SNS util methods for easier publishing with promises

sns-publish-helper.js

const AWS = require('aws-sdk');
const sns = new AWS.SNS();

function snsEventToJson(sns) {
  return JSON.parse(sns.Records[0].Sns.Message);
}

function jsonToSnsParams(jsonObject) {
  return {
    Message: JSON.stringify(jsonObject)
  };
}

function publish(params) {
  // sns topic from env
  params.TargetArn = process.env.SNS_TOPIC;
  return new Promise((resolve, reject) => {
    sns.publish(params, (err, data) => {
      if (err) {
        return reject(err);
      } else {
        return resolve(data);
      }
    });
  });
}

// usage:
function publishThisThing(param, paramtwo) {
  return publish(jsonToSnsParams({
    'keyOne':'blah', 
    'paramOne': param, 
    'paramTwo': paramtwo
  }));
}