Script for docker compose and redis sentinel config generation

docker-compose-gen.py

import sys

REDIS_CONFIG_MASTER_NAME = "mymaster"

def generate_sentinels(num_pairs, num_sentinels):
    docker_compose = ""
    for i in range(1, num_sentinels + 1):
        docker_compose += f"  redis-sentinel-{i}:\n"
        docker_compose += f"    container_name: 'redis-sentinel-{i}'\n"
        docker_compose += f"    image: redis:6.0-alpine\n"
        docker_compose += f"    ports:\n"
        docker_compose += f"      - '{5000 + (i - 1)}:5000'\n"
        docker_compose += f"    command: redis-server /etc/sentinel/sentinel-{i}.conf --sentinel\n"
        docker_compose += f"    volumes:\n"
        docker_compose += f"      - ./config/sentinel:/etc/sentinel\n"
        if i == 1:
            docker_compose += f"    depends_on:\n"
            for j in range(1, num_pairs + 1):
                docker_compose += f"      - redis-master-{j}\n"
        else:
            docker_compose += f"    depends_on:\n"
            docker_compose += f"      - redis-sentinel-1\n"
        docker_compose += "\n"
    return docker_compose


def generate_sentinel_confs(num_pairs, num_sentinels):
    for i in range(1, num_sentinels + 1):
        sentinel_conf = generate_sentinel_conf(num_pairs)
        with open(f'config/sentinel/sentinel-{i}.conf', 'w') as file:
            file.write(sentinel_conf)


def generate_sentinel_conf(num_pairs):
    sentinel_conf = f"port 5000\n"
    for i in range(1, num_pairs + 1):
        sentinel_conf += f"sentinel monitor {REDIS_CONFIG_MASTER_NAME}-{i} redis-master-{i} 6379 2\n"
        sentinel_conf += f"sentinel down-after-milliseconds {REDIS_CONFIG_MASTER_NAME}-{i} 5000\n"
        sentinel_conf += f"sentinel failover-timeout {REDIS_CONFIG_MASTER_NAME}-{i} 60000\n"
        sentinel_conf += f"sentinel parallel-syncs {REDIS_CONFIG_MASTER_NAME}-{i} 1\n\n"

    return sentinel_conf


def generate_docker_compose(num_pairs, num_sentinels):
    docker_compose = f"version: '3'\n\nservices:\n"

    for i in range(1, num_pairs + 1):
        docker_compose += f"  redis-master-{i}:\n"
        docker_compose += f"    container_name: 'redis-master-{i}'\n"
        docker_compose += f"    image: redis:6.0-alpine\n"
        docker_compose += f"    command: redis-server\n"
        docker_compose += f"    ports:\n"
        docker_compose += f"      - '{(i - 1) * 2 + 6379}:6379'\n"

        docker_compose += f"  redis-slave-{i}:\n"
        docker_compose += f"    container_name: 'redis-slave-{i}'\n"
        docker_compose += f"    image: redis:6.0-alpine\n"
        docker_compose += f"    ports:\n"
        docker_compose += f"      - '{(i - 1) * 2 + 6380}:6379'\n"
        docker_compose += f"    command: redis-server --slaveof redis-master-{i} 6379\n"
        docker_compose += f"    depends_on:\n"
        docker_compose += f"      - redis-master-{i}\n\n"

    docker_compose += generate_sentinels(num_pairs, num_sentinels)

    return docker_compose


if __name__ == "__main__":
    if len(sys.argv) != 3:
        print("Usage: python docker-compose-gen.py <num_pairs> <num_sentinels>")
        sys.exit(1)

    num_pairs = int(sys.argv[1])
    num_sentinels = int(sys.argv[2])

    compose_content = generate_docker_compose(num_pairs, num_sentinels)
    generate_sentinel_confs(num_pairs, num_sentinels)

    with open('docker-compose.yml', 'w') as file:
        file.write(compose_content)