bouncer/internal/proxy/director/layer/rewriter/api.go

80 lines
1.5 KiB
Go

package rewriter
import (
"context"
"fmt"
"forge.cadoles.com/cadoles/bouncer/internal/rule"
"github.com/expr-lang/expr"
"github.com/pkg/errors"
)
type errRedirect struct {
statusCode int
url string
}
func (e *errRedirect) StatusCode() int {
return e.statusCode
}
func (e *errRedirect) URL() string {
return e.url
}
func (e *errRedirect) Error() string {
return fmt.Sprintf("redirect %d %s", e.statusCode, e.url)
}
func newErrRedirect(statusCode int, url string) *errRedirect {
return &errRedirect{
url: url,
statusCode: statusCode,
}
}
var _ error = &errRedirect{}
func redirectFunc() expr.Option {
return expr.Function(
"redirect",
func(params ...any) (any, error) {
_, err := rule.Assert[context.Context](params[0])
if err != nil {
return nil, errors.WithStack(err)
}
statusCode, err := rule.Assert[int](params[1])
if err != nil {
return nil, errors.WithStack(err)
}
if statusCode < 300 || statusCode >= 400 {
return nil, errors.Errorf("unexpected redirect status code '%d'", statusCode)
}
url, err := rule.Assert[string](params[2])
if err != nil {
return nil, errors.WithStack(err)
}
return nil, newErrRedirect(statusCode, url)
},
new(func(context.Context, int, string) bool),
)
}
func WithRewriterFuncs() rule.OptionFunc {
return func(opts *rule.Options) {
funcs := []expr.Option{
redirectFunc(),
}
if len(opts.Expr) == 0 {
opts.Expr = make([]expr.Option, 0)
}
opts.Expr = append(opts.Expr, funcs...)
}
}