 print_object.py --bucket_name cloudaffaire1 --key targetDir/targetFile

1 2	## Execute the script python3 print_object.py --bucket_name cloudaffaire1 --key targetDir/targetFile