mirror of
https://github.com/caddyserver/caddy.git
synced 2024-11-29 20:24:11 +08:00
126 lines
3.5 KiB
Go
126 lines
3.5 KiB
Go
// Package gzip provides a middleware layer that performs
|
|
// gzip compression on the response.
|
|
package gzip
|
|
|
|
import (
|
|
"io"
|
|
"net/http"
|
|
"strings"
|
|
|
|
"github.com/mholt/caddy"
|
|
"github.com/mholt/caddy/caddyhttp/httpserver"
|
|
)
|
|
|
|
func init() {
|
|
caddy.RegisterPlugin("gzip", caddy.Plugin{
|
|
ServerType: "http",
|
|
Action: setup,
|
|
})
|
|
|
|
initWriterPool()
|
|
}
|
|
|
|
// Gzip is a middleware type which gzips HTTP responses. It is
|
|
// imperative that any handler which writes to a gzipped response
|
|
// specifies the Content-Type, otherwise some clients will assume
|
|
// application/x-gzip and try to download a file.
|
|
type Gzip struct {
|
|
Next httpserver.Handler
|
|
Configs []Config
|
|
}
|
|
|
|
// Config holds the configuration for Gzip middleware
|
|
type Config struct {
|
|
RequestFilters []RequestFilter
|
|
ResponseFilters []ResponseFilter
|
|
Level int // Compression level
|
|
}
|
|
|
|
// ServeHTTP serves a gzipped response if the client supports it.
|
|
func (g Gzip) ServeHTTP(w http.ResponseWriter, r *http.Request) (int, error) {
|
|
if !strings.Contains(r.Header.Get("Accept-Encoding"), "gzip") {
|
|
return g.Next.ServeHTTP(w, r)
|
|
}
|
|
outer:
|
|
for _, c := range g.Configs {
|
|
|
|
// Check request filters to determine if gzipping is permitted for this request
|
|
for _, filter := range c.RequestFilters {
|
|
if !filter.ShouldCompress(r) {
|
|
continue outer
|
|
}
|
|
}
|
|
|
|
// gzipWriter modifies underlying writer at init,
|
|
// use a discard writer instead to leave ResponseWriter in
|
|
// original form.
|
|
gzipWriter := getWriter(c.Level)
|
|
defer putWriter(c.Level, gzipWriter)
|
|
gz := &gzipResponseWriter{
|
|
Writer: gzipWriter,
|
|
ResponseWriterWrapper: &httpserver.ResponseWriterWrapper{ResponseWriter: w},
|
|
}
|
|
|
|
var rw http.ResponseWriter
|
|
// if no response filter is used
|
|
if len(c.ResponseFilters) == 0 {
|
|
// replace discard writer with ResponseWriter
|
|
gzipWriter.Reset(w)
|
|
rw = gz
|
|
} else {
|
|
// wrap gzip writer with ResponseFilterWriter
|
|
rw = NewResponseFilterWriter(c.ResponseFilters, gz)
|
|
}
|
|
|
|
// Any response in forward middleware will now be compressed
|
|
status, err := g.Next.ServeHTTP(rw, r)
|
|
|
|
// If there was an error that remained unhandled, we need
|
|
// to send something back before gzipWriter gets closed at
|
|
// the return of this method!
|
|
if status >= 400 {
|
|
httpserver.DefaultErrorFunc(w, r, status)
|
|
return 0, err
|
|
}
|
|
return status, err
|
|
}
|
|
|
|
// no matching filter
|
|
return g.Next.ServeHTTP(w, r)
|
|
}
|
|
|
|
// gzipResponeWriter wraps the underlying Write method
|
|
// with a gzip.Writer to compress the output.
|
|
type gzipResponseWriter struct {
|
|
io.Writer
|
|
*httpserver.ResponseWriterWrapper
|
|
statusCodeWritten bool
|
|
}
|
|
|
|
// WriteHeader wraps the underlying WriteHeader method to prevent
|
|
// problems with conflicting headers from proxied backends. For
|
|
// example, a backend system that calculates Content-Length would
|
|
// be wrong because it doesn't know it's being gzipped.
|
|
func (w *gzipResponseWriter) WriteHeader(code int) {
|
|
w.Header().Del("Content-Length")
|
|
w.Header().Set("Content-Encoding", "gzip")
|
|
w.Header().Add("Vary", "Accept-Encoding")
|
|
w.ResponseWriterWrapper.WriteHeader(code)
|
|
w.statusCodeWritten = true
|
|
}
|
|
|
|
// Write wraps the underlying Write method to do compression.
|
|
func (w *gzipResponseWriter) Write(b []byte) (int, error) {
|
|
if w.Header().Get("Content-Type") == "" {
|
|
w.Header().Set("Content-Type", http.DetectContentType(b))
|
|
}
|
|
if !w.statusCodeWritten {
|
|
w.WriteHeader(http.StatusOK)
|
|
}
|
|
n, err := w.Writer.Write(b)
|
|
return n, err
|
|
}
|
|
|
|
// Interface guards
|
|
var _ httpserver.HTTPInterfaces = (*gzipResponseWriter)(nil)
|