docker-stat-example-rust

main.rs

extern crate regex;
extern crate serde;
extern crate serde_json;
extern crate tiny_http;

#[macro_use]
extern crate serde_derive;

use serde_json::Error;
use std::process::Command;
use regex::Regex;
use std::collections::HashMap;

#[derive(Serialize, Deserialize)]

struct DockerStat {
    container: String,
    cpu: String,
    memory: HashMap<String, String>,
}

fn main() {
    use tiny_http::{Server, Response};

    let server = Server::http("0.0.0.0:8000").unwrap();

    for request in server.incoming_requests() {

        let response = Response::from_string("hello world");
        request.respond(response);
    }
}

fn docker_stats() {
    let output = get_docker_stats();
    parse_docker_state(output);
}


// get docker stats as json formatted string
fn get_docker_stats() -> String {
    let output =
        Command::new("sh")
            .arg("scripts/docker-stats.sh")
            .output()
            .expect("Failed to get docker stats");

    let stdout = output.stdout;

    let s = match String::from_utf8(stdout) {
        Ok(v) => v,
        Err(e) => panic!("Invalid UTF-8 sequence: {}", e),
    };

    return s;
}

// Parse json docker stats into Structure List
fn parse_docker_state (docker_state_as_str: String) -> String {
    let list = Vec(DockerStat);

    for line in docker_state_as_str.split('\n') {
        let json = replace_multiple_whitespace(line);
        let res = output_to_struct(json);

        let stat = res.ok();
        match stat {
            None => println!("ok"),
            Some(docker_stat) => {
                println!("{}", docker_stat.container)
            }
        }
    }

    return String::from("");
}

// docker stats json line to DockerStat structure
fn output_to_struct(line:String) -> Result<DockerStat, Error> {
    let docker_stat: DockerStat = serde_json::from_str(&line)?;

    Ok(docker_stat)
}

// remove multiple whitespace in string
fn replace_multiple_whitespace (before : &str) -> String {
    let re = Regex::new(r" +").unwrap();

    let after = re.replace_all(before, " ");
    return after.to_string();
}