Function sensible_env_logger::try_init_custom_env_and_builder

pub fn try_init_custom_env_and_builder(
    log_env_var: &str, 
    global_log_env_var: &str, 
    package_name: &str, 
    module_name: &str, 
    builder_fn: impl Fn() -> Builder
) -> Result<(), SetLoggerError>

Initializes the global logger with a pretty, sensible env logger, with custom variable names and a custom builder function.

This should be called early in the execution of a Rust program, and the global logger may only be initialized once. Future initialization attempts will return an error.

Example

sensible_env_logger::try_init_custom_env_and_builder(
    "MY_RUST_LOG",
    "MY_GLOBAL_RUST_LOG",
    env!("CARGO_PKG_NAME"),
    module_path!(),
    sensible_env_logger::pretty::formatted_timed_builder,
);

How It works

The package_name and module_name arguments are ideally evaluated from the $CARGO_PKG_NAME and $CARGO_CRATE_NAME environment variables respectively. These environment variables are automatically set by Cargo when compiling your crate. It then builds a custom directives string in the same form as the $RUST_LOG environment variable, and then parses this generated directives string using env_logger::Builder::parse_filters.

Errors

This function fails to set the global logger if one has already been set.