Crate de_env

🦀 de_env

Deserialize environment variables through serde.

---

You may be looking for:

• API Documentation
• Crates.io

Example

Assuming we have a LOG and PORT environment variable:

#[derive(serde::Deserialize, Debug)]
#[serde(rename_all = "SCREAMING_SNAKE_CASE")]
struct Config {
    log: String,
    port: u16
}

let config: Config = de_env::from_env().unwrap();

println!("{config:#?}");

Boolean parsing

Boolean parsing is case-insensitive.

If the truthy-falsy feature is enabled (default):

• Truthy values:
  • true or its shorthand t
  • yes or its shorthand y
  • on
  • 1
• Falsy values:
  • false or its shorthand f
  • no or its shorthand n
  • off
  • 0

If the truthy-falsy feature is disabled, only true and false are considered valid booleans.

Enum

Only unit variants can be deserialized.

Assuming we have a LEVEL environment variable set to HIGH, MEDIUM or LOW:

#[derive(serde::Deserialize, Debug)]
#[serde(rename_all = "SCREAMING_SNAKE_CASE")]
enum Level {
    High,
    Medium,
    Low
}

#[derive(serde::Deserialize, Debug)]
#[serde(rename_all = "SCREAMING_SNAKE_CASE")]
struct Pool {
    level: Level,
}

let pool: Pool = de_env::from_env().unwrap();

println!("{pool:#?}");

Unsupported types

• Nested structs
• Nested enums
• Nested Maps
• Non-unit enum variants
• Tuples
• Sequences
• Byte Arrays

Structs

Error

Represent an error that may arise when deserializing.

Functions

from_env

Deserialize an instance of T from the environment variables of the current process.

from_env_prefixed

Deserialize an instance of T from the environment variables of the current process with the specified prefix.

from_iter

Deserialize an instance of T from an iterator of name-value String pairs.

from_iter_os

Deserialize an instance of T from an iterator of name-value OsString pairs.

Type Definitions

Result

Convenience alias for a Result with this crate Error type.