Service Discovery

A ServiceDiscovery is a function that receives the desired service name and must return a string value (or a Promise<string>) to inform the target destination for this proxy.

The serviceDiscovery middleware is initialized receiving a config parameter that will receive any options declared in your middleware configuration plus two configurations:

Property	Type	Description	Required
clientAgent	any	The client created by the serviceDiscovery provider middleware.	true
ssl	boolean	True if the requests to the target service must use SSL (https).	false

Each serviceDiscovery middleware must be defined on its own .js file.

Example:

/**
 * Where config contains a reference by the clientAgent created by the serviceDiscovery provider and a ssl flag
 */
module.exports = function (config) {  
  return (serviceName) => {
    return (config.ssl?'https://':'http://') + 
             config.clientAgent.get(serviceName).address + ':' +
             config.clientAgent.get(serviceName).port;
  };
};

or, using Promises:

module.exports = function (config) {
  return (serviceName) => {
    return new Promise((resolve, reject) => {
      config.clientAgent.get(serviceName)
        .then(service => {
          resolve((config.ssl?'https://':'http://') + service.address + ': ' + service.port)
        }).catch(reject);
    };
  }
};