localstack s3 can't be accessed via boto3

Question

I am able to run localstack via docker and my docker-compose file looks like:

services:
  localstack:
    image: localstack/localstack:latest
    network_mode: host
    environment:
      - SERVICES=s3
      - AWS_DEFAULT_REGION=eu-west-1
      - HOSTNAME_EXTERNAL=localhost
      - DEBUG=1
    ports:
      - '4566-4583:4566-4583'

I am able to create bukcet, upload file via [awslocal][1] like:

create bukcet:

awslocal s3 mb s3://test
 > make_bucket: test

upload test file to s3

awslocal s3 cp test.txt s3://test
 > upload: ./test.txt to s3://test/test.txt

check if its uploaded:

awslocal s3 ls s3://test
 > 2022-12-25 22:18:44         10 test.txt

All I am trying next is to connect via a code. I wrote a simple boto3 python script and the code base is failing with Unable to locate credentials . I tried aws configure but considering I don't have any idea what is my access and secret key for localstack s3, it feels like a dead end. The python code base:

import boto3
from botocore.exceptions import ClientError

import os

ddb1 = boto3.client('s3', endpoint_url='http://localhost.localstack.cloud:4566')


def upload_file(file_name, bucket, object_name=None):
    """
    Upload a file to a S3 bucket.
    """
    try:
        if object_name is None:
            object_name = os.path.basename(file_name)
        response = ddb1.upload_file(
            file_name, bucket, object_name)
    except ClientError:
        print('Could not upload file to S3 bucket.')
        raise
    else:
        return response

upload_file("testdata/test.txt", "sample")

Any help on how to connect via code base without awslocal would be a nice help. [1]: https://github.com/localstack/awscli-local

Answer 1

Hi — I would implore you to update your docker-compose.yml file to this:

version: "3.8"

services:
  localstack:
    container_name: "${LOCALSTACK_DOCKER_NAME-localstack_main}"
    image: localstack/localstack
    ports:
      - "127.0.0.1:4566:4566"            # LocalStack Gateway
      - "127.0.0.1:4510-4559:4510-4559"  # external services port range
    environment:
      - DEBUG=${DEBUG-}
      - LAMBDA_EXECUTOR=${LAMBDA_EXECUTOR-}
      - DOCKER_HOST=unix:///var/run/docker.sock
    volumes:
      - "${LOCALSTACK_VOLUME_DIR:-./volume}:/var/lib/localstack"
      - "/var/run/docker.sock:/var/run/docker.sock"

The SERVICES configuration has been deprecated, and all services are lazily loaded right now. I have been able to test the script on my machine, after creating a bucket named sample , and with the above Compose file, it will work fine!