await.js

let redis = require('redis');
let retry = require('retry')

function ping(callback) {
  let operation = retry.operation({
    retries: process.env.ATTEMPTS ? parseInt(process.env.ATTEMPTS) : 60,
    factor: 1,
    randomize: false
  });

  operation.attempt(function(currentAttempt) {
    try {
      var client = redis.createClient({
        url: process.env.REDIS_URL
      });

      client.ping(function(err, result) {
        if(operation.retry(err)) {
          return;
        }

        callback(err ? operation.mainError() : null, result);
      });
    } catch(err) {
      if(operation.retry(err)) {
        return;
      }

      callback(err || operation.mainError());
    }
  });
};

ping(function(err, result) {
  if(err) {
    console.log(err);
    console.log('Connection failed');
    process.exit(1);
  } else {
    console.log('Connection ok');
    process.exit(0);
  }
});

a guess at how it might work after skimming https://github.com/tim-kos/node-retry

function ping (callback) {
  const operation = retry.operation({
    retries: process.env.ATTEMPTS ? parseInt(process.env.ATTEMPTS) : 60,
    factor: 1,
    randomize: false
  })

  const client = redis.createClient({
    url: process.env.REDIS_URL
  })

  operation.attempt(function (attemptCount) {
    client.ping(function (err, result) {
      if (operation.retry(err)) {
        if (err) {
          // if err is truthy, then then operation.retry(err) triggered a retry
          console.log('retrying due to ping error:', err, err.stack)
          return
        }
        // if falsey, then we simply hit retry limit and operation.retry(err) did not trigger a retry (we are done)
        callback(new Error('MAXIMUM_RETRIES'))
        return
      }

      // if we made it this far, then ping() was successful (we are done)
      callback(null, result)
    })
  })
}

i don't really understand the intended api usage of the retry module tho.