Postgres

how to configure preen to connect to Postgres databases.

Preen uses the pgx library to connect to Postgres databases.

Example Preen Source Configuration

# FILENAME: ~/.preen/sources.yaml
sources:
  - name: postgres-example
    engine: postgres
    connection:
      host: localhost
      port: 5432
      database: postgres
      username: ${PG_USER} # You can specify environment variables in the sources.yaml file.
      password: ${PG_PASSWORD}    

Postgres Models

Postgres models are defined as a YAML file that contains a SQL query.

# FILENAME: ~/.preen/models/users.yaml
name: users # This name needs to be unique
type: sql
query: |
  select
    users.id,
    users.first_name,
    users.last_name,
    users.birthday
  from
    users;

Postgres Type Mappings

A comprehensive list of Postgres type mappings can be found here. We use the pgtype library to map Postgres types to Go types, with a few custom mappings for things like float64, duration, and time types.

Code References

• types.go

• postgres.go