Python Boto3 put_object file from lambda in s3 - python-3.x

Question

I would like to send a json file in s3 from a lambda. I saw in the documentation that we can send with the function boto3 put_object a file or a bytes object (Body=b'bytes'|file).
But if I'm not wrong, if I send a file in s3 with Body=bytes and then I download my file the content will be not visible.
So in my lambda function, I receive messages from a SQS Queue, I created a file with the message content in the lambda temporary folder /tmp. And I want to get this json file to send it in my_bucket/folder/file.json
I saw many examples to create a file in s3 but Body parameter is in bytes and not a file.
This is my code (python3.7)
def alpaca_consent_customer_dev(event, context): # handler
# TODO implement
request_id = context.aws_request_id
print('START - RequestID: {}'.format(request_id))
# function to write json file
def write_json(target_path, target_file, data):
if not os.path.exists(target_path):
try:
os.makedirs(target_path)
except Exception as e:
print(e)
raise
with open(os.path.join(target_path, target_file), 'w') as f:
json.dump(data, f)
try:
s3 = boto3.client('s3', region_name="us-west-2")
request_id = context.aws_request_id
print('START - RequestID: {}'.format(request_id))
# Get message from SQS queue
for record in event['Records']:
data = record
# Get message from SQS
data_loaded = json.loads(data['body'])
sns_message_id = data_loaded['MessageId']
print('data loaded type:', type(data_loaded))
data_saved = json.dumps(data_loaded)
# Create json file in temporary folder
write_json('/tmp', sns_message_id+'.json', data_saved)
# Check if file exists
print(glob.glob("/tmp/*.json"))
# result: ['/tmp/3bb1c0bc-68d5-5c4d-b827-021301.json']
s3.put_object(Body='/tmp/'+sns_message_id + '.json', Bucket='mybucket', Key='my_sub_bucket/' + datetime.datetime.today().strftime('%Y%m%d')+ '/'+ sns_message_id + '.json')
except Exception as e:
raise Exception('ERROR lambda failed: {}'.format(str(e)))
Thanks for your help. Regards.

Answer 1

There's an official example in the boto3 docs:
import logging
import boto3
from botocore.exceptions import ClientError
def upload_file(file_name, bucket, object_name=None):
"""Upload a file to an S3 bucket
:param file_name: File to upload
:param bucket: Bucket to upload to
:param object_name: S3 object name. If not specified then file_name is used
:return: True if file was uploaded, else False
"""
# If S3 object_name was not specified, use file_name
if object_name is None:
object_name = file_name
# Upload the file
s3_client = boto3.client('s3')
try:
response = s3_client.upload_file(file_name, bucket, object_name)
except ClientError as e:
logging.error(e)
return False
return True
You can just use the upload_file method of the s3 client.