Quickstart#

This repository contains the methods used to identify over 1.4 billion Creative Commons licensed works. The challenge is that these works are dispersed throughout the web and identifying them requires a combination of techniques.

Currently, we only pull data from APIs which serve Creative Commons licensed media. In the past, we have also used web crawl data as a source.

API Data#

Apache Airflow is used to manage the workflow for various API ETL jobs which pull and process data from a number of open APIs on the internet.

API Workflows#

To view more information about all the available workflows (DAGs) within the project, see DAGs.md.

See each provider API script’s notes in their respective handbook entry.

Development setup for Airflow and API puller scripts#

There are a number of scripts in the directory catalog/dags/provider_api_scripts eventually loaded into a database to be indexed for searching in the Openverse API. These run in a different environment than the PySpark portion of the project, and so have their own dependency requirements.

For instructions geared specifically towards production deployments, see DEPLOYMENT.md

Requirements#

You’ll need docker and docker-compose installed on your machine, with versions new enough to use version 3 of Docker Compose .yml files.

You will also need the just command runner installed.

Setup#

To set up the local python environment along with the pre-commit hook, run:

python3 -m venv venv
source venv/bin/activate
just catalog/install

The containers will be built when starting the stack up for the first time. If you’d like to build them prior to that, run:

just build

Environment#

To set up environment variables run:

just env

This will generate a .env file which is used by the containers.

The .env file is split into four sections:

  1. Airflow Settings - these can be used to tweak various Airflow properties

  2. API Keys - set these if you intend to test one of the provider APIs referenced

  3. Connection/Variable info - this will not likely need to be modified for local development, though the values will need to be changed in production

  4. Other config - misc. configuration settings, some of which are useful for local dev

The .env file does not need to be modified if you only want to run the tests.

Running & Testing#

There is a docker-compose.yml provided in the catalog directory, so from that directory, run

just catalog/up

This results, among other things, in the following running containers:

  • openverse_catalog_webserver_1

  • openverse_catalog_postgres_1

  • openverse_catalog_s3_1

and some networking setup so that they can communicate. Note:

  • openverse_catalog_webserver_1 is running the Apache Airflow daemon, and also has a few development tools (e.g., pytest) installed.

  • openverse_catalog_postgres_1 is running PostgreSQL, and is setup with some databases and tables to emulate the production environment. It also provides a database for Airflow to store its running state.

  • The directory containing all modules files (including DAGs, dependencies, and other tooling) will be mounted to the directory /opt/airflow/catalog in the container openverse_catalog_webserver_1. On production, only the DAGs folder will be mounted, e.g. /opt/airflow/openverse/dags.

The various services can be accessed using these links:

  • Airflow: localhost:9090 (The default username and password are both airflow.)

  • Minio Console: localhost:5011 (The default username and password are test_key and test_secret)

  • Postgres: localhost:5434 (using a database connector)

At this stage, you can run the tests via:

just catalog/test

# Alternatively, run all tests including longer-running ones
just catalog/test --extended

Edits to the source files or tests can be made on your local machine, then tests can be run in the container via the above command to see the effects.

If you’d like, it’s possible to login to the webserver container via:

just catalog/shell

If you just need to run an airflow command, you can use the airflow recipe. Arguments passed to airflow must be quoted:

just run scheduler airflow config list

To follow the logs of the running container:

just logs

To begin an interactive pgcli shell on the database container, run:

just catalog/pgcli

If you’d like to bring down the containers, run

just down

To reset the test DB (wiping out all databases, schemata, and tables), run

just down -v

docker volume prune can also be useful if you’ve already stopped the running containers, but be warned that it will remove all volumes associated with stopped containers, not just openverse-catalog ones.

To fully recreate everything from the ground up, you can use:

just recreate

Note: Any recipes or scripts which output files to the container’s mounted volumes will need to be run as the root user. This can be done with the DC_USER=root environment variable for just recipes. For example, see the generate-dag-docs recipe.

Directory Structure#

catalog/                                # Primary code directory
├── dags/                               # DAGs & DAG support code
│   ├── common/                         #   - Shared modules used across DAGs
│   ├── data_refresh/                   #   - DAGs & code related to the data refresh process
│   ├── database/                       #   - DAGs related to database actions (matview refresh, cleaning, etc.)
│   ├── maintenance/                    #   - DAGs related to airflow/infrastructure maintenance
│   ├── oauth2/                         #   - DAGs & code for Oauth2 key management
│   ├── providers/                      #   - DAGs & code for provider ingestion
│   │   ├── provider_api_scripts/       #       - API access code specific to providers
│   │   ├── provider_csv_load_scripts/  #       - Schema initialization SQL definitions for SQL-based providers
│   │   │   └── *.py                    #       - DAG definition files for providers
│   │   └── retired/                    #   - DAGs & code that is no longer needed but might be a useful guide for the future
│   ├── templates/                      # Templates for generating new provider code
└── *                                   # Documentation, configuration files, and project requirements

Publishing#

The docker image for the catalog (Airflow) is published to ghcr.io/WordPress/openverse-catalog.

Additional Resources#

  • 2022-01-12: cc-archive/cccatalog: The old repository for this catalog contains useful information for the original motivations and architecture of the Catalog.

For additional context see: