Crate entrypoint

an (opinionated) app wrapper to eliminate main function boilerplate

Eliminate boilerplate by smartly integrating:

• anyhow: for easy error handling
• clap: for easy CLI parsing
• dotenv: for easy environment variable management
• tracing: for easy logging

In lieu of main(), an entrypoint function is defined.

Perfectly reasonable setup/config is done automagically. More explicitly, the entrypoint function can be written as if:

• anyhow::Error is ready to propogate
• CLI have been parsed
• .dotenv files have already been processed and populated into the environment
• logging is ready to use

Customization can be achieved by overriding various trait default implementations (or preferably/more-typically by using the provided attribute macros).

Examples

use entrypoint::prelude::*;

#[derive(clap::Parser, DotEnvDefault, LoggerDefault, Debug)]
#[log_format(pretty)]
#[log_level(entrypoint::LevelFilter::DEBUG)]
#[log_writer(std::io::stdout)]
struct Args {}

// this function replaces `main`
#[entrypoint::entrypoint]
fn main(args: Args) -> anyhow::Result<()> {
    // tracing & parsed clap struct are ready-to-use
    debug!("entrypoint input args: {:#?}", args);

    // env vars already have values from dotenv file(s)
    for (key, value) in std::env::vars() {
        println!("{key}: {value}");
    }

    // easy error propagation w/ anyhow
    Ok(())
}

Feature Flags

Name	Description	Default?
macros	Enables optional utility macros	Yes

Re-exports

pub extern crate anyhow;

pub extern crate clap;

pub extern crate entrypoint_macros;

pub extern crate tracing;

pub extern crate tracing_subscriber;

pub use crate::prelude::*;

Modules

macros

re-export entrypoint_macros

prelude

essential traits and re-exports

Traits

DotEnvParser

blanket implementation for automatic dotenv processing

DotEnvParserConfig

automatic dotenv processing configuration

Entrypoint

blanket implementation to wrap a function with “main()” setup/initialization boilerplate

Logger

blanket implementation for automatic tracing & tracing_subscriber initialization

LoggerConfig

automatic tracing & tracing_subscriber configuration