Files
tesseract/internal/reverseproxy/proxy.go
2024-11-12 00:31:10 +00:00

134 lines
2.6 KiB
Go

package reverseproxy
import (
"fmt"
"github.com/labstack/echo/v4"
"net/http"
"net/http/httputil"
"net/url"
"regexp"
"strings"
"tesseract/internal/service"
)
type ReverseProxy struct {
*echo.Echo
services service.Services
httpProxies map[string]*httputil.ReverseProxy
}
type portMapping struct {
subdomain string
containerPort int
hostPort int
}
const keyReverseProxy = "reverseProxy"
func New(services service.Services) *ReverseProxy {
e := echo.New()
proxy := &ReverseProxy{
e,
services,
make(map[string]*httputil.ReverseProxy),
}
e.Any("/*", proxy.handleRequest)
return proxy
}
func From(c echo.Context) *ReverseProxy {
return c.Get(keyReverseProxy).(*ReverseProxy)
}
func (p *ReverseProxy) Start() error {
rows, err := p.services.Database.Query("SELECT container_port, host_port, subdomain FROM port_mappings;")
if err != nil {
return err
}
defer rows.Close()
var mappings []portMapping
for rows.Next() {
mapping := portMapping{}
err = rows.Scan(&mapping.containerPort, &mapping.hostPort, &mapping.subdomain)
if err != nil {
return err
}
}
for _, m := range mappings {
if m.subdomain == "" {
continue
}
u, err := url.Parse(fmt.Sprintf("http://localhost:%d", m.hostPort))
if err != nil {
continue
}
proxy := httputil.NewSingleHostReverseProxy(u)
p.httpProxies[m.subdomain] = proxy
}
return nil
}
func (p *ReverseProxy) Middleware() echo.MiddlewareFunc {
return func(next echo.HandlerFunc) echo.HandlerFunc {
return func(c echo.Context) error {
c.Set(keyReverseProxy, p)
return next(c)
}
}
}
func (p *ReverseProxy) ShouldHandleRequest(c echo.Context) bool {
config := p.services.Config
h := strings.Replace(config.HostName, ".", "\\.", -1)
reg, err := regexp.Compile(".*\\." + h)
if err != nil {
return false
}
return reg.MatchString(c.Request().Host)
}
func (p *ReverseProxy) handleRequest(c echo.Context) error {
req := c.Request()
res := c.Response()
config := p.services.Config
h := strings.Replace(config.HostName, ".", "\\.", -1)
reg, err := regexp.Compile(fmt.Sprintf("(?P<subdomain>.*)\\.%v", h))
if err != nil {
return err
}
matches := reg.FindStringSubmatch(req.Host)
if len(matches) == 0 {
return echo.NewHTTPError(http.StatusNotFound)
}
var subdomain string
for i, name := range reg.SubexpNames() {
if i != 0 && name == "subdomain" {
subdomain = matches[i]
break
}
}
if subdomain == "" {
return echo.NewHTTPError(http.StatusNotFound)
}
proxy, ok := p.httpProxies[subdomain]
if !ok {
return echo.NewHTTPError(http.StatusNotFound)
}
proxy.ServeHTTP(res, req)
return nil
}