Initialization Hooks

Introduction

LocalStack for Snowflake supports automatically executing *.sf.sql files via Init Hooks when mounted into the Docker container. A script can be added to one of these stages in the lifecycle:

• BOOT: the container is running, but LocalStack hasn’t started
• START: the Python process is running, and LocalStack is starting
• READY: LocalStack is ready for requests
• SHUTDOWN: LocalStack is shutting down

A script can be in one of four states: UNKNOWN, RUNNING, SUCCESSFUL, or ERROR. By default, scripts are in the UNKNOWN state when first discovered.

Getting started

To begin, create a script called test.sf.sql with the following SQL statements:

CREATE DATABASE foobar123;
CREATE DATABASE test123;
SHOW DATABASES;

Mount the script into /etc/localstack/init/ready.d/ using Docker Compose or the localstack CLI:

• docker-compose.yml
• CLI

version: "3.8"

services:
  localstack:
    container_name: "${LOCALSTACK_DOCKER_NAME:-localstack-main}"
    image: localstack/snowflake
    ports:
      - "127.0.0.1:4566:4566"
      - "127.0.0.1:4510-4559:4510-4559"
      - "127.0.0.1:443:443"
    environment:
      - LOCALSTACK_AUTH_TOKEN=${LOCALSTACK_AUTH_TOKEN:?}
      - DEBUG=1
    volumes:
      - "/path/to/test.sf.sql:/etc/localstack/init/ready.d/test.sf.sql"  # ready hook
      - "${LOCALSTACK_VOLUME_DIR:-./volume}:/var/lib/localstack"
      - "/var/run/docker.sock:/var/run/docker.sock"

# DOCKER_FLAGS are additional parameters to the `docker run` command of localstack start

DOCKER_FLAGS='-v /path/to/test.sf.sql:/etc/localstack/init/ready.d/test.sf.sql' DEBUG=1 localstack start

Start the Snowflake emulator, and the following logs will appear:

DEBUG --- [et.reactor-0] s.analytics.handler        : REQ: POST /queries/v1/query-request {"sqlText": "CREATE DATABASE foobar123", ...
DEBUG --- [et.reactor-0] s.analytics.handler        : REQ: POST /queries/v1/query-request {"sqlText": "CREATE DATABASE test123", ...
DEBUG --- [et.reactor-0] s.analytics.handler        : REQ: POST /queries/v1/query-request {"sqlText": "SHOW DATABASES", ...