@spalger/kibana/src/plugins/elasticsearch/lib/create_agent.js

Kibana is an open source (Apache Licensed), browser based analytics and search dashboard for Elasticsearch. Kibana is a snap to setup and start using. Kibana strives to be easy to get started with, while also being flexible and powerful, just like Elastic

var url = require('url');
var fs = require('fs');
var http = require('http');
var agentOptions;
module.exports = function (server) {
  var config = server.config();
  var target = url.parse(config.get('elasticsearch.url'));

  if (!agentOptions) {
    agentOptions = {
      rejectUnauthorized: config.get('elasticsearch.ssl.verify')
    };

    var customCA;
    if (/^https/.test(target.protocol) && config.get('elasticsearch.ssl.ca')) {
      customCA = fs.readFileSync(config.get('elasticsearch.ssl.ca'), 'utf8');
      agentOptions.ca = [customCA];
    }

    // Add client certificate and key if required by elasticsearch
    if (/^https/.test(target.protocol) &&
        config.get('elasticsearch.ssl.cert') &&
        config.get('elasticsearch.ssl.key')) {
      agentOptions.crt = fs.readFileSync(config.get('elasticsearch.ssl.cert'), 'utf8');
      agentOptions.key = fs.readFileSync(config.get('elasticsearch.ssl.key'), 'utf8');
    }
  }

  return new http.Agent(agentOptions);
};