registry/notifications/endpoint.go
Noah Treuhaft ad6bb66faf Add notification filtering by target media type
The Hub registry generates a large volume of notifications, many of
which are uninteresting based on target media type.  Discarding them
within the notification endpoint consumes considerable resources that
could be saved by discarding them within the registry.  To that end,
this change adds registry configuration options to restrict the
notifications sent to an endpoint based on target media type.

Signed-off-by: Noah Treuhaft <noah.treuhaft@docker.com>
2016-09-16 12:01:03 -07:00

93 lines
2.3 KiB
Go

package notifications
import (
"net/http"
"time"
)
// EndpointConfig covers the optional configuration parameters for an active
// endpoint.
type EndpointConfig struct {
Headers http.Header
Timeout time.Duration
Threshold int
Backoff time.Duration
IgnoredMediaTypes []string
Transport *http.Transport
}
// defaults set any zero-valued fields to a reasonable default.
func (ec *EndpointConfig) defaults() {
if ec.Timeout <= 0 {
ec.Timeout = time.Second
}
if ec.Threshold <= 0 {
ec.Threshold = 10
}
if ec.Backoff <= 0 {
ec.Backoff = time.Second
}
if ec.Transport == nil {
ec.Transport = http.DefaultTransport.(*http.Transport)
}
}
// Endpoint is a reliable, queued, thread-safe sink that notify external http
// services when events are written. Writes are non-blocking and always
// succeed for callers but events may be queued internally.
type Endpoint struct {
Sink
url string
name string
EndpointConfig
metrics *safeMetrics
}
// NewEndpoint returns a running endpoint, ready to receive events.
func NewEndpoint(name, url string, config EndpointConfig) *Endpoint {
var endpoint Endpoint
endpoint.name = name
endpoint.url = url
endpoint.EndpointConfig = config
endpoint.defaults()
endpoint.metrics = newSafeMetrics()
// Configures the inmemory queue, retry, http pipeline.
endpoint.Sink = newHTTPSink(
endpoint.url, endpoint.Timeout, endpoint.Headers,
endpoint.Transport, endpoint.metrics.httpStatusListener())
endpoint.Sink = newRetryingSink(endpoint.Sink, endpoint.Threshold, endpoint.Backoff)
endpoint.Sink = newEventQueue(endpoint.Sink, endpoint.metrics.eventQueueListener())
endpoint.Sink = newIgnoredMediaTypesSink(endpoint.Sink, config.IgnoredMediaTypes)
register(&endpoint)
return &endpoint
}
// Name returns the name of the endpoint, generally used for debugging.
func (e *Endpoint) Name() string {
return e.name
}
// URL returns the url of the endpoint.
func (e *Endpoint) URL() string {
return e.url
}
// ReadMetrics populates em with metrics from the endpoint.
func (e *Endpoint) ReadMetrics(em *EndpointMetrics) {
e.metrics.Lock()
defer e.metrics.Unlock()
*em = e.metrics.EndpointMetrics
// Map still need to copied in a threadsafe manner.
em.Statuses = make(map[string]int)
for k, v := range e.metrics.Statuses {
em.Statuses[k] = v
}
}