67 lines
1.3 KiB
Go
67 lines
1.3 KiB
Go
package hijack
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import (
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"bufio"
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"net"
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"net/http"
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"sync"
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)
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func New(w http.ResponseWriter, commit func(http.ResponseWriter)) (http.ResponseWriter, func()) {
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responseWriter := &responseWriter{
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commit: commit,
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w: w,
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}
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if _, ok := w.(http.Hijacker); ok {
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return &responseWriterHijacker{
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responseWriter: responseWriter,
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}, responseWriter.ensureCommitted
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} else {
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return responseWriter, responseWriter.ensureCommitted
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}
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}
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var _ http.ResponseWriter = new(responseWriter)
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var _ http.ResponseWriter = new(responseWriterHijacker)
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var _ http.Hijacker = new(responseWriterHijacker)
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type responseWriter struct {
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commit func(http.ResponseWriter)
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w http.ResponseWriter
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hijacked bool
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writeOnce sync.Once
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}
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func (rw *responseWriter) ensureCommitted() {
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rw.writeOnce.Do(func() {
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if rw.hijacked {
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return
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}
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rw.commit(rw.w)
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})
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}
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func (rw *responseWriter) Header() http.Header {
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return rw.w.Header()
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}
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func (rw *responseWriter) Write(data []byte) (int, error) {
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rw.ensureCommitted()
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return rw.w.Write(data)
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}
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func (rw *responseWriter) WriteHeader(status int) {
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rw.ensureCommitted()
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rw.w.WriteHeader(status)
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}
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type responseWriterHijacker struct {
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*responseWriter
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}
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func (rw *responseWriterHijacker) Hijack() (net.Conn, *bufio.ReadWriter, error) {
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rw.hijacked = true
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return rw.w.(http.Hijacker).Hijack()
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}
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