diff options
author | Matthew Holt <mholt@users.noreply.github.com> | 2019-11-15 17:15:33 -0700 |
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committer | Matthew Holt <mholt@users.noreply.github.com> | 2019-11-15 17:15:33 -0700 |
commit | 1228dd7d93b59409fd844400b9c114be267df3a3 (patch) | |
tree | fec39d2abcaba8c2a4cdcdcbb17e39a0c8e905da /modules/caddyhttp/reverseproxy | |
parent | af26a03da1af7cd7d64fc03270961829d0311ed7 (diff) |
reverse_proxy: Allow buffering of client requests
This is a bad idea, but some backends apparently require it. See
discussion in #176.
Diffstat (limited to 'modules/caddyhttp/reverseproxy')
-rw-r--r-- | modules/caddyhttp/reverseproxy/reverseproxy.go | 51 | ||||
-rw-r--r-- | modules/caddyhttp/reverseproxy/streaming.go | 1 |
2 files changed, 39 insertions, 13 deletions
diff --git a/modules/caddyhttp/reverseproxy/reverseproxy.go b/modules/caddyhttp/reverseproxy/reverseproxy.go index 77dc005..98118c2 100644 --- a/modules/caddyhttp/reverseproxy/reverseproxy.go +++ b/modules/caddyhttp/reverseproxy/reverseproxy.go @@ -15,14 +15,18 @@ package reverseproxy import ( + "bytes" "context" "encoding/json" "fmt" + "io" + "io/ioutil" "net" "net/http" "regexp" "strconv" "strings" + "sync" "time" "github.com/caddyserver/caddy/v2" @@ -38,13 +42,14 @@ func init() { // Handler implements a highly configurable and production-ready reverse proxy. type Handler struct { - TransportRaw json.RawMessage `json:"transport,omitempty"` - CBRaw json.RawMessage `json:"circuit_breaker,omitempty"` - LoadBalancing *LoadBalancing `json:"load_balancing,omitempty"` - HealthChecks *HealthChecks `json:"health_checks,omitempty"` - Upstreams UpstreamPool `json:"upstreams,omitempty"` - FlushInterval caddy.Duration `json:"flush_interval,omitempty"` - Headers *headers.Handler `json:"headers,omitempty"` + TransportRaw json.RawMessage `json:"transport,omitempty"` + CBRaw json.RawMessage `json:"circuit_breaker,omitempty"` + LoadBalancing *LoadBalancing `json:"load_balancing,omitempty"` + HealthChecks *HealthChecks `json:"health_checks,omitempty"` + Upstreams UpstreamPool `json:"upstreams,omitempty"` + FlushInterval caddy.Duration `json:"flush_interval,omitempty"` + Headers *headers.Handler `json:"headers,omitempty"` + BufferRequests bool `json:"buffer_requests,omitempty"` Transport http.RoundTripper `json:"-"` CB CircuitBreaker `json:"-"` @@ -222,6 +227,27 @@ func (h *Handler) Cleanup() error { func (h *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request, next caddyhttp.Handler) error { repl := r.Context().Value(caddy.ReplacerCtxKey).(caddy.Replacer) + // if enabled, buffer client request; + // this should only be enabled if the + // upstream requires it and does not + // work with "slow clients" (gunicorn, + // etc.) - this obviously has a perf + // overhead and makes the proxy at + // risk of exhausting memory and more + // suseptible to slowloris attacks, + // so it is strongly recommended to + // only use this feature if absolutely + // required, if read timeouts are set, + // and if body size is limited + if h.BufferRequests { + buf := bufPool.Get().(*bytes.Buffer) + buf.Reset() + defer bufPool.Put(buf) + io.Copy(buf, r.Body) + r.Body.Close() + r.Body = ioutil.NopCloser(buf) + } + // prepare the request for proxying; this is needed only once err := h.prepareRequest(r) if err != nil { @@ -662,12 +688,11 @@ type DialError struct { error } -// TODO: see if we can use this -// var bufPool = sync.Pool{ -// New: func() interface{} { -// return new(bytes.Buffer) -// }, -// } +var bufPool = sync.Pool{ + New: func() interface{} { + return new(bytes.Buffer) + }, +} // Interface guards var ( diff --git a/modules/caddyhttp/reverseproxy/streaming.go b/modules/caddyhttp/reverseproxy/streaming.go index a3b711b..3ab122c 100644 --- a/modules/caddyhttp/reverseproxy/streaming.go +++ b/modules/caddyhttp/reverseproxy/streaming.go @@ -110,6 +110,7 @@ func (h Handler) copyResponse(dst io.Writer, src io.Reader, flushInterval time.D // buf = h.BufferPool.Get() // defer h.BufferPool.Put(buf) // } + // // we could also see about a pool that returns values like this: make([]byte, 32*1024) _, err := h.copyBuffer(dst, src, buf) return err } |