Logs

• troubleshooting
• performance
• usage
• audit
• stats from it
• ...

Logs

• take place
• usefull
• try to be valuable

Logs

new connection

X just connect

[2018-04-17 18:22:25]new connection: X with a login and password on mobile

[2018-04-17 18:22:25]new connection: "X" with "credentials" on "mobile" ("Android 8.0.0 / ONEPLUS A500...")

[2018-04-17 18:22:25]new connection: {user} with {type} on {source} ({model}) - {"type": "credentials", "user": "H3fAh9bppeg=xuHy8woEtOfYYI18tLM76A==BKUvKCztSNl8", "source": "mobile", "model": "Android 8.0.0 / ONEPLUS A500..."}

[2018-04-17 18:22:25] [INFO]new connection: {user} with {type} on {source} ({model}) - {"type": "credentials", "user": "H3fAh9bppeg=xuHy8woEtOfYYI18tLM76A==BKUvKCztSNl8", "source": "mobile", "model": "Android 8.0.0 / ONEPLUS A500..."}

Logs

• Standard
  • RFC 5424 => syslog
  • RFC 5426 => syslog over udp
  • ...
• + habits
• a lot of tools to deal with them
  • don't reinvent the wheel
    • syslog, rsyslog, logrotate, ELK, ...
  • speak to your sysadmin!

In rust

rust native - error

• Error
• !panic()
• Option|Result .expect()
• panic = 'abort' in Cargo.toml
• RUST_BACKTRACE=1

rust native - error

fn main() {
    use std::error::Error;

    match "xc".parse::<u32>() {
        Err(e) => {
            println!("1. Error parsing some value: {}", e.description());
            eprintln!("2. Error parsing some value: {}", e.description());
        }
        _ => println!("No error"),
    }
}

Demo

rust native - log

• output to screen
• file
  • open a file
  • format a string
  • write it
  • close the file

Crates?

Let's choose one

Error - crates

• simple-error
• derive-error
• yade
• failure
• error-chain
• ...

Logs - crates

• log
  • env_logger
    • pretty_env_logger
  • simplelog
  • stderrlog
  • flexi_logger
  • log4rs
• ​slog

Demo