Struct FileEnv 

pub struct FileEnv { /* private fields */ }

Provider that reads config values from the environment or from files pointed to by the environment.

The config value foo will be read either from the env variable FOO or from the file pointed to by FOO_FILE.

#[derive(Deserialize)]
struct Config {
  foo: String,
  bar: String,
}

// ENV:
// - `APP_FOO=foo_value`
// - `APP_BAR_FILE=./secret_file`
//
// Contents of the file `./secret_file`: `bar_value`
let config: Config = Figment::new()
    .merge(FileEnv::from_env(Env::prefixed("APP_")))
    .extract()?;
assert_eq!(config.foo, "foo_value");
assert_eq!(config.bar, "bar_value");

Implementations

impl FileEnv

pub fn from_env(env: Env) -> Self

Build from a figment::providers::Env. Any restriction or transformation applied to the env will propagate to the resulting FileEnv.

In particular, it is recommended to use figment::providers::Env::prefixed.

Note that figment::providers::Env::only and figment::providers::Env::ignore should not be used. Use FileEnv::only and FileEnv::ignore instead.

use figment::providers::Env;
use figment_file_env_provider::FileEnv;
let file_env = FileEnv::from_env(Env::prefixed("MY_APP_"));

pub fn with_suffix(self, suffix: &str) -> Self

Change the suffix used to detect env variables that point to files (“_FILE” by default).

// ENV: `APP_FOO_PATH=./secret_file`
// Contents of `./secret_file`: `32`
let config: Config = Figment::new()
    .merge(FileEnv::from_env(Env::prefixed("APP_")).with_suffix("_PATH"))
    .extract()?;
assert_eq!(config.foo, 32);

Note that the suffix cannot be changed after calling FileEnv::only or FileEnv::ignore.

pub fn only(self, keys: &[&str]) -> FileEnvWithRestrictions

Restrict the provider to process only the given list of keys (and their “_FILE” counterparts).

IMPORTANT: This should be used instead of figment::providers::Env::only otherwise the “_FILE” variants won’t be supported.

use figment::providers::Env;
use figment_file_env_provider::FileEnv;
// This provider will look at the variables FOO, FOO_FILE, BAR and BAR_FILE.
let file_env = FileEnv::from_env(Env::prefixed("MY_APP_")).only(&["foo", "bar"]);

pub fn ignore(self, keys: &[&str]) -> FileEnvWithRestrictions

Restrict the provider to ignore the given list of keys (and their “_FILE” counterparts).

IMPORTANT: This should be used instead of figment::providers::Env::ignore otherwise the “_FILE” variants won’t be ignored.

use figment::providers::Env;
use figment_file_env_provider::FileEnv;
// This provider will not look at the variables FOO, FOO_FILE, BAR and BAR_FILE.
let file_env = FileEnv::from_env(Env::prefixed("MY_APP_")).ignore(&["foo", "bar"]);

Trait Implementations

impl Clone for FileEnv

fn clone(&self) -> FileEnv

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Provider for FileEnv

fn metadata(&self) -> Metadata

Returns the Metadata for this provider, identifying itself and its configuration sources.

fn data(&self) -> Result<Map<Profile, Dict>, Error>

Returns the configuration data.

fn profile(&self) -> Option<Profile>

Optionally returns a profile to set on the Figment this provider is merged into. The profile is only set if self is merged.