envmnt
Environment variables utility functions.
Overview
This library has many helper functions to access/modify/check environment variables.
Usage
Simply include the library and invoke the various utility functions.
Get/Set/Remove environment variables
use envmnt::{ExpandOptions, ExpansionType};
fn main() {
if !envmnt::exists("MY_ENV_VAR") {
envmnt::set("MY_ENV_VAR", "SOME VALUE");
}
let mut value = envmnt::get_or("MY_ENV_VAR", "DEFAULT_VALUE");
println!("Env Value: {}", &value);
value = envmnt::get_or_panic("MY_ENV_VAR");
println!("Env Value: {}", &value);
let pre_value = envmnt::get_set("MY_ENV_VAR", "SOME NEW VALUE");
let value = envmnt::get_or("MY_ENV_VAR", "DEFAULT_VALUE");
println!("New Env Value: {}", &value);
println!("Previous Env Value: {:?}", &pre_value);
let var_was_set = envmnt::set_optional("MY_ENV_VAR", &Some("OPTIONAL VALUE"));
println!("Env Was Modified: {}", var_was_set);
let all_vars = envmnt::vars(); // returned as Vec<(String, String)>
for (key, value) in all_vars {
println!("{}: {}", key, value);
}
envmnt::set("MY_ENV_VAR2", "SOME VALUE2");
let value = envmnt::get_any(&vec!["MY_ENV_VAR1", "MY_ENV_VAR2"], "default");
println!("MY_ENV_VAR1 exists: {}", envmnt::exists("MY_ENV_VAR1"));
println!("MY_ENV_VAR2 exists: {}", envmnt::exists("MY_ENV_VAR2"));
println!("Found value: {}", value);
let mut options = ExpandOptions::new();
options.expansion_type = Some(ExpansionType::Unix);
let mut value = envmnt::expand("Env: MY_ENV value is: ${MY_ENV}", Some(options));
println!("Expanded: {}", &value);
options.expansion_type = Some(ExpansionType::UnixBracketsWithDefaults);
value = envmnt::expand(
"Env: MY_ENV_NOT_FOUND value is: ${MY_ENV_NOT_FOUND:default value}",
Some(options),
);
println!("Expanded: {}", &value);
}
Get/Set boolean environment variables and other comparisons
fn main() {
envmnt::set_bool("FLAG_VAR", true);
let mut flag_value = envmnt::is_or("FLAG_VAR", false);
println!("Bool Flag: {}", &flag_value);
flag_value = envmnt::is("FLAG_VAR");
assert!(flag_value);
envmnt::set_bool("FLAG_VAR", true);
assert!(envmnt::is_equal("FLAG_VAR", "true"));
envmnt::set("MY_ENV_VAR", "SOME VALUE");
let same = envmnt::is_equal("MY_ENV_VAR", "SOME VALUE");
println!("Value Is Same: {}", &same);
let mut contains = envmnt::contains("MY_ENV_VAR", "_ENV_");
println!("Value Contained: {}", &contains);
contains = envmnt::contains_ignore_case("MY_ENV_VAR", "_env_");
println!("Value Contained (case insensitive): {}", &contains);
}
Get/Set numeric environment variables
fn main() {
// all numeric data types: u8/i8/u16/i16/u32/i32/u64/i64/u128/i128/f32/f64/isize/usize
// are supported by specific set/get functions.
envmnt::set_u8("U8_TEST_ENV", 50);
let mut value_u8 = envmnt::get_u8("U8_TEST_ENV", 5);
println!("u8 value: {}", value_u8);
envmnt::set_isize("ISIZE_TEST_ENV", -50);
let mut value_isize = envmnt::get_isize("ISIZE_TEST_ENV", 5);
println!("isize value: {}", value_isize);
// increment/decrement values
value_isize = envmnt::increment("U8_TEST_ENV");
assert_eq!(value_isize, 51);
value_u8 = envmnt::get_u8("U8_TEST_ENV", 5);
assert_eq!(value_u8, 51);
value_isize = envmnt::decrement("U8_TEST_ENV");
assert_eq!(value_isize, 50);
value_u8 = envmnt::get_u8("U8_TEST_ENV", 5);
assert_eq!(value_u8, 50);
}
Get/Set list environment variables
fn main() {
envmnt::set_list(
"LIST_TEST_ENV",
&vec!["1".to_string(), "2".to_string(), "3".to_string()],
);
let mut values = envmnt::get_list("LIST_TEST_ENV").unwrap();
println!("List Values: {:?}", values);
let mut same = envmnt::is_equal("LIST_TEST_ENV", "1;2;3");
println!("Same: {}", same);
let mut options = envmnt::ListOptions::new();
options.separator = Some(",".to_string());
envmnt::set_list_with_options(
"LIST_TEST_ENV",
&vec!["1".to_string(), "2".to_string(), "3".to_string()],
&options,
);
values = envmnt::get_list_with_options("LIST_TEST_ENV", &options).unwrap();
println!("List Values: {:?}", values);
same = envmnt::is_equal("LIST_TEST_ENV", "1,2,3");
println!("Same: {}", same);
}
Bulk Operations
use indexmap::IndexMap;
fn main() {
let mut env: IndexMap<String, String> = IndexMap::new();
env.insert("ENV_VAR1".to_string(), "MY VALUE".to_string());
env.insert("ENV_VAR2".to_string(), "MY VALUE2".to_string());
envmnt::set_all(&env);
let value = envmnt::get_or_panic("ENV_VAR1");
println!("Value Is: {}", &value);
let mut found = envmnt::is_any_exists(&vec!["ENV_VAR1", "ENV_VAR2"]);
println!("Any Found: {}", &found);
found = envmnt::is_all_exists(&vec!["ENV_VAR1", "ENV_VAR2"]);
println!("All Found: {}", &found);
envmnt::remove_all(&vec!["ENV_VAR1", "ENV_VAR2"]);
found = envmnt::is_any_exists(&vec!["ENV_VAR1", "ENV_VAR2"]);
println!("Any Found: {}", &found);
env = IndexMap::new();
env.insert("ENV_VAR1".to_string(), "MY VALUE".to_string());
env.insert("ENV_VAR2".to_string(), "MY VALUE2".to_string());
let eval_env = |value: String| {
let mut buffer = String::from("VALUE-");
buffer.push_str(&value);
buffer
};
envmnt::evaluate_and_set_all(&env, eval_env);
let value = envmnt::get_or_panic("ENV_VAR1");
println!("Value Is: {}", &value);
}
File Operations
fn main() {
let mut output = envmnt::load_file("./src/test/var.env");
assert!(output.is_ok());
let eval_env = |value: String| {
let mut buffer = String::from("PREFIX-");
buffer.push_str(&value);
buffer
};
output = envmnt::evaluate_and_load_file("./src/test/var.env", eval_env);
assert!(output.is_ok());
}
Installation
In order to use this library, just add it as a dependency:
[dependencies]
envmnt = "^0.8.4"
API Documentation
See full docs at: API Docs
Contributing
Release History
See Changelog
License
Developed by Sagie Gur-Ari and licensed under the Apache 2 open source license.