[exporter/loki] remove opencensus usage (#30171)

Fixes #30170

---------

Signed-off-by: Alex Boten <[email protected]>

.chloggen/codeboten_rm-census-loki.yaml

@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: lokiexporter
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: migrate metrics to use OpenTelemetry
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [30170]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []

exporter/lokiexporter/exporter.go

@@ -15,13 +15,14 @@ import (
 
 	"github.com/gogo/protobuf/proto"
 	"github.com/golang/snappy"
-	"go.opencensus.io/stats"
 	"go.opentelemetry.io/collector/component"
 	"go.opentelemetry.io/collector/consumer/consumererror"
 	"go.opentelemetry.io/collector/pdata/plog"
+	"go.opentelemetry.io/otel/metric"
 	"go.uber.org/multierr"
 	"go.uber.org/zap"
 
+	"github.com/open-telemetry/opentelemetry-collector-contrib/exporter/lokiexporter/internal/metadata"
 	"github.com/open-telemetry/opentelemetry-collector-contrib/pkg/translator/loki"
 )
 
@@ -35,15 +36,28 @@ type lokiExporter struct {
 	settings component.TelemetrySettings
 	client   *http.Client
 	wg       sync.WaitGroup
+
+	lokiExporterFailedToSendLogRecordsDueToMissingLabels metric.Int64Counter
 }
 
-func newExporter(config *Config, settings component.TelemetrySettings) *lokiExporter {
+func newExporter(config *Config, settings component.TelemetrySettings) (*lokiExporter, error) {
 	settings.Logger.Info("using the new Loki exporter")
 
+	count, err := metadata.Meter(settings).Int64Counter(
+		"lokiexporter_send_failed_due_to_missing_labels",
+		metric.WithDescription("Number of log records failed to send because labels were missing"),
+		metric.WithUnit("1"),
+	)
+
+	if err != nil {
+		return nil, err
+	}
+
 	return &lokiExporter{
 		config:   config,
 		settings: settings,
-	}
+		lokiExporterFailedToSendLogRecordsDueToMissingLabels: count,
+	}, nil
 }
 
 func (l *lokiExporter) pushLogData(ctx context.Context, ld plog.Logs) error {
@@ -53,7 +67,7 @@ func (l *lokiExporter) pushLogData(ctx context.Context, ld plog.Logs) error {
 	for tenant, request := range requests {
 		err := l.sendPushRequest(ctx, tenant, request, ld)
 		if isErrMissingLabels(err) {
-			stats.Record(ctx, lokiExporterFailedToSendLogRecordsDueToMissingLabels.M(int64(ld.LogRecordCount())))
+			l.lokiExporterFailedToSendLogRecordsDueToMissingLabels.Add(ctx, int64(ld.LogRecordCount()))
 		}
 
 		errs = multierr.Append(errs, err)

exporter/lokiexporter/factory.go

@@ -9,7 +9,6 @@ import (
 	"context"
 	"time"
 
-	"go.opencensus.io/stats/view"
 	"go.opentelemetry.io/collector/component"
 	"go.opentelemetry.io/collector/config/confighttp"
 	"go.opentelemetry.io/collector/config/configopaque"
@@ -22,8 +21,6 @@ import (
 
 // NewFactory creates a factory for the legacy Loki exporter.
 func NewFactory() exporter.Factory {
-	_ = view.Register(metricViews()...)
-
 	return exporter.NewFactory(
 		metadata.Type,
 		createDefaultConfig,
@@ -53,7 +50,11 @@ func createDefaultConfig() component.Config {
 
 func createLogsExporter(ctx context.Context, set exporter.CreateSettings, config component.Config) (exporter.Logs, error) {
 	exporterConfig := config.(*Config)
-	exp := newExporter(exporterConfig, set.TelemetrySettings)
+	exp, err := newExporter(exporterConfig, set.TelemetrySettings)
+
+	if err != nil {
+		return nil, err
+	}
 
 	return exporterhelper.NewLogsExporter(
 		ctx,

exporter/lokiexporter/factory_test.go

@@ -25,7 +25,8 @@ func TestExporter_new(t *testing.T) {
 				Endpoint: validEndpoint,
 			},
 		}
-		exp := newExporter(config, componenttest.NewNopTelemetrySettings())
+		exp, err := newExporter(config, componenttest.NewNopTelemetrySettings())
+		require.NoError(t, err)
 		require.NotNil(t, exp)
 	})
 }
@@ -36,7 +37,8 @@ func TestExporter_startReturnsNillWhenValidConfig(t *testing.T) {
 			Endpoint: validEndpoint,
 		},
 	}
-	exp := newExporter(config, componenttest.NewNopTelemetrySettings())
+	exp, err := newExporter(config, componenttest.NewNopTelemetrySettings())
+	require.NoError(t, err)
 	require.NotNil(t, exp)
 	require.NoError(t, exp.start(context.Background(), componenttest.NewNopHost()))
 }
@@ -50,7 +52,8 @@ func TestExporter_startReturnsErrorWhenInvalidHttpClientSettings(t *testing.T) {
 			},
 		},
 	}
-	exp := newExporter(config, componenttest.NewNopTelemetrySettings())
+	exp, err := newExporter(config, componenttest.NewNopTelemetrySettings())
+	require.NoError(t, err)
 	require.NotNil(t, exp)
 	require.Error(t, exp.start(context.Background(), componenttest.NewNopHost()))
 }
@@ -61,7 +64,8 @@ func TestExporter_stopAlwaysReturnsNil(t *testing.T) {
 			Endpoint: validEndpoint,
 		},
 	}
-	exp := newExporter(config, componenttest.NewNopTelemetrySettings())
+	exp, err := newExporter(config, componenttest.NewNopTelemetrySettings())
+	require.NoError(t, err)
 	require.NotNil(t, exp)
 	require.NoError(t, exp.stop(context.Background()))
 }

exporter/lokiexporter/go.mod

@@ -10,7 +10,6 @@ require (
 	github.com/open-telemetry/opentelemetry-collector-contrib/pkg/translator/loki v0.92.0
 	github.com/prometheus/common v0.46.0
 	github.com/stretchr/testify v1.8.4
-	go.opencensus.io v0.24.0
 	go.opentelemetry.io/collector v0.92.1-0.20240118172122-8131d31601b8
 	go.opentelemetry.io/collector/component v0.92.1-0.20240118172122-8131d31601b8
 	go.opentelemetry.io/collector/config/confighttp v0.92.1-0.20240118172122-8131d31601b8
@@ -64,6 +63,7 @@ require (
 	github.com/prometheus/prometheus v0.48.1 // indirect
 	github.com/prometheus/statsd_exporter v0.22.7 // indirect
 	github.com/rs/cors v1.10.1 // indirect
+	go.opencensus.io v0.24.0 // indirect
 	go.opentelemetry.io/collector/config/configauth v0.92.1-0.20240118172122-8131d31601b8 // indirect
 	go.opentelemetry.io/collector/config/configcompression v0.92.1-0.20240118172122-8131d31601b8 // indirect
 	go.opentelemetry.io/collector/config/configtelemetry v0.92.1-0.20240118172122-8131d31601b8 // indirect