Add ConvertNetHttpRequestToFastHttpRequest adaptor function

fasthttpadaptor/request.go

@@ -3,6 +3,8 @@
 import (
 	"bytes"
 	"io"
+	"math"
+	"net"
 	"net/http"
 	"net/url"
 	"strings"
@@ -68,3 +70,72 @@
 
 	return nil
 }
+
+// ConvertNetHttpRequestToFastHttpRequest converts an http.Request to a fasthttp.RequestCtx.
+//
+// The caller is responsible for the lifecycle of the fasthttp.RequestCtx and the
+// underlying fasthttp.Request. The ctx (and its Request) must only be used for
+// the duration that fasthttp considers it valid (typically within a handler),
+// and must not be accessed after the handler has returned.
+//
+// The request body is not copied. If r.Body is non-nil, it is passed directly to
+// ctx.Request via SetBodyStream. This means:
+//   - r.Body must remain readable for as long as ctx may need to read it.
+//   - r.Body should not be read from, written to, or closed by the caller until
+//     fasthttp is done with ctx.
+//   - The same r.Body must not be reused concurrently in other goroutines while
+//     it is attached to ctx.Request.
+//
+// After calling this function, you should treat r.Body as effectively owned by
+// ctx.Request for the lifetime of that context.
+func ConvertNetHttpRequestToFastHttpRequest(r *http.Request, ctx *fasthttp.RequestCtx) {
+	ctx.Request.Header.SetMethod(r.Method)
+
+	if r.RequestURI != "" {
+		ctx.Request.SetRequestURI(r.RequestURI)
+	} else if r.URL != nil {
+		ctx.Request.SetRequestURI(r.URL.RequestURI())
+	}
+
+	ctx.Request.Header.SetProtocol(r.Proto)
+	ctx.Request.SetHost(r.Host)
+
+	for k, values := range r.Header {
+		for i, v := range values {
+			if i == 0 {
+				ctx.Request.Header.Set(k, v)
+			} else {
+				ctx.Request.Header.Add(k, v)
+			}
+		}
+	}
+
+	if r.Body != nil {
+		contentLength := int(r.ContentLength)
+		if r.ContentLength >= int64(math.MaxInt) {
+			contentLength = -1
+		}
+
+		ctx.Request.SetBodyStream(r.Body, contentLength)
+	}
+
+	if r.RemoteAddr != "" {
+		addr := parseRemoteAddr(r.RemoteAddr)
+		ctx.SetRemoteAddr(addr)
+	}
+}
+
+func parseRemoteAddr(addr string) net.Addr {
+	if tcpAddr, err := net.ResolveTCPAddr("tcp", addr); err == nil {
+		return tcpAddr
+	}
+
+	if _, _, err := net.SplitHostPort(addr); err != nil {
+		if tcpAddr, err := net.ResolveTCPAddr("tcp", net.JoinHostPort(addr, "0")); err == nil {
+			return tcpAddr
+		}
+	}
+
+	host := strings.Trim(addr, "[]")
+	return &net.TCPAddr{IP: net.ParseIP(host)}
+}