Live: support real time measurements (alpha) (#28022)

* improve reduce transformer * add measurment classes * sync with new grafana measure format * use address for live * use plural in URL * set the field name * fix build * find changes * POST http to channel * Yarn: Update lock file (#28014) * Loki: Run instant query only in Explore (#27974) * Run instant query only in Explore * Replace forEach with for loop * don't cast * Docs: Fixed row display in table (#28031) * Plugins: Let descendant plugins inherit their root's signature (#27970) * plugins: Let descendant plugins inherit their root's signature Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com> * Registry: Fix service shutdown mode trigger location (#28025) * Add Alex Khomenko as member (#28032) * show history * fix confirm * fix confirm * add tests * fix lint * add more errors * set values * remove unrelated changes * unrelated changes * Update pkg/models/live.go Co-authored-by: Arve Knudsen <arve.knudsen@gmail.com> * Update pkg/models/live.go Co-authored-by: Arve Knudsen <arve.knudsen@gmail.com> * Update pkg/services/live/live.go Co-authored-by: Arve Knudsen <arve.knudsen@gmail.com> * Update pkg/services/live/pluginHandler.go Co-authored-by: Arve Knudsen <arve.knudsen@gmail.com> * Update pkg/services/live/pluginHandler.go Co-authored-by: Arve Knudsen <arve.knudsen@gmail.com> * Update pkg/services/live/pluginHandler.go Co-authored-by: Arve Knudsen <arve.knudsen@gmail.com> * use measurments for testdata endpoints * add live to testdata * add live to testdata * Update pkg/services/live/channel.go Co-authored-by: Arve Knudsen <arve.knudsen@gmail.com> * Apply suggestions from code review Co-authored-by: Arve Knudsen <arve.knudsen@gmail.com> * update comment formats * uprevert testdata * Apply suggestions from code review Co-authored-by: Will Browne <wbrowne@users.noreply.github.com> Co-authored-by: Ryan McKinley <ryantxu@gmail.com> Co-authored-by: Hugo Häggmark <hugo.haggmark@grafana.com> * Apply suggestions from code review * CloudWatch: Add EC2CapacityReservations Namespace (#28309) * API: Fix short URLs (#28300) * API: Fix short URLs Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com> * Chore: Add cloud-middleware as code owners (#28310) Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com> * SQLStore: Run tests as integration tests (#28265) * sqlstore: Run tests as integration tests * Truncate database instead of re-creating it on each test * Fix test description See https://github.com/grafana/grafana/pull/12129 * Fix lint issues * Fix postgres dialect after review suggestion * Rename and document functions after review suggestion * Add periods * Fix auto-increment value for mysql dialect Co-authored-by: Emil Tullstedt <emil.tullstedt@grafana.com> * Drone: Fix grafana-mixin linting (#28308) * Drone: Fix Starlark script Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com> * grafana-mixin: Move build logic to scripts Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com> * Drone: Use mixin scripts Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com> * CI build image: Install jsonnetfmt and mixtool Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com> * Makefile: Print commands Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com> * should only ignore the file in the grafana mixin root folder (#28306) Signed-off-by: bergquist <carl.bergquist@gmail.com> * fix: for graph size not taking up full height or width * Graph NG: fix toggling queries and extract Graph component from graph3 panel (#28290) * Fix issue when data and config is not in sync * Extract GraphNG component from graph panel and add some tests coverage * Update packages/grafana-ui/src/components/uPlot/hooks.test.ts * Update packages/grafana-ui/src/components/uPlot/hooks.test.ts * Update packages/grafana-ui/src/components/uPlot/hooks.test.ts * Fix grid color and annotations refresh * Drone: Use ${DRONE_TAG} in release pipelines, since it should work (#28299) Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com> * Explore: respect min_refresh_interval (#27988) * Explore: respect min_refresh_interval Fixes #27494 * fixup! Explore: respect min_refresh_interval * fixup! Explore: respect min_refresh_interval * UI: export defaultIntervals from refresh picker * fixup! Explore: respect min_refresh_interval Co-authored-by: Zoltán Bedi <zoltan.bedi@gmail.com> * Loki: Base maxDataPoints limits on query type (#28298) * Base maxLines and maxDataPoints based on query type * Allow overriding the limit to higher value * Bump tree-kill from 1.2.1 to 1.2.2 (#27405) Bumps [tree-kill](https://github.com/pkrumins/node-tree-kill) from 1.2.1 to 1.2.2. - [Release notes](https://github.com/pkrumins/node-tree-kill/releases) - [Commits](https://github.com/pkrumins/node-tree-kill/compare/v1.2.1...v1.2.2) Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com> * Bump handlebars from 4.4.3 to 4.7.6 (#27416) Bumps [handlebars](https://github.com/wycats/handlebars.js) from 4.4.3 to 4.7.6. - [Release notes](https://github.com/wycats/handlebars.js/releases) - [Changelog](https://github.com/handlebars-lang/handlebars.js/blob/master/release-notes.md) - [Commits](https://github.com/wycats/handlebars.js/compare/v4.4.3...v4.7.6) Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com> * Build(deps): Bump http-proxy from 1.18.0 to 1.18.1 (#27507) Bumps [http-proxy](https://github.com/http-party/node-http-proxy) from 1.18.0 to 1.18.1. - [Release notes](https://github.com/http-party/node-http-proxy/releases) - [Changelog](https://github.com/http-party/node-http-proxy/blob/master/CHANGELOG.md) - [Commits](https://github.com/http-party/node-http-proxy/compare/1.18.0...1.18.1) Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com> * Automation: Add backport github action (#28318) * BackendSrv: Fixes queue countdown when unsubscribe is before response (#28323) * GraphNG: Use AxisSide enum (#28320) * IssueTriage: Needs more info automation and messages (#28137) * IssueTriage: Needs more info automation and messages * Updated * Updated * Updated wording * SAML: IdP-initiated SSO docs (#28280) * SAML: IdP-initiated SSO docs * Update docs/sources/enterprise/saml.md Co-authored-by: Emil Tullstedt <emil.tullstedt@grafana.com> * Apply suggestions from code review Co-authored-by: Emil Tullstedt <emil.tullstedt@grafana.com> Co-authored-by: Emil Tullstedt <emil.tullstedt@grafana.com> * Loki: Run instant query only when doing metric query (#28325) * Run instant query only when doing metric query * Update public/app/plugins/datasource/loki/datasource.ts Co-authored-by: Ivana Huckova <30407135+ivanahuckova@users.noreply.github.com> Co-authored-by: Ivana Huckova <30407135+ivanahuckova@users.noreply.github.com> * Automation: Tweaks to more info message (#28332) * AlertingNG: remove warn/crit from eval prototype (#28334) and misc cleanup * area/grafana/toolkit: update e2e docker image (#28335) * add xvfb to image * comment out toolkit inclusion * add latest tag * update packages for cypress * cleanup script * Update auth-proxy.md (#28339) Fix a minor grammar mistake: 'handling' to 'handle'. * Git: Create .gitattributes for windows line endings (#28340) With this set, Windows users will have text files converted from Windows style line endings (\r\n) to Unix style line endings (\n) when they’re added to the repository. https://www.edwardthomson.com/blog/git_for_windows_line_endings.html * Docs: Add docs for valuepicker (#28327) * Templating: Replace all '$tag' in tag values query (#28343) * Docs: Add missing records from grafana-ui 7.2.1 CHANGELOG (#28302) * Dashboard links: Places drop down list so it's always visible (#28330) * calculating whether to place the list on the right or left edge of the parent * change naming and add import of createRef * Automation: Update backport github action trigger (#28352) It seems like GitHub has solved the problem of running github actions on PRs from forks with access to secrets. https://github.blog/2020-08-03-github-actions-improvements-for-fork-and-pull-request-workflows/#improvements-for-public-repository-forks If I change the event that triggers it to pull_request_target the action is run in the context of the base instead of the merged PR branch * ColorSchemes: Adds more color schemes and text colors that depend on the background (#28305) * Adding more color modes and text colors that depend on the background color * Updates * Updated * Another big value fix * Fixing unit tests * Updated * Updated test * Update * Updated * Updated * Updated * Updated * Added new demo dashboard * Updated * updated * Updated * Updateed * added beta notice * Fixed e2e test * Fix typos Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com> * revert pseduo code * apply feedback * remove HTTP for now * fix backend test * change to datasource * clear input for streams * fix docs? * consistent measure vs measurements * better jsdocs * fix a few jsdoc errors * fix comment style * Remove commented out code Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com> * Clean up code Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com> * Clean up code Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com> * Clean up code Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com> * Clean up code Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com> * Clean up code Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com> * Clean up code Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com> * Clean up code Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com> * Update pkg/models/live.go Co-authored-by: Arve Knudsen <arve.knudsen@gmail.com> * Fix build Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com> * set the stringField Co-authored-by: Torkel Ödegaard <torkel@grafana.org> Co-authored-by: Ivana Huckova <30407135+ivanahuckova@users.noreply.github.com> Co-authored-by: ozhuang <ozhuang.95@gmail.com> Co-authored-by: Arve Knudsen <arve.knudsen@gmail.com> Co-authored-by: Amos Law <ahlaw.dev@gmail.com> Co-authored-by: Alex Khomenko <Clarity-89@users.noreply.github.com> Co-authored-by: Will Browne <wbrowne@users.noreply.github.com> Co-authored-by: Hugo Häggmark <hugo.haggmark@grafana.com> Co-authored-by: The Rock Guy <fabian.bracco@gvcgroup.com.au> Co-authored-by: Sofia Papagiannaki <papagian@users.noreply.github.com> Co-authored-by: Emil Tullstedt <emil.tullstedt@grafana.com> Co-authored-by: Carl Bergquist <carl@grafana.com> Co-authored-by: Jack Westbrook <jack.westbrook@gmail.com> Co-authored-by: Dominik Prokop <dominik.prokop@grafana.com> Co-authored-by: Elliot Pryde <elliot.pryde@elliotpryde.com> Co-authored-by: Zoltán Bedi <zoltan.bedi@gmail.com> Co-authored-by: Andrej Ocenas <mr.ocenas@gmail.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com> Co-authored-by: Alexander Zobnin <alexanderzobnin@gmail.com> Co-authored-by: Kyle Brandt <kyle@grafana.com> Co-authored-by: Brian Gann <briangann@users.noreply.github.com> Co-authored-by: J-F-Far <joel.f.farthing@gmail.com> Co-authored-by: acoder77 <73009264+acoder77@users.noreply.github.com> Co-authored-by: Peter Holmberg <peterholmberg@users.noreply.github.com> Co-authored-by: Krzysztof Dąbrowski <krzysdabro@live.com> Co-authored-by: maknik <mooniczkam@gmail.com>
2020-10-22 00:10:26 -07:00
parent a71eadf379
commit 2aafa39879
35 changed files with 1471 additions and 214 deletions
@@ -1,27 +1,48 @@
 package live

 import (
-	"fmt"
 	"strings"
 )

-// ChannelIdentifier is the channel id split by parts
-type ChannelIdentifier struct {
-	Scope     string // grafana, ds, or plugin
-	Namespace string // feature, id, or name
-	Path      string // path within the channel handler
+// ChannelAddress is the channel ID split by parts.
+type ChannelAddress struct {
+	// Scope is "grafana", "ds", or "plugin".
+	Scope string `json:"scope,omitempty"`
+
+	// Namespace meaning depends on the scope.
+	// * when grafana, namespace is a "feature"
+	// * when ds, namespace is the datasource id
+	// * when plugin, namespace is the plugin name
+	Namespace string `json:"namespace,omitempty"`
+
+	// Within each namespace, the handler can process the path as needed.
+	Path string `json:"path,omitempty"`
 }

-// ParseChannelIdentifier parses the parts from a channel id:
-//   ${scope} / ${namespace} / ${path}
-func ParseChannelIdentifier(id string) (ChannelIdentifier, error) {
+// ParseChannelAddress parses the parts from a channel ID:
+//   ${scope} / ${namespace} / ${path}.
+func ParseChannelAddress(id string) ChannelAddress {
+	addr := ChannelAddress{}
 	parts := strings.SplitN(id, "/", 3)
-	if len(parts) == 3 {
-		return ChannelIdentifier{
-			Scope:     parts[0],
-			Namespace: parts[1],
-			Path:      parts[2],
-		}, nil
+	length := len(parts)
+	if length > 0 {
+		addr.Scope = parts[0]
 	}
-	return ChannelIdentifier{}, fmt.Errorf("Invalid channel id: %s", id)
+	if length > 1 {
+		addr.Namespace = parts[1]
+	}
+	if length > 2 {
+		addr.Path = parts[2]
+	}
+	return addr
+}
+
+// IsValid checks if all parts of the address are valid.
+func (ca *ChannelAddress) IsValid() bool {
+	return ca.Scope != "" && ca.Namespace != "" && ca.Path != ""
+}
+
+// ToChannelID converts this to a single string.
+func (ca *ChannelAddress) ToChannelID() string {
+	return ca.Scope + "/" + ca.Namespace + "/" + ca.Path
 }
@@ -4,27 +4,25 @@ import (
 	"testing"

 	"github.com/google/go-cmp/cmp"
+	"github.com/stretchr/testify/require"
 )

-func TestParseChannelIdentifier(t *testing.T) {
-	ident, err := ParseChannelIdentifier("aaa/bbb/ccc/ddd")
-	if err != nil {
-		t.FailNow()
-	}
+func TestParseChannelAddress_Valid(t *testing.T) {
+	addr := ParseChannelAddress("aaa/bbb/ccc/ddd")
+	require.True(t, addr.IsValid())

-	ex := ChannelIdentifier{
+	ex := ChannelAddress{
 		Scope:     "aaa",
 		Namespace: "bbb",
 		Path:      "ccc/ddd",
 	}

-	if diff := cmp.Diff(ident, ex); diff != "" {
+	if diff := cmp.Diff(addr, ex); diff != "" {
 		t.Fatalf("Result mismatch (-want +got):\n%s", diff)
 	}
-
-	// Check an invalid identifier
-	_, err = ParseChannelIdentifier("aaa/bbb")
-	if err == nil {
-		t.FailNow()
-	}
+}
+
+func TestParseChannelAddress_Invalid(t *testing.T) {
+	addr := ParseChannelAddress("aaa/bbb")
+	require.False(t, addr.IsValid())
 }
@@ -6,27 +6,28 @@ import (
 )

 // BroadcastRunner will simply broadcast all events to `grafana/broadcast/*` channels
-// This makes no assumptions about the shape of the data and will broadcast it to anyone listening
-type BroadcastRunner struct{}
+// This assumes that data is a JSON object
+type BroadcastRunner struct {
+}

 // GetHandlerForPath called on init
-func (g *BroadcastRunner) GetHandlerForPath(path string) (models.ChannelHandler, error) {
-	return g, nil // for now all channels share config
+func (b *BroadcastRunner) GetHandlerForPath(path string) (models.ChannelHandler, error) {
+	return b, nil // for now all channels share config
 }

 // GetChannelOptions called fast and often
-func (g *BroadcastRunner) GetChannelOptions(id string) centrifuge.ChannelOptions {
+func (b *BroadcastRunner) GetChannelOptions(id string) centrifuge.ChannelOptions {
 	return centrifuge.ChannelOptions{}
 }

 // OnSubscribe for now allows anyone to subscribe to any dashboard
-func (g *BroadcastRunner) OnSubscribe(c *centrifuge.Client, e centrifuge.SubscribeEvent) error {
+func (b *BroadcastRunner) OnSubscribe(c *centrifuge.Client, e centrifuge.SubscribeEvent) error {
 	// anyone can subscribe
 	return nil
 }

 // OnPublish called when an event is received from the websocket
-func (g *BroadcastRunner) OnPublish(c *centrifuge.Client, e centrifuge.PublishEvent) ([]byte, error) {
+func (b *BroadcastRunner) OnPublish(c *centrifuge.Client, e centrifuge.PublishEvent) ([]byte, error) {
 	// expect the data to be the right shape?
 	return e.Data, nil
 }
@@ -17,14 +17,7 @@ type dashboardEvent struct {

 // DashboardHandler manages all the `grafana/dashboard/*` channels
 type DashboardHandler struct {
-	publisher models.ChannelPublisher
-}
-
-// CreateDashboardHandler Initialize a dashboard handler
-func CreateDashboardHandler(p models.ChannelPublisher) DashboardHandler {
-	return DashboardHandler{
-		publisher: p,
-	}
+	Publisher models.ChannelPublisher
 }

 // GetHandlerForPath called on init
@@ -58,7 +51,7 @@ func (g *DashboardHandler) publish(event dashboardEvent) error {
 	if err != nil {
 		return err
 	}
-	return g.publisher("grafana/dashboard/"+event.UID, msg)
+	return g.Publisher("grafana/dashboard/"+event.UID, msg)
 }

 // DashboardSaved will broadcast to all connected dashboards
@@ -0,0 +1,41 @@
+package features
+
+import (
+	"github.com/centrifugal/centrifuge"
+	"github.com/grafana/grafana/pkg/infra/log"
+	"github.com/grafana/grafana/pkg/models"
+)
+
+var (
+	logger = log.New("live.features") // scoped to all features?
+)
+
+// MeasurementsRunner will simply broadcast all events to `grafana/broadcast/*` channels.
+// This makes no assumptions about the shape of the data and will broadcast it to anyone listening
+type MeasurementsRunner struct {
+}
+
+// GetHandlerForPath gets the handler for a path.
+// It's called on init.
+func (m *MeasurementsRunner) GetHandlerForPath(path string) (models.ChannelHandler, error) {
+	return m, nil // for now all channels share config
+}
+
+// GetChannelOptions gets channel options.
+// It gets called fast and often.
+func (m *MeasurementsRunner) GetChannelOptions(id string) centrifuge.ChannelOptions {
+	return centrifuge.ChannelOptions{}
+}
+
+// OnSubscribe for now allows anyone to subscribe to any dashboard.
+func (m *MeasurementsRunner) OnSubscribe(c *centrifuge.Client, e centrifuge.SubscribeEvent) error {
+	// anyone can subscribe
+	return nil
+}
+
+// OnPublish is called when an event is received from the websocket.
+func (m *MeasurementsRunner) OnPublish(c *centrifuge.Client, e centrifuge.PublishEvent) ([]byte, error) {
+	// currently generic... but should be stricter
+	// logger.Debug("Measurements runner got event on channel", "channel", e.Channel)
+	return e.Data, nil
+}
@@ -7,48 +7,43 @@ import (
 	"time"

 	"github.com/centrifugal/centrifuge"
-	"github.com/grafana/grafana/pkg/cmd/grafana-cli/logger"
 	"github.com/grafana/grafana/pkg/models"
 )

-// TestdataRunner manages all the `grafana/dashboard/*` channels
-type testdataRunner struct {
+// testDataRunner manages all the `grafana/dashboard/*` channels.
+type testDataRunner struct {
 	publisher   models.ChannelPublisher
 	running     bool
 	speedMillis int
 	dropPercent float64
 	channel     string
+	name        string
 }

-// TestdataSupplier manages all the `grafana/testdata/*` channels
-type TestdataSupplier struct {
-	publisher models.ChannelPublisher
+// TestDataSupplier manages all the `grafana/testdata/*` channels.
+type TestDataSupplier struct {
+	Publisher models.ChannelPublisher
 }

-// CreateTestdataSupplier Initialize a dashboard handler
-func CreateTestdataSupplier(p models.ChannelPublisher) TestdataSupplier {
-	return TestdataSupplier{
-		publisher: p,
-	}
-}
-
-// GetHandlerForPath called on init
-func (g *TestdataSupplier) GetHandlerForPath(path string) (models.ChannelHandler, error) {
+// GetHandlerForPath gets the channel handler for a path.
+// Called on init.
+func (g *TestDataSupplier) GetHandlerForPath(path string) (models.ChannelHandler, error) {
 	channel := "grafana/testdata/" + path

 	if path == "random-2s-stream" {
-		return &testdataRunner{
-			publisher:   g.publisher,
+		return &testDataRunner{
+			publisher:   g.Publisher,
 			running:     false,
 			speedMillis: 2000,
 			dropPercent: 0,
 			channel:     channel,
+			name:        path,
 		}, nil
 	}

 	if path == "random-flakey-stream" {
-		return &testdataRunner{
-			publisher:   g.publisher,
+		return &testDataRunner{
+			publisher:   g.Publisher,
 			running:     false,
 			speedMillis: 400,
 			dropPercent: .6,
@@ -59,13 +54,14 @@ func (g *TestdataSupplier) GetHandlerForPath(path string) (models.ChannelHandler
 	return nil, fmt.Errorf("unknown channel")
 }

-// GetChannelOptions called fast and often
-func (g *testdataRunner) GetChannelOptions(id string) centrifuge.ChannelOptions {
+// GetChannelOptions gets channel options.
+// Called fast and often.
+func (g *testDataRunner) GetChannelOptions(id string) centrifuge.ChannelOptions {
 	return centrifuge.ChannelOptions{}
 }

-// OnSubscribe for now allows anyone to subscribe to any dashboard
-func (g *testdataRunner) OnSubscribe(c *centrifuge.Client, e centrifuge.SubscribeEvent) error {
+// OnSubscribe for now allows anyone to subscribe to any dashboard.
+func (g *testDataRunner) OnSubscribe(c *centrifuge.Client, e centrifuge.SubscribeEvent) error {
 	if !g.running {
 		g.running = true

@@ -77,26 +73,26 @@ func (g *testdataRunner) OnSubscribe(c *centrifuge.Client, e centrifuge.Subscrib
 	return nil
 }

-// OnPublish called when an event is received from the websocket
-func (g *testdataRunner) OnPublish(c *centrifuge.Client, e centrifuge.PublishEvent) ([]byte, error) {
+// OnPublish is called when an event is received from the websocket.
+func (g *testDataRunner) OnPublish(c *centrifuge.Client, e centrifuge.PublishEvent) ([]byte, error) {
 	return nil, fmt.Errorf("can not publish to testdata")
 }

-type randomWalkMessage struct {
-	Time  int64
-	Value float64
-	Min   float64
-	Max   float64
-}
-
-// RunRandomCSV just for an example
-func (g *testdataRunner) runRandomCSV() {
+// runRandomCSV is just for an example.
+func (g *testDataRunner) runRandomCSV() {
 	spread := 50.0

 	walker := rand.Float64() * 100
 	ticker := time.NewTicker(time.Duration(g.speedMillis) * time.Millisecond)

-	line := randomWalkMessage{}
+	measurement := models.Measurement{
+		Name:   g.name,
+		Time:   0,
+		Values: make(map[string]interface{}, 5),
+	}
+	msg := models.MeasurementBatch{
+		Measurements: []models.Measurement{measurement}, // always a single measurement
+	}

 	for t := range ticker.C {
 		if rand.Float64() <= g.dropPercent {
@@ -105,12 +101,12 @@ func (g *testdataRunner) runRandomCSV() {
 		delta := rand.Float64() - 0.5
 		walker += delta

-		line.Time = t.UnixNano() / int64(time.Millisecond)
-		line.Value = walker
-		line.Min = walker - ((rand.Float64() * spread) + 0.01)
-		line.Max = walker + ((rand.Float64() * spread) + 0.01)
+		measurement.Time = t.UnixNano() / int64(time.Millisecond)
+		measurement.Values["value"] = walker
+		measurement.Values["min"] = walker - ((rand.Float64() * spread) + 0.01)
+		measurement.Values["max"] = walker + ((rand.Float64() * spread) + 0.01)

-		bytes, err := json.Marshal(&line)
+		bytes, err := json.Marshal(&msg)
 		if err != nil {
 			logger.Warn("unable to marshal line", "error", err)
 			continue
@@ -118,7 +114,7 @@ func (g *testdataRunner) runRandomCSV() {

 		err = g.publisher(g.channel, bytes)
 		if err != nil {
-			logger.Warn("write", "channel", g.channel, "line", line)
+			logger.Warn("write", "channel", g.channel, "measurement", measurement)
 		}
 	}
 }
@@ -20,7 +20,7 @@ var (

 // CoreGrafanaScope list of core features
 type CoreGrafanaScope struct {
-	Features map[string]models.ChannelHandlerProvider
+	Features map[string]models.ChannelHandlerFactory

 	// The generic service to advertise dashboard changes
 	Dashboards models.DashboardActivityChannel
@@ -47,7 +47,7 @@ func InitializeBroker() (*GrafanaLive, error) {
 		channels:   make(map[string]models.ChannelHandler),
 		channelsMu: sync.RWMutex{},
 		GrafanaScope: CoreGrafanaScope{
-			Features: make(map[string]models.ChannelHandlerProvider),
+			Features: make(map[string]models.ChannelHandlerFactory),
 		},
 	}

@@ -83,13 +83,17 @@ func InitializeBroker() (*GrafanaLive, error) {
 	glive.node = node

 	// Initialize the main features
-	dash := features.CreateDashboardHandler(glive.Publish)
-	tds := features.CreateTestdataSupplier(glive.Publish)
+	dash := &features.DashboardHandler{
+		Publisher: glive.Publish,
+	}

-	glive.GrafanaScope.Dashboards = &dash
-	glive.GrafanaScope.Features["dashboard"] = &dash
-	glive.GrafanaScope.Features["testdata"] = &tds
+	glive.GrafanaScope.Dashboards = dash
+	glive.GrafanaScope.Features["dashboard"] = dash
+	glive.GrafanaScope.Features["testdata"] = &features.TestDataSupplier{
+		Publisher: glive.Publish,
+	}
 	glive.GrafanaScope.Features["broadcast"] = &features.BroadcastRunner{}
+	glive.GrafanaScope.Features["measurements"] = &features.MeasurementsRunner{}

 	// Set ConnectHandler called when client successfully connected to Node. Your code
 	// inside handler must be synchronized since it will be called concurrently from
@@ -232,11 +236,11 @@ func (g *GrafanaLive) GetChannelHandler(channel string) (models.ChannelHandler,
 	}

 	// Parse the identifier ${scope}/${namespace}/${path}
-	id, err := ParseChannelIdentifier(channel)
-	if err != nil {
-		return nil, err
+	addr := ParseChannelAddress(channel)
+	if !addr.IsValid() {
+		return nil, fmt.Errorf("invalid channel: %q", channel)
 	}
-	logger.Info("initChannel", "channel", channel, "id", id)
+	logger.Info("initChannel", "channel", channel, "address", addr)

 	g.channelsMu.Lock()
 	defer g.channelsMu.Unlock()
@@ -245,39 +249,48 @@ func (g *GrafanaLive) GetChannelHandler(channel string) (models.ChannelHandler,
 		return c, nil
 	}

-	c, err = g.initChannel(id)
+	getter, err := g.GetChannelHandlerFactory(addr.Scope, addr.Namespace)
 	if err != nil {
 		return nil, err
 	}
+
+	// First access will initialize
+	c, err = getter.GetHandlerForPath(addr.Path)
+	if err != nil {
+		return nil, err
+	}
+
 	g.channels[channel] = c
 	return c, nil
 }

-func (g *GrafanaLive) initChannel(id ChannelIdentifier) (models.ChannelHandler, error) {
-	if id.Scope == "grafana" {
-		p, ok := g.GrafanaScope.Features[id.Namespace]
+// GetChannelHandlerFactory gets a ChannelHandlerFactory for a namespace.
+// It gives threadsafe access to the channel.
+func (g *GrafanaLive) GetChannelHandlerFactory(scope string, name string) (models.ChannelHandlerFactory, error) {
+	if scope == "grafana" {
+		p, ok := g.GrafanaScope.Features[name]
 		if ok {
-			return p.GetHandlerForPath(id.Path)
+			return p, nil
 		}
-		return nil, fmt.Errorf("Unknown feature: %s", id.Namespace)
+		return nil, fmt.Errorf("unknown feature: %q", name)
 	}

-	if id.Scope == "ds" {
-		return nil, fmt.Errorf("todo... look up datasource: %s", id.Namespace)
+	if scope == "ds" {
+		return nil, fmt.Errorf("todo... look up datasource: %q", name)
 	}

-	if id.Scope == "plugin" {
-		p, ok := plugins.Plugins[id.Namespace]
+	if scope == "plugin" {
+		p, ok := plugins.Plugins[name]
 		if ok {
 			h := &PluginHandler{
 				Plugin: p,
 			}
-			return h.GetHandlerForPath(id.Path)
+			return h, nil
 		}
-		return nil, fmt.Errorf("unknown plugin: %s", id.Namespace)
+		return nil, fmt.Errorf("unknown plugin: %q", name)
 	}

-	return nil, fmt.Errorf("invalid scope: %s", id.Scope)
+	return nil, fmt.Errorf("invalid scope: %q", scope)
 }

 // Publish sends the data to the channel without checking permissions etc