add gc-test plugin (#597)

plugins/wasm-go/extensions/gc-test/main.go

@@ -0,0 +1,39 @@
+package main
+
+import (
+	"fmt"
+	"runtime"
+
+	. "github.com/alibaba/higress/plugins/wasm-go/pkg/wrapper"
+	"github.com/tetratelabs/proxy-wasm-go-sdk/proxywasm"
+	"github.com/tetratelabs/proxy-wasm-go-sdk/proxywasm/types"
+	"github.com/tidwall/gjson"
+)
+
+func main() {
+	SetCtx(
+		"gc-test",
+		ParseConfigBy(parseConfig),
+		ProcessRequestHeadersBy(onHttpRequestHeaders),
+	)
+}
+
+type MyConfig struct {
+	bytes uint64
+}
+
+func parseConfig(json gjson.Result, config *MyConfig, log Log) error {
+	config.bytes = json.Get("bytes").Uint()
+	return nil
+}
+
+func onHttpRequestHeaders(ctx HttpContext, config MyConfig, log Log) types.Action {
+	b := make([]byte, int(config.bytes))
+	var m runtime.MemStats
+	runtime.ReadMemStats(&m)
+	log.Infof("alloc success, point address: %p", b)
+	memstats := fmt.Sprintf(`{"Sys": %d,"HeapSys": %d,"HeapIdle": %d,"HeapInuse": %d,"HeapReleased": %d}`, m.Sys, m.HeapSys, m.HeapIdle, m.HeapInuse, m.HeapReleased)
+	log.Info(memstats)
+	proxywasm.SendHttpResponse(200, [][2]string{{"Content-Type", "application/json"}}, []byte(memstats), -1)
+	return types.ActionContinue
+}