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# Type of request: This is a ...

[x] bug report
[ ] feature request

# Detailed description

Using node.js AWS SDK function `getObject` returns object with `0` bytes using 4566 port. 
On port 4572 it works fine.

# Steps to reproduce

## Command used to start LocalStack

```
  localstack:
    image: localstack/localstack
    networks:
      - localstack-network
    ports:
      - 4566:4566
      - 4572:4572
      - 8080:8080
    environment:
      - DEBUG=1
      - HOSTNAME_EXTERNAL=localstack
      - SERVICES=sqs,lambda,cloudwatch,s3,iam,ec2,stepfunctions,cloudwatchlogs
      - LAMBDA_REMOTE_DOCKER=false
      - LAMBDA_EXECUTOR=docker
      - LAMBDA_DOCKER_NETWORK=localstack-network
      - AWS_ACCESS_KEY_ID=123
      - AWS_SECRET_ACCESS_KEY=xyz
      - DEFAULT_REGION=us-east-1
      - DOCKER_HOST=unix:///var/run/docker.sock
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock
      - /tmp/localstack:/tmp/localstack
```

## Client code (AWS SDK code snippet, or sequence of "awslocal" commands)

```
export const s3 = new AWS.S3({
  endpoint: `http://localhost:4566`,
  s3ForcePathStyle: true,
  sslEnabled: false
});

const { Body } = await s3.getObject({
 Bucket: 'bucket',
 Key: 'file.json'
}).promise();
```
""" Determine backend port based on custom rules. """
    
    if 'AWSAccessKeyId=' in path or 'Signature=' in path:
        return config.PORT_S3
    
    if is_sqs_queue_url(path):
        return config.PORT_SQS
    
    if path.startswith('/shell') or path.startswith('/dynamodb/shell'):
        return config.PORT_DYNAMODB
    data_bytes = to_bytes(data or '')
    if path == '/' and to_bytes('QueueName=') in data_bytes:
        return config.PORT_SQS
    
    stripped = path.strip('/')
    if method in ['GET', 'HEAD'] and '/' in stripped:
        
        return config.PORT_S3
    if stripped and '/' not in stripped:
        if method == 'PUT':
            
            return config.PORT_S3
        if method == 'POST' and is_s3_form_data(data_bytes):
            
            return config.PORT_S3
def get_service_port_for_account(service, headers):