Module lib/rstreams-config-provider-chain

Creates a configuration provider chain that searches for RStreams configurations in a list of configuration providers specified by the {providers} property.

By default, the chain will use the {defaultProviders} to resolve configurations. These providers will look in the environment using the {RStreams.EnvironmentConfiguration} class with the 'LEO' and 'RSTREAMS' prefixes.

Setting Providers

Each provider in the {providers} list should be a function that returns a {RStreams.Configuration} object, or a hardcoded Configuration object. The function form allows for delayed execution of the credential construction.

Resolving Configurations from a Chain

Call {resolve} to return the first valid credential object that can be loaded by the provider chain.

For example, to resolve a chain with a custom provider that checks a file on disk after the set of {defaultProviders}:

let envProvider = new RStreams.EnvironmentConfiguration('MyEnvVar');
let chain = new RStreams.ConfigProviderChain([envProvider], ProvidersInputType.Append);
chain.resolveSync();

The above code will return the envProvider object if the env contains configuration and the defaultProviders do not contain any configuration settings.