dataproxy: added caching of datasources when doing data proxy requests, #9078

pkg/api/api.go

@@ -217,8 +217,8 @@ func (hs *HttpServer) registerRoutes() {
 		}, reqOrgAdmin)
 
 		r.Get("/frontend/settings/", GetFrontendSettings)
-		r.Any("/datasources/proxy/:id/*", reqSignedIn, ProxyDataSourceRequest)
-		r.Any("/datasources/proxy/:id", reqSignedIn, ProxyDataSourceRequest)
+		r.Any("/datasources/proxy/:id/*", reqSignedIn, hs.ProxyDataSourceRequest)
+		r.Any("/datasources/proxy/:id", reqSignedIn, hs.ProxyDataSourceRequest)
 
 		// Dashboard
 		r.Group("/dashboards", func() {

pkg/api/dataproxy.go

@@ -1,6 +1,9 @@
 package api
 
 import (
+	"fmt"
+	"time"
+
 	"github.com/grafana/grafana/pkg/api/pluginproxy"
 	"github.com/grafana/grafana/pkg/bus"
 	"github.com/grafana/grafana/pkg/metrics"
@@ -9,19 +12,35 @@ import (
 	"github.com/grafana/grafana/pkg/plugins"
 )
 
-func getDatasource(id int64, orgId int64) (*m.DataSource, error) {
+const HeaderNameNoBackendCache = "X-Grafana-NoCache"
+
+func (hs *HttpServer) getDatasourceById(id int64, orgId int64, nocache bool) (*m.DataSource, error) {
+	cacheKey := fmt.Sprintf("ds-%d", id)
+
+	if !nocache {
+		if cached, found := hs.cache.Get(cacheKey); found {
+			ds := cached.(*m.DataSource)
+			if ds.OrgId == orgId {
+				return ds, nil
+			}
+		}
+	}
+
 	query := m.GetDataSourceByIdQuery{Id: id, OrgId: orgId}
 	if err := bus.Dispatch(&query); err != nil {
 		return nil, err
 	}
 
+	hs.cache.Set(cacheKey, query.Result, time.Second*5)
 	return query.Result, nil
 }
 
-func ProxyDataSourceRequest(c *middleware.Context) {
+func (hs *HttpServer) ProxyDataSourceRequest(c *middleware.Context) {
 	c.TimeRequest(metrics.M_DataSource_ProxyReq_Timer)
 
-	ds, err := getDatasource(c.ParamsInt64(":id"), c.OrgId)
+	nocache := c.Req.Header.Get(HeaderNameNoBackendCache) == "true"
+
+	ds, err := hs.getDatasourceById(c.ParamsInt64(":id"), c.OrgId, nocache)
 
 	if err != nil {
 		c.JsonApiErr(500, "Unable to load datasource meta data", err)

pkg/api/http_server.go

@@ -9,7 +9,9 @@ import (
 	"net/http"
 	"os"
 	"path"
+	"time"
 
+	gocache "github.com/patrickmn/go-cache"
 	macaron "gopkg.in/macaron.v1"
 
 	"github.com/grafana/grafana/pkg/api/live"
@@ -29,13 +31,15 @@ type HttpServer struct {
 	macaron       *macaron.Macaron
 	context       context.Context
 	streamManager *live.StreamManager
+	cache         *gocache.Cache
 
 	httpSrv *http.Server
 }
 
 func NewHttpServer() *HttpServer {
 	return &HttpServer{
-		log: log.New("http.server"),
+		log:   log.New("http.server"),
+		cache: gocache.New(5*time.Minute, 10*time.Minute),
 	}
 }