Rename internal/proxy to internal/servewaf (closes #173)

The package passes nothing to an app since rproxy took that over, so it
is named after the command it serves. Its constructor is New, like
rproxy's. The rproxy tests call their stand-in for servewaf standIn,
since a local servewaf would hide the package. No change of behaviour.

Model: opus-5-5

internal/rproxy/servewaf.go

@@ -11,7 +11,7 @@ import (
 	"net/http"
 	"strings"
 
-	"sneak.berlin/go/smallwebwaf/internal/proxy"
+	"sneak.berlin/go/smallwebwaf/internal/servewaf"
 )
 
 // answerBodyMaxBytes is the most of the body of servewaf's answer that is read.
@@ -38,10 +38,10 @@ type servewafAnswer struct {
 // notes nothing, and no report is due for it: servewaf holds no decision to report
 // on.
 func (rq *request) noteAnswer(answer *servewafAnswer) {
-	disposition := answer.header.Get(proxy.DispositionHeader)
+	disposition := answer.header.Get(servewaf.DispositionHeader)
 
 	switch disposition {
-	case proxy.DispositionAllow, proxy.DispositionDeny, proxy.DispositionClose:
+	case servewaf.DispositionAllow, servewaf.DispositionDeny, servewaf.DispositionClose:
 		rq.disposition = disposition
 		rq.answered = true
 		rq.asn = answer.header.Get(asnHeader)
@@ -74,7 +74,7 @@ func (rq *request) handleNoUsableAnswer(ctx context.Context, err error) {
 		rq.disposition = rq.h.config.DefaultDisposition
 		rq.byDefault = true
 
-		if rq.disposition == proxy.DispositionAllow {
+		if rq.disposition == servewaf.DispositionAllow {
 			rq.passToApp(ctx)
 		} else {
 			rq.answer(http.StatusServiceUnavailable)
@@ -169,13 +169,13 @@ func (rq *request) newQuestion(ctx context.Context) (*http.Request, error) {
 	question.TransferEncoding = in.TransferEncoding
 
 	question.Header = in.Header.Clone()
-	question.Header.Set(proxy.ClientHeader, rq.client.String())
-	question.Header.Set(proxy.PeerHeader, rq.peer.String())
-	question.Header.Del(proxy.ContentLengthHeader)
+	question.Header.Set(servewaf.ClientHeader, rq.client.String())
+	question.Header.Set(servewaf.PeerHeader, rq.peer.String())
+	question.Header.Del(servewaf.ContentLengthHeader)
 
 	announced := in.Header.Get("Content-Length")
 	if announced != "" {
-		question.Header.Set(proxy.ContentLengthHeader, announced)
+		question.Header.Set(servewaf.ContentLengthHeader, announced)
 	}
 
 	question.Header.Set(requestIDHeader, rq.id)
@@ -196,7 +196,7 @@ func (rq *request) answerWith(answer *servewafAnswer) {
 
 	header := rq.out.Header()
 	maps.Copy(header, answer.header)
-	header.Del(proxy.DispositionHeader)
+	header.Del(servewaf.DispositionHeader)
 
 	// Go's server adds a Content-Type it guesses from the body to a response whose
 	// headers have no Content-Type key. The key with no value sends none.
@@ -210,7 +210,7 @@ func (rq *request) answerWith(answer *servewafAnswer) {
 // sendReport sends servewaf report on a goroutine of its own, so that the
 // visitor does not wait for it. The report goes on after ctx, the request's own
 // context, has ended.
-func (h *handler) sendReport(ctx context.Context, report *proxy.Report) {
+func (h *handler) sendReport(ctx context.Context, report *servewaf.Report) {
 	h.reportsMu.Lock()
 	defer h.reportsMu.Unlock()
 
@@ -228,7 +228,7 @@ func (h *handler) sendReport(ctx context.Context, report *proxy.Report) {
 
 // postReport posts report to servewaf, and waits for its answer for up to
 // SWRP_TIMEOUT_MS.
-func (h *handler) postReport(ctx context.Context, report *proxy.Report) error {
+func (h *handler) postReport(ctx context.Context, report *servewaf.Report) error {
 	body, err := json.Marshal(report)
 	if err != nil {
 		return fmt.Errorf("encode the report: %w", err)