feat: rewriter layer

internal/proxy/director/layer/rewriter/rules.go

@@ -0,0 +1,133 @@
+package rewriter
+
+import (
+	"net/http"
+
+	"forge.cadoles.com/cadoles/bouncer/internal/rule"
+	ruleHTTP "forge.cadoles.com/cadoles/bouncer/internal/rule/http"
+	"github.com/pkg/errors"
+)
+
+type RequestEnv struct {
+	Request RequestInfo `expr:"request"`
+}
+
+type RequestInfo struct {
+	Method           string              `expr:"method"`
+	URL              string              `expr:"url"`
+	Proto            string              `expr:"proto"`
+	ProtoMajor       int                 `expr:"protoMajor"`
+	ProtoMinor       int                 `expr:"protoMinor"`
+	Header           map[string][]string `expr:"header"`
+	ContentLength    int64               `expr:"contentLength"`
+	TransferEncoding []string            `expr:"transferEncoding"`
+	Host             string              `expr:"host"`
+	Trailer          map[string][]string `expr:"trailer"`
+	RemoteAddr       string              `expr:"remoteAddr"`
+	RequestURI       string              `expr:"requestUri"`
+}
+
+func (l *Layer) applyRequestRules(r *http.Request, options *LayerOptions) error {
+	rules := options.Rules.Request
+	if len(rules) == 0 {
+		return nil
+	}
+
+	engine, err := rule.NewEngine[*RequestEnv](
+		ruleHTTP.WithRequestFuncs(r),
+		rule.WithRules(options.Rules.Request...),
+	)
+	if err != nil {
+		return errors.WithStack(err)
+	}
+
+	env := &RequestEnv{
+		Request: RequestInfo{
+			Method:           r.Method,
+			URL:              r.URL.String(),
+			Proto:            r.Proto,
+			ProtoMajor:       r.ProtoMajor,
+			ProtoMinor:       r.ProtoMinor,
+			Header:           r.Header,
+			ContentLength:    r.ContentLength,
+			TransferEncoding: r.TransferEncoding,
+			Host:             r.Host,
+			Trailer:          r.Trailer,
+			RemoteAddr:       r.RemoteAddr,
+			RequestURI:       r.RequestURI,
+		},
+	}
+
+	if _, err := engine.Apply(env); err != nil {
+		return errors.WithStack(err)
+	}
+
+	return nil
+}
+
+type ResponseEnv struct {
+	Request  RequestInfo  `expr:"request"`
+	Response ResponseInfo `expr:"response"`
+}
+
+type ResponseInfo struct {
+	Status           string              `expr:"status"`
+	StatusCode       int                 `expr:"statusCode"`
+	Proto            string              `expr:"proto"`
+	ProtoMajor       int                 `expr:"protoMajor"`
+	ProtoMinor       int                 `expr:"protoMinor"`
+	Header           map[string][]string `expr:"header"`
+	ContentLength    int64               `expr:"contentLength"`
+	TransferEncoding []string            `expr:"transferEncoding"`
+	Uncompressed     bool                `expr:"uncompressed"`
+	Trailer          map[string][]string `expr:"trailer"`
+}
+
+func (l *Layer) applyResponseRules(r *http.Response, options *LayerOptions) error {
+	rules := options.Rules.Request
+	if len(rules) == 0 {
+		return nil
+	}
+
+	engine, err := rule.NewEngine[*ResponseEnv](
+		rule.WithRules(options.Rules.Response...),
+		ruleHTTP.WithResponseFuncs(r),
+	)
+	if err != nil {
+		return errors.WithStack(err)
+	}
+
+	env := &ResponseEnv{
+		Request: RequestInfo{
+			Method:           r.Request.Method,
+			URL:              r.Request.URL.String(),
+			Proto:            r.Request.Proto,
+			ProtoMajor:       r.Request.ProtoMajor,
+			ProtoMinor:       r.Request.ProtoMinor,
+			Header:           r.Request.Header,
+			ContentLength:    r.Request.ContentLength,
+			TransferEncoding: r.Request.TransferEncoding,
+			Host:             r.Request.Host,
+			Trailer:          r.Request.Trailer,
+			RemoteAddr:       r.Request.RemoteAddr,
+			RequestURI:       r.Request.RequestURI,
+		},
+		Response: ResponseInfo{
+			Proto:            r.Proto,
+			ProtoMajor:       r.ProtoMajor,
+			ProtoMinor:       r.ProtoMinor,
+			Header:           r.Header,
+			ContentLength:    r.ContentLength,
+			TransferEncoding: r.TransferEncoding,
+			Trailer:          r.Trailer,
+			Status:           r.Status,
+			StatusCode:       r.StatusCode,
+		},
+	}
+
+	if _, err := engine.Apply(env); err != nil {
+		return errors.WithStack(err)
+	}
+
+	return nil
+}