Struct Handler

modules/caddyhttp/reverseproxy/reverseproxy.go:100–251

Handler implements a highly configurable and production-ready reverse proxy. Upon proxying, this module sets the following placeholders (which can be used both within and after this handler; for example, in response headers): Placeholder | Description ------------|------------- `{http.reverse_prox

// `{http.reverse_proxy.duration_ms}` | Same as 'duration', but in milliseconds.
// `{http.reverse_proxy.retries}` | The number of retries actually performed to communicate with an upstream.
type Handler struct {
	// Configures the method of transport for the proxy. A transport
	// is what performs the actual "round trip" to the backend.
	// The default transport is plaintext HTTP.
	TransportRaw json.RawMessage `json:"transport,omitempty" caddy:"namespace=http.reverse_proxy.transport inline_key=protocol"`

	// A circuit breaker may be used to relieve pressure on a backend
	// that is beginning to exhibit symptoms of stress or latency.
	// By default, there is no circuit breaker.
	CBRaw json.RawMessage `json:"circuit_breaker,omitempty" caddy:"namespace=http.reverse_proxy.circuit_breakers inline_key=type"`

	// Load balancing distributes load/requests between backends.
	LoadBalancing *LoadBalancing `json:"load_balancing,omitempty"`

	// Health checks update the status of backends, whether they are
	// up or down. Down backends will not be proxied to.
	HealthChecks *HealthChecks `json:"health_checks,omitempty"`

	// Upstreams is the static list of backends to proxy to.
	Upstreams UpstreamPool `json:"upstreams,omitempty"`

	// A module for retrieving the list of upstreams dynamically. Dynamic
	// upstreams are retrieved at every iteration of the proxy loop for
	// each request (i.e. before every proxy attempt within every request).
	// Active health checks do not work on dynamic upstreams, and passive
	// health checks are only effective on dynamic upstreams if the proxy
	// server is busy enough that concurrent requests to the same backends
	// are continuous. Instead of health checks for dynamic upstreams, it
	// is recommended that the dynamic upstream module only return available
	// backends in the first place.
	DynamicUpstreamsRaw json.RawMessage `json:"dynamic_upstreams,omitempty" caddy:"namespace=http.reverse_proxy.upstreams inline_key=source"`

	// Adjusts how often to flush the response buffer. By default,
	// no periodic flushing is done. A negative value disables
	// response buffering, and flushes immediately after each
	// write to the client. This option is ignored when the upstream's
	// response is recognized as a streaming response, or if its
	// content length is -1; for such responses, writes are flushed
	// to the client immediately.
	FlushInterval caddy.Duration `json:"flush_interval,omitempty"`

	// A list of IP ranges (supports CIDR notation) from which
	// X-Forwarded-* header values should be trusted. By default,
	// no proxies are trusted, so existing values will be ignored
	// when setting these headers. If the proxy is trusted, then
	// existing values will be used when constructing the final
	// header values.
	TrustedProxies []string `json:"trusted_proxies,omitempty"`

	// Headers manipulates headers between Caddy and the backend.
	// By default, all headers are passed-thru without changes,
	// with the exceptions of special hop-by-hop headers.
	//
	// X-Forwarded-For, X-Forwarded-Proto and X-Forwarded-Host
	// are also set implicitly.
	Headers *headers.Handler `json:"headers,omitempty"`

	// If nonzero, the entire request body up to this size will be read