update according to review comments

pkg/filter/wasm/hostfunc.go

@@ -32,7 +32,6 @@ import (
 	"github.com/megaease/easegress/pkg/logger"
 )
 
-////////////////////////////////////////////////////////////////////////////////
 // helper functions
 
 const wasmMemory = "memory"
@@ -152,8 +151,7 @@ func (vm *WasmVM) readHeaderFromWasm(addr int32) http.Header {
 	return http.Header(h)
 }
 
-////////////////////////////////////////////////////////////////////////////////
-// request function
+// request functions
 
 func (vm *WasmVM) hostRequestGetRealIP() int32 {
 	v := vm.ctx.Request().RealIP()
@@ -294,7 +292,6 @@ func (vm *WasmVM) hostRequestSetBody(addr int32) {
 	vm.ctx.Request().SetBody(bytes.NewReader(body))
 }
 
-////////////////////////////////////////////////////////////////////////////////
 // response functions
 
 func (vm *WasmVM) hostResponseGetStatusCode() int32 {
@@ -362,7 +359,6 @@ func (vm *WasmVM) hostResponseSetBody(addr int32) {
 	vm.ctx.Response().SetBody(bytes.NewReader(body))
 }
 
-////////////////////////////////////////////////////////////////////////////////
 // misc functions
 
 func (vm *WasmVM) hostAddTag(addr int32) {
@@ -384,8 +380,6 @@ func (vm *WasmVM) hostLog(level int32, addr int32) {
 	}
 }
 
-////////////////////////////////////////////////////////////////////////////////
-
 // importHostFuncs imports host functions into Wasm so that user-developed Wasm
 // code can call these functions to interoperate with host.
 func (vm *WasmVM) importHostFuncs(linker *wasmtime.Linker) {

pkg/filter/wasm/wasm.go

@@ -104,15 +104,6 @@ func (f *WasmFilter) Results() []string {
 	return results
 }
 
-func readWasmCodeFromFile(path string) ([]byte, error) {
-	f, e := os.Open(path)
-	if e != nil {
-		return nil, e
-	}
-	defer f.Close()
-	return io.ReadAll(f)
-}
-
 func readWasmCodeFromURL(url string) ([]byte, error) {
 	resp, e := http.DefaultClient.Get(url)
 	if e != nil {
@@ -127,8 +118,7 @@ func isURL(str string) bool {
 	// the LONG base64 encoded wasm code
 	for _, p := range []string{"http://", "https://"} {
 		if len(str) > len(p) {
-			s := strings.ToLower(str[:len(p)])
-			if strings.HasPrefix(s, p) {
+			if p == strings.ToLower(str[:len(p)]) {
 				return true
 			}
 		}
@@ -141,7 +131,7 @@ func (f *WasmFilter) readWasmCode() ([]byte, error) {
 		return readWasmCodeFromURL(f.spec.Code)
 	}
 	if _, e := os.Stat(f.spec.Code); e == nil {
-		return readWasmCodeFromFile(f.spec.Code)
+		return os.ReadFile(f.spec.Code)
 	}
 	return base64.StdEncoding.DecodeString(f.spec.Code)
 }