IMI-Map Database Migration Tool

A tool for migrating the Postgres database of the old IMI-Map to a MongoDB for the imimap21

Usage

Prerequisites

First you'll have to decide how you want to use the resulting MongoDB. There are three options:

• Mount a local directory as volume for the MongoDB to write the database files to
• Export the database from the service when the conversion is done
• Reuse the volume used in the migration for the actual IMI-Map

Option 1: Directory mounting

Edit the docker-compose.yml and change the mapping for the volume mongo-data to your preferred directory. After migrating the database you can use the directory as a mounted volume for the database container of the new IMI-Map.

Option 2: Exporting the resulting database

1. Run the migration (see next section)
2. Connect to the Docker container using docker exec -it <container-name> bash
3. Run mongodump --archive=db-dump.gz --gzip --db=imimap inside the container to dump the database to /db-dump.gz
4. Exit the Docker container using exit
5. Fetch the archive from the Docker container using docker cp <container-name>:/db-dump.gz <local destination path>

Option 3: Reuse the volume

If you want to reuse the volume created by the migration for the new MongoDB, you can simply mount the volume mongo-data in the new IMI-Map's docker-compose.yml.

Run the migration

1. Put an SQL dump file of the old database into the init/ directory and start the Docker-Compose-Project using docker-compose up -d
2. Run the migration using npm run migrate
3. The Docker service db-mongo now contains the migrated database.

Project structure

The project consists of 5 different parts:

• The old Postgres-Models (src/pgModels)
• The new Mongoose-Models (src/mongooseModels), the new IMI-Map uses the same models
• Loaders for loading the Postgres entities from the old database (src/loaders)
• Converters for converting the Postgres entities to the new MongoDB entities (src/converters)
• Some helper functions and utility classes (src/helpers)

The index.ts executes the migration by loading the old models using the provided loaders and converting them to the new models using the converters.