zry-go-program-framework/websubsvc/frontend_proxy.go

package websubsvc

import (
	"fmt"
	"github.com/gin-gonic/gin"
	"github.com/yhat/wsutil"
	"net/http/httputil"
	"net/url"
)

type FrontendProxy struct {
	debugRedirectNotFoundURLhttp *url.URL
	debugRedirectNotFoundURLws   *url.URL
}

func NewFrontendProxy(proxyURL string) (*FrontendProxy, error) {
	rurl, err := url.Parse(proxyURL)
	if err != nil {
		return nil, fmt.Errorf("invalid proxy url: %w", err)
	}
	rurl4ws, err := url.Parse(proxyURL)
	if err != nil {
		return nil, fmt.Errorf("invalid proxy url: %w", err)
	}
	if rurl4ws.Scheme == "https" {
		rurl4ws.Scheme = "wss"
	} else {
		rurl4ws.Scheme = "ws"
	}
	return &FrontendProxy{
		debugRedirectNotFoundURLhttp: rurl,
		debugRedirectNotFoundURLws:   rurl4ws,
	}, nil
}

func (p *FrontendProxy) RedirectNotFoundHandler(context *gin.Context) {
	if context.IsWebsocket() {
		if p.debugRedirectNotFoundURLws == nil {
			return
		}
		proxy := wsutil.NewSingleHostReverseProxy(p.debugRedirectNotFoundURLws)
		proxy.ServeHTTP(context.Writer, context.Request)
	} else {
		if p.debugRedirectNotFoundURLhttp == nil {
			return
		}
		proxy := httputil.NewSingleHostReverseProxy(p.debugRedirectNotFoundURLhttp)
		proxy.ServeHTTP(context.Writer, context.Request)
	}
}