Generating Alembic Migration Configuration

This function uses the Alembic library to generate a migration configuration. It sets the migration directory, revision ID, and output file. The function first configures the Alembic configuration file, then creates a database engine, marks the current revision ID with the stamp method, and finally writes the generated migration script to the specified output file.

Technology Stack : Python, Alembic, SQLAlchemy

Code Type : Python Function

Code Difficulty : Intermediate

                
                    
import random
from alembic import command
from alembic.config import Config
from sqlalchemy import create_engine

def generate_migration_config(directory, revision_id, output):
    """
    Generate a migration configuration using Alembic.
    """
    # Set up the Alembic configuration
    config = Config()
    config.set_main_option('script_location', directory)
    config.set_main_option('sqlalchemy.url', 'sqlite:///example.db')

    # Create an engine to interact with the database
    engine = create_engine('sqlite:///example.db')

    # Generate the migration
    command.stamp(config, revision_id)

    # Write the migration to the output file
    with open(output, 'w') as f:
        command.generate(config, f)

# Usage example
generate_migration_config('migrations', 'head', 'new_migration.py')