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package util
import (
"bytes"
"fmt"
"log"
"net/http"
"runtime"
"strconv"
)
type httpResponseBuffer struct {
inner http.ResponseWriter
buf bytes.Buffer
status int
}
func (o *httpResponseBuffer) Header() http.Header {
return o.inner.Header()
}
func (o *httpResponseBuffer) Write(data []byte) (int, error) {
return o.buf.Write(data)
}
func (o *httpResponseBuffer) WriteHeader(status int) {
o.status = status
}
type SaneHTTPHandler struct {
Inner http.Handler
}
func (h SaneHTTPHandler) ServeHTTP(out http.ResponseWriter, in *http.Request) {
HTTPHandlerFuncWrapper(out, in, h.Inner.ServeHTTP)
}
func HTTPHandlerFuncWrapper(out http.ResponseWriter, in *http.Request, fn http.HandlerFunc) {
buf := httpResponseBuffer{
inner: out,
status: http.StatusOK,
}
ok := true
func() {
defer func() {
if r := recover(); r != nil {
const size = 64 << 10
buf := make([]byte, size)
buf = buf[:runtime.Stack(buf, false)]
st := fmt.Sprintf("%[1]T(%#[1]v) => %[1]v\n\n%[2]s", r, string(buf))
log.Printf("panic serving %v\n\n%s", in.URL, st)
http.Error(out, fmt.Sprintf("500 Internal Server Error:\n\n%s", st), 500)
ok = false
}
}()
fn(&buf, in)
}()
if ok {
out.Header().Set("Content-Length", strconv.Itoa(buf.buf.Len()))
out.WriteHeader(buf.status)
buf.buf.WriteTo(out)
}
}
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