Mage `io_config.yaml`¶

Truthound can read Mage's io_config.yaml or io_config.yml so that data source details live with the Mage project instead of being duplicated in every quality block.

Discovery Behavior¶

The loader searches the current directory and parent directories for:

io_config.yaml
io_config.yml

The lookup is read-only. If no config file is found, Truthound still falls back to its safe runtime defaults.

Example Shape¶

default:
  TRUTHOUND_ENGINE: truthound
  TRUTHOUND_TIMEOUT: 300

data_sources:
  warehouse:
    type: postgres
    host: localhost
    port: 5432
    database: analytics
    username: ${PGUSER}
    password: ${PGPASSWORD}

  bronze_users:
    type: file
    path: data/bronze/users.parquet
    format: parquet

Supported Source Families¶

The config layer supports common source families such as:

file-backed inputs
PostgreSQL and MySQL
Snowflake, BigQuery, and Redshift
S3, GCS, and Azure-style object stores
custom source definitions with extra options

Environment Variable Resolution¶

Environment placeholders such as ${PGPASSWORD} are resolved when config values are read. This keeps secrets out of checked-in project files.

How To Use It¶

from truthound_mage import load_io_config

io_config = load_io_config()
source = io_config.get_source("warehouse")

In practice, many teams will not call load_io_config() directly in every block. They centralize it once in a helper file and pass the resulting source configuration into block factories.

Operational Guidance¶

keep source names stable across environments
prefer environment-backed credentials over literal secrets
treat io_config.yaml as project infrastructure, not ad hoc local state

Mage io_config.yaml¶