Finish the depencency reader

sls_store/sls_dependency_reader.go

@@ -4,14 +4,63 @@ import (
 	"context"
 	slsSdk "github.com/aliyun/aliyun-log-go-sdk"
 	"github.com/jaegertracing/jaeger/model"
+	"strconv"
 	"time"
 )
 
+const (
+	// DependenciesQueryString The query string which calculates the dependency relationship between each service.
+	DependenciesQueryString = "* and version: service_name"
+
+	// ParentServiceFieldName The log item key of parent service name
+	ParentServiceFieldName = "parent_service"
+	// FailureCallingTimesFieldName The key of failure calling times
+	FailureCallingTimesFieldName = "n_status_fail"
+	// SuccessfulCallingTimesFieldName The key of successful calling times
+	SuccessfulCallingTimesFieldName = "n_status_succ"
+	// ParentService the key of parent service
+	ParentService = "parent_service"
+	// ChildService the key of child service
+	ChildService = "child_service"
+)
+
 type slsDependencyReader struct {
 	client   *slsSdk.Client
 	instance slsTraceInstance
 }
 
 func (s slsDependencyReader) GetDependencies(ctx context.Context, endTs time.Time, lookback time.Duration) ([]model.DependencyLink, error) {
-	return nil, nil
+	response, error := s.client.GetLogs(s.instance.project(), s.instance.serviceDependencyLogStore(), "",
+		endTs.Unix()-int64(lookback), endTs.Unix(), DependenciesQueryString, 1000, 0, false)
+
+	if error != nil {
+		return nil, error
+	}
+
+	result := make([]model.DependencyLink, response.Count)
+	for i, log := range response.Logs {
+		if log[ParentServiceFieldName] == "None" {
+			continue
+		}
+
+		result[i] = model.DependencyLink{
+			Parent:    log[ParentService],
+			Child:     log[ChildService],
+			CallCount: getCallingTime(log),
+		}
+	}
+
+	return result, nil
+}
+
+func getCallingTime(log map[string]string) uint64 {
+	return getCallingTimes(log, SuccessfulCallingTimesFieldName) + getCallingTimes(log, FailureCallingTimesFieldName)
+}
+
+func getCallingTimes(log map[string]string, key string) uint64 {
+	successCount, e2 := strconv.Atoi(log[key])
+	if e2 != nil {
+		successCount = 0
+	}
+	return uint64(successCount)
 }