Janeiro - Configuration Management

• Define configuration options
• Select configuration source
• Python dictionnary
• Environment variables

Define configuration options

In your application, you should declare options coming from configuration.

DATABASE_MAX_CONNECTIONS_OPTION = ConfigOption(
    key="database.max_connections",
    type=int
)

Then whenever needed, you can load values for these options from config using:

max_connections = config.get(DATABASE_MAX_CONNECTIONS_OPTION)

Read following sections to understand how to make your own Config object

Select configuration source

Python dictionnary

DictConfigSource is the most simple configuration source. It loads config options from the python dictionnary it takes as a parameter.

from janeiro.config import Config, DictConfigSource

config = Config(
    source=DictConfigSource({
        "database.url": "sqlite:///mydb.sqlite",
        "database.max_connections": "5"
    })
)

Environment variables

EnvConfigSource loads config options from environment variables. It takes an optional prefix that can be used to prepend app name to all variables.

from janeiro.config import Config, EnvConfigSource

config = Config(source=EnvConfigSource(prefix="app"))

With this configuration, accessing config option with key database.max_connections would read value from environment variable APP_DATABASE_MAX_CONNECTIONS.