Crate itconfig[−][src]
itconfig
Simple configuration with macro for rust application.
Motivation
I began to use rust with web programming experience where environment variables are widely used and often there are more then 50 of them. First I looked at already created libraries. But there it’s necessary to initialise structure that needs to be moved to each function where you need variable. It uses little bit memory, but configuration lifetime is as long as application lifetime. Because of it I decided to create my own library.
Installation
These macros require a Rust compiler version 1.31 or newer.
Add itconfig = { version = "1.0", features = ["macro"] }
as a dependency in Cargo.toml
.
Cargo.toml
example:
[package]
name = "my-crate"
version = "0.1.0"
authors = ["Me <user@rust-lang.org>"]
[dependencies]
itconfig = { version = "1.0", features = ["macro"] }
Basic usage
use itconfig::config; use std::env; //use dotenv::dotenv; config! { DEBUG: bool => false, #[env_name = "APP_HOST"] HOST: String => "127.0.0.1", database { URL < ( "postgres://", POSTGRES_USERNAME => "user", ":", POSTGRES_PASSWORD => "pass", "@", POSTGRES_HOST => "localhost:5432", "/", POSTGRES_DB => "test", ), pool { MAX_SIZE: usize => 15, }, }, sentry { DSN: Option<&'static str>, }, feature { static CORS: bool => false, static GRAPHQL_PLAYGROUND: bool => false, }, } fn main () { // dotenv().expect("dotenv setup to be successful"); // or env::set_var("FEATURE_CORS", "true"); config::init(); assert_eq!(config::HOST(), String::from("127.0.0.1")); assert_eq!(config::database::URL(), String::from("postgres://user:pass@localhost:5432/test")); assert_eq!(config::database::pool::MAX_SIZE(), 15); assert_eq!(config::sentry::DSN(), None); assert_eq!(config::feature::CORS(), true); }
Macro is an optional feature, disabled by default. You can use this library without macro.
use itconfig::*; use std::env; // use dotenv::dotenv; fn main() { // dotenv().expect("dotenv setup to be successful"); // or env::set_var("DATABASE_URL", "postgres://127.0.0.1:5432/test"); let database_url = get_env::<String>("DATABASE_URL").unwrap(); let new_profile: bool = get_env_or_default("FEATURE_NEW_PROFILE", false); let articles_per_page: u32 = get_env_or_set_default("ARTICLES_PER_PAGE", 10); }
Available features
- default - [“primitives”]
- macro - Activates
config!
macros for easy configure web application. - primitives - Group for features:
numbers
andbool
. - numbers - Group for features:
int
,uint
andfloat
. - int - Group for features:
i8
,i16
,i32
,i64
,i128
andisize
. - uint - Group for features:
u8
,u16
,u32
,u64
,u128
andusize
. - float - Group for features:
f32
andf64
- i8 - impl EnvString for
i8
type - i16 - impl EnvString for
i16
type - i32 - impl EnvString for
i32
type - i64 - impl EnvString for
i64
type - i128 - impl EnvString for
i128
type - isize - impl EnvString for
isize
type - u8 - impl EnvString for
u8
type - u16 - impl EnvString for
u16
type - u32 - impl EnvString for
u32
type - u64 - impl EnvString for
u64
type - u128 - impl EnvString for
u128
type - usize - impl EnvString for
usize
type - f32 - impl EnvString for
f32
type - f64 - impl EnvString for
f64
type - bool - impl EnvString for
bool
type - json_array - Add EnvString impl for vector type (uses optional
serde_json
package). ⚠ DEPRECATED
Macros
config | This API requires the following crate features to be activated: |
Structs
EnvString | Wrapper under String type. |
Enums
ArrayEnvError | Deprecated Error type for json array implementation |
EnvError | The error type for operations interacting with environment variables |
Traits
FromEnvString | Simple and safe type conversions that may fail in a controlled way under some circumstances. |
ToEnvString | A trait for converting value to EnvString. |
Functions
get_env | Try to read environment variable and parse to expected type. You may to put to argument
any type with |
get_env_or | This function returns env variable as |
get_env_or_default | This function is similar as |
get_env_or_panic | This function is similar as |
get_env_or_set_default | This function is similar as |
get_vec_env | Try to read environment variable, split by separator and parse each item to expected type. |
get_vec_env_or | This function returns env variable as |
get_vec_env_or_default | This function is similar as |
get_vec_env_or_panic | This function is similar as |
get_vec_env_or_set_default | This function is similar as |
maybe_get_env | Same as get_env but returns Option enum instead Result |
maybe_get_vec_env | Same as get_vec_env but returns Option enum instead Result |