fix: nil meter instance used in exporter (#492)

Fixes #491

exporter/clickhousemetricsexporterv2/exporter.go

@@ -19,6 +19,7 @@ import (
 	semconv "go.opentelemetry.io/collector/semconv/v1.5.0"
 	"go.opentelemetry.io/otel/attribute"
 	metricapi "go.opentelemetry.io/otel/metric"
+	"go.opentelemetry.io/otel/metric/noop"
 	"go.uber.org/zap"
 )
 
@@ -36,6 +37,7 @@ var (
 	timeSeriesSQLTmpl = "INSERT INTO %s.%s (env, temporality, metric_name, description, unit, type, is_monotonic, fingerprint, unix_milli, labels, attrs, scope_attrs, resource_attrs) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)"
 	expHistSQLTmpl    = "INSERT INTO %s.%s (env, temporality, metric_name, fingerprint, unix_milli, count, sum, min, max, sketch) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?)"
 	metadataSQLTmpl   = "INSERT INTO %s.%s (temporality, metric_name, description, unit, type, is_monotonic, attr_name, attr_type, attr_datatype, attr_string_value, first_reported_unix_milli, last_reported_unix_milli) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)"
+	meterScope        = "github.com/SigNoz/signoz-otel-collector/exporter/clickhousemetricsexporterv2"
 )
 
 type clickhouseMetricsExporter struct {
@@ -181,6 +183,7 @@ func defaultOptions() []ExporterOption {
 		WithCache(cache),
 		WithLogger(zap.NewNop()),
 		WithEnableExpHist(false),
+		WithMeter(noop.NewMeterProvider().Meter(meterScope)),
 	}
 }
 

exporter/clickhousemetricsexporterv2/factory.go

@@ -47,6 +47,7 @@ func createMetricsExporter(ctx context.Context, set exporter.Settings,
 		WithConfig(chCfg),
 		WithConn(conn),
 		WithLogger(set.Logger),
+		WithMeter(set.MeterProvider.Meter(meterScope)),
 		WithEnableExpHist(chCfg.EnableExpHist),
 	)
 	if err != nil {