reliable-get

Reliable HTTP get wrapper (cache and circuit breaker), best wrapped around things you dont trust very much.

Example options from Compoxure backend request:

var options = {
          url: targetUrl,
          cacheKey: targetCacheKey,
          cacheTTL: targetCacheTTL,
          timeout: utils.timeToMillis(backend.timeout || DEFAULT_LOW_TIMEOUT),
          headers: backendHeaders,
          tracer: req.tracer,
          statsdKey: 'backend_' + utils.urlToCacheKey(host),
          eventHandler: eventHandler
        };

From compoxure fragment request:

var options = {
      url: url,
      timeout: timeout,
      cacheKey: cacheKey,
      cacheTTL: cacheTTL,
      explicitNoCache: explicitNoCache,
      headers: optionsHeaders,
      tracer: req.tracer,
      statsdKey: statsdKey,
      eventHandler: eventHandler
  }

Property	Description	Example / Default	Required
url	Service to get	http://my-service.tes.co.uk	Yes
timeout	Timeout for service	5000	No
cacheKey	Key to store cached value against	my-service_tes_co_uk	No
cacheTTL	TTL of cached value	1 minute	No
explicitNoCache	Do not cache under any circumstances	false	No
headers	Headers to send with request		No
tracer	Unique value to pass with request		No
type	Type of request, used for statsd and logging		No
statsdKey	Key that statsd events will be posted to		No
eventHandler	Object (see below) for logging and stats		No

Event Handler

To allow Reliable Get to report back on status, at the moment we require you to pass in a simple object:

var eventHandler = {
  logger: function(level, message, data) {},
  stats: function(type, key, value) {}
}

This will likely get replaced with a more standard EventEmitter at some point when we get around to it (this is a legacy of the extraction of this code from another project for now).