diff --git a/src/testdata/http.go b/src/testdata/http.go
index 7255628..6d65c91 100644
--- a/src/testdata/http.go
+++ b/src/testdata/http.go
@@ -1,6 +1,8 @@
 package main
 
 import (
+	"io"
+	"log"
 	"net/http"
 	"os"
 )
@@ -8,7 +10,13 @@ import (
 func main() {
 	p := os.Getenv("PORT")
 	if err := http.ListenAndServe(":"+p, http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		w.Write([]byte(os.Getenv("BODY")))
+		b, _ := io.ReadAll(r.Body)
+		log.Printf("> %s", b)
+		body := os.Getenv("BODY")
+		if body == "-" {
+			body = string(b)
+		}
+		w.Write([]byte(body))
 	})); err != nil {
 		panic(err)
 	}