service-host

service-host

Installation

npm install service-host

CLI usage

# Start up a service host
node bin/start.js --config path/to/config.js

Config files should export an object.

Programmatic usage

var Host = require('service-host');

var host = new Host({
  debug: true,
  port: 9000,
});

host.addService({
  name: 'foo',
  handler: function(data, done) {
    // ...
    if (someError) {
      done(someError);
    } else {
      done(null, output);
    }
  }
});

// Call a service
host.callService(
  // The name of the service to call
  'foo',
  // An optional data set to pass to the service
  {},
  // An optional cache key to cache the output of the service
  'some-cache-key',
  // A callback which is provided with the resulting error and output
  function(err, output) {}
);

// Start a process which listens at the configured
// address and port
host.listen();

Communicating with the host

Headers

• X-Service: the name of the service that you want to call.
• X-Cache-Key: a token used to cache the output of the request, all concurrent or subsequent requests will resolve to the same output until it expires.

Sending data

Set the request's content-type to application/json and pass the data in as the request's body. It will be deserialised and passed to the service.

Configuring the host

// Default config

var host = new Host({
  // The address that the host will listen at
  address: '127.0.0.1',
  // The port that the host will listen at
  port: '63578',
  // If true, suppresses stdout/stderr from the host and service loggers
  silent: false,
  // If true, the host will write to stdout once it is listening for requests
  outputOnListen: true,
  // The maximum size of an incoming request's body
  requestDataLimit: '10mb',
  // The time between a cache key/value being set and its expiry
  serviceCacheTimeout: 24 * 60 * 60 * 1000, // 24 hours
  // An optional array of services to load during the host's initialization.
  // Services should be objects with `name` and either `file` or `handler`
  // properties. The `file` prop should be a path to a file which exports a
  // handler function.
  services: null
});