Please add HEALTHCHECK

[docwhat]

To ensure that the docker container starts up (and stays up) correctly I would like a HEALTHCHECK added.

It could be done by using a Node script to check /info to ensure it has status == 1.

[docwhat]

I think this should work using stock NodeJS stuff.

I based it on Anthony Mineo's blog post: Docker Healthcheck for your Node.js App.

const http = require("http");
const options = {
  host: "0.0.0.0",
  port: 8080,
  method: "GET",
  path: "/info",
  timeout: 2000
};

const healthCheck = http.request(options, res => {
  let body = "";

  res.setEncoding("utf8");
  res.on("data", chunk => (body += chunk));
  res.on("end", () => {
    if (res.statusCode === 200) {
      let payload = JSON.parse(body);
      if (payload.status === 1) {
        console.log(`HEALTHCHECK (v${payload.version}): online`);
        process.exit(0);
      } else if (payload.status === 2) {
        console.log(`HEALTHCHECK (v${payload.version}): offline`);
      } else if (payload.status === 3) {
        console.log(
          `HEALTHCHECK (v${payload.version}): not accepting new syncs`
        );
      } else {
        console.log(
          `HEALTHCHECK (v${payload.version}): unknown (status: ${payload.status})`
        );
      }
    } else {
      console.log(`HEALTHCHECK: ${res.statusCode}`);
    }
    process.exit(1);
  });
});

healthCheck.on("error", function(err) {
  console.error(`ERROR ${err}`);
  process.exit(1);
});

healthCheck.end();

[nero120]

Great idea @docwhat! Thanks for the PR, will give it a test and respond shortly.