bouncer/internal/rule/http/request.go

package http

import (
	"fmt"
	"net/http"
	"net/url"
	"strconv"
	"strings"
	"time"

	"forge.cadoles.com/Cadoles/go-proxy/wildcard"
	"github.com/expr-lang/expr"
	"github.com/pkg/errors"
)

func setRequestHostFunc(r *http.Request) expr.Option {
	return expr.Function(
		"set_host",
		func(params ...any) (any, error) {
			host := params[0].(string)
			r.Host = host

			return true, nil
		},
		new(func(string) bool),
	)
}

func setRequestURL(r *http.Request) expr.Option {
	return expr.Function(
		"set_url",
		func(params ...any) (any, error) {
			rawURL := params[0].(string)

			url, err := url.Parse(rawURL)
			if err != nil {
				return false, errors.WithStack(err)
			}

			r.URL = url

			return true, nil
		},
		new(func(string) bool),
	)
}

func addRequestHeaderFunc(r *http.Request) expr.Option {
	return expr.Function(
		"add_header",
		func(params ...any) (any, error) {
			name := params[0].(string)
			rawValue := params[1]

			var value string
			switch v := rawValue.(type) {
			case []string:
				value = strings.Join(v, ",")
			case time.Time:
				value = strconv.FormatInt(v.UTC().Unix(), 10)
			case time.Duration:
				value = strconv.FormatInt(int64(v.Seconds()), 10)
			default:
				value = fmt.Sprintf("%v", rawValue)
			}

			r.Header.Add(name, value)

			return true, nil
		},
		new(func(string, string) bool),
	)
}

func setRequestHeaderFunc(r *http.Request) expr.Option {
	return expr.Function(
		"set_header",
		func(params ...any) (any, error) {
			name := params[0].(string)
			rawValue := params[1]

			var value string
			switch v := rawValue.(type) {
			case []string:
				value = strings.Join(v, ",")
			case time.Time:
				value = strconv.FormatInt(v.UTC().Unix(), 10)
			case time.Duration:
				value = strconv.FormatInt(int64(v.Seconds()), 10)
			default:
				value = fmt.Sprintf("%v", rawValue)
			}

			r.Header.Set(name, value)

			return true, nil
		},
		new(func(string, string) bool),
	)
}

func delRequestHeadersFunc(r *http.Request) expr.Option {
	return expr.Function(
		"del_headers",
		func(params ...any) (any, error) {
			pattern := params[0].(string)
			deleted := false

			for key := range r.Header {
				if !wildcard.Match(key, pattern) {
					continue
				}

				r.Header.Del(key)
				deleted = true
			}

			return deleted, nil
		},
		new(func(string) bool),
	)
}