add query demo

example/consumer/query_demo/simple_demo_with_query.go

@@ -0,0 +1,49 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"os/signal"
+	"syscall"
+
+	sls "github.com/aliyun/aliyun-log-go-sdk"
+	consumerLibrary "github.com/aliyun/aliyun-log-go-sdk/consumer"
+	"github.com/go-kit/kit/log/level"
+)
+
+// README :
+// This is a very simple example of pulling data from your logstore and printing it for consumption, including pre-handling for logs.
+
+func main() {
+	option := consumerLibrary.LogHubConfig{
+		Endpoint:          "",
+		AccessKeyID:       "",
+		AccessKeySecret:   "",
+		Project:           "",
+		Logstore:          "",
+		ConsumerGroupName: "",
+		ConsumerName:      "",
+		// This options is used for initialization, will be ignored once consumer group is created and each shard has been started to be consumed.
+		// Could be "begin", "end", "specific time format in time stamp", it's log receiving time.
+		CursorPosition: consumerLibrary.BEGIN_CURSOR,
+		// Query is for log pre-handling before return to client, more info refer to https://help.aliyun.com/zh/sls/user-guide/rule-based-consumption
+		Query: "* | where cast(body_bytes_sent as bigint) > 14000",
+	}
+
+	consumerWorker := consumerLibrary.InitConsumerWorkerWithCheckpointTracker(option, process)
+	ch := make(chan os.Signal, 1)
+	signal.Notify(ch, syscall.SIGINT, syscall.SIGTERM)
+	consumerWorker.Start()
+	if _, ok := <-ch; ok {
+		level.Info(consumerWorker.Logger).Log("msg", "get stop signal, start to stop consumer worker", "consumer worker name", option.ConsumerName)
+		consumerWorker.StopAndWait()
+	}
+}
+
+// Fill in your consumption logic here, and be careful not to change the parameters of the function and the return value,
+// otherwise you will report errors.
+func process(shardId int, logGroupList *sls.LogGroupList, checkpointTracker consumerLibrary.CheckPointTracker) (string, error) {
+	fmt.Println(shardId, logGroupList)
+	checkpointTracker.SaveCheckPoint(false)
+	return "", nil
+}