Live: pure websocket push endpoint (#33339)

2021-04-26 13:17:49 +03:00
parent 7f53dfad88
commit 7501a2deb6
9 changed files with 274 additions and 33 deletions
@@ -0,0 +1,111 @@
+package pushhttp
+
+import (
+	"context"
+	"errors"
+	"net/http"
+
+	"github.com/grafana/grafana/pkg/infra/log"
+	"github.com/grafana/grafana/pkg/models"
+	"github.com/grafana/grafana/pkg/registry"
+	"github.com/grafana/grafana/pkg/services/live"
+	"github.com/grafana/grafana/pkg/services/live/convert"
+	"github.com/grafana/grafana/pkg/services/live/pushurl"
+	"github.com/grafana/grafana/pkg/setting"
+)
+
+var (
+	logger = log.New("live.push_http")
+)
+
+func init() {
+	registry.RegisterServiceWithPriority(&Gateway{}, registry.Low)
+}
+
+// Gateway receives data and translates it to Grafana Live publications.
+type Gateway struct {
+	Cfg         *setting.Cfg      `inject:""`
+	GrafanaLive *live.GrafanaLive `inject:""`
+
+	converter *convert.Converter
+}
+
+// Init Gateway.
+func (g *Gateway) Init() error {
+	logger.Info("Telemetry Gateway initialization")
+
+	if !g.IsEnabled() {
+		logger.Debug("Telemetry Gateway not enabled, skipping initialization")
+		return nil
+	}
+
+	g.converter = convert.NewConverter()
+	return nil
+}
+
+// Run Gateway.
+func (g *Gateway) Run(ctx context.Context) error {
+	if !g.IsEnabled() {
+		logger.Debug("GrafanaLive feature not enabled, skipping initialization of Telemetry Gateway")
+		return nil
+	}
+	<-ctx.Done()
+	return ctx.Err()
+}
+
+// IsEnabled returns true if the Grafana Live feature is enabled.
+func (g *Gateway) IsEnabled() bool {
+	return g.Cfg.IsLiveEnabled() // turn on when Live on for now.
+}
+
+func (g *Gateway) Handle(ctx *models.ReqContext) {
+	streamID := ctx.Params(":streamId")
+
+	stream, err := g.GrafanaLive.ManagedStreamRunner.GetOrCreateStream(streamID)
+	if err != nil {
+		logger.Error("Error getting stream", "error", err)
+		ctx.Resp.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+
+	// TODO Grafana 8: decide which formats to use or keep all.
+	urlValues := ctx.Req.URL.Query()
+	frameFormat := pushurl.FrameFormatFromValues(urlValues)
+	stableSchema := pushurl.StableSchemaFromValues(urlValues)
+
+	body, err := ctx.Req.Body().Bytes()
+	if err != nil {
+		logger.Error("Error reading body", "error", err)
+		ctx.Resp.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+	logger.Debug("Live Push request",
+		"protocol", "http",
+		"streamId", streamID,
+		"bodyLength", len(body),
+		"stableSchema", stableSchema,
+		"frameFormat", frameFormat,
+	)
+
+	metricFrames, err := g.converter.Convert(body, frameFormat)
+	if err != nil {
+		logger.Error("Error converting metrics", "error", err, "frameFormat", frameFormat)
+		if errors.Is(err, convert.ErrUnsupportedFrameFormat) {
+			ctx.Resp.WriteHeader(http.StatusBadRequest)
+		} else {
+			ctx.Resp.WriteHeader(http.StatusInternalServerError)
+		}
+		return
+	}
+
+	// TODO -- make sure all packets are combined together!
+	// interval = "1s" vs flush_interval = "5s"
+
+	for _, mf := range metricFrames {
+		err := stream.Push(mf.Key(), mf.Frame(), stableSchema)
+		if err != nil {
+			ctx.Resp.WriteHeader(http.StatusInternalServerError)
+			return
+		}
+	}
+}