YAML Nested Values Are Not Usable Via Environment Variables with `Env::split` about figment HOT 2 CLOSED

Figment is working correctly, but what you've written does not match the configuration you're passing in. There are several items of concern.

#[serde(rename = "instance-host")]
pub instance_host: String,

By doing this, you're changing the field name to instance-host. As a result, a field passed in as instance_host will not be recognized. Maybe you meant to use serde(alias)?

Similar to the above, using figment_file_provider_adapter...

FileAdapter is not part of figment. Please consult that repository for issues relevant to that type.

As can be seen from code below, I have Env::split set correctly

I assume based on your intro text that you expect MASTODON_INSTANCE_HOST=foo to work with the following:

Figment::new().merge(Env::raw().split('_'))

For MASTODON_INSTANCE_HOST-foo, this would produce the equivalent of {mastodon={instance={host=foo}}}, as indicated in the docs. This does not match the structure you defined. Perhaps you want: Env::prefixed("MASTADON_"), to use serde(alias) instead of serde(rename), and then to extract to MastodonConfig directly. Or perhaps you need to split on __ instead; then MASTODON__INSTANCE_HOST would work, assuming you fix your structure.

from figment.

That all makes sense, sorry for creating a rushed-in issue without checking the library much. Thanks a lot!

from figment.