From 35219ad63112442cea4dcea87e4f357990e6873c Mon Sep 17 00:00:00 2001
From: Alex Boten <aboten@lightstep.com>
Date: Fri, 2 Jun 2023 11:33:34 -0700
Subject: [PATCH 01/10] add method to return a prometheus configuration struct

Signed-off-by: Alex Boten <aboten@lightstep.com>
---
 internal/testutil/testutil.go | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/internal/testutil/testutil.go b/internal/testutil/testutil.go
index 8f573b8ba37..f053b1caca2 100644
--- a/internal/testutil/testutil.go
+++ b/internal/testutil/testutil.go
@@ -7,11 +7,13 @@ import (
 	"net"
 	"os/exec"
 	"runtime"
+	"strconv"
 	"strings"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	"go.opentelemetry.io/collector/service/telemetry"
 )
 
 type portpair struct {
@@ -54,6 +56,22 @@ func GetAvailableLocalAddress(t testing.TB) string {
 	return endpoint
 }
 
+func GetAvailableLocalAddressPrometheus(t testing.TB) telemetry.Prometheus {
+	address := GetAvailableLocalAddress(t)
+	host, port, err := net.SplitHostPort(address)
+	if err != nil {
+		return telemetry.Prometheus{}
+	}
+	portInt, err := strconv.Atoi(port)
+	if err != nil {
+		return telemetry.Prometheus{}
+	}
+	return telemetry.Prometheus{
+		Host: &host,
+		Port: &portInt,
+	}
+}
+
 func findAvailableAddress(t testing.TB) string {
 	ln, err := net.Listen("tcp", "localhost:0")
 	require.NoError(t, err, "Failed to get a free local port")

From ef13f4e9e834900d8969dd7488312ba817398c65 Mon Sep 17 00:00:00 2001
From: Alex Boten <aboten@lightstep.com>
Date: Fri, 2 Jun 2023 12:35:34 -0700
Subject: [PATCH 02/10] adding test for extendedConfig w/ metric readers

Signed-off-by: Alex Boten <aboten@lightstep.com>
---
 .chloggen/codeboten_may-29-otlp-export.yaml   |  21 +++
 exporter/otlpexporter/go.mod                  |   1 +
 exporter/otlpexporter/go.sum                  |   1 +
 exporter/otlphttpexporter/go.mod              |   1 +
 exporter/otlphttpexporter/go.sum              |   1 +
 go.mod                                        |   2 +-
 internal/testutil/testutil.go                 |   1 +
 service/internal/proctelemetry/config.go      |  87 +++++++++++++
 service/internal/proctelemetry/config_test.go |  69 ++++++++++
 service/telemetry.go                          | 120 ++++++++++--------
 service/telemetry/config.go                   |  43 ++++++-
 service/telemetry/config_test.go              |  71 +++++++++++
 service/telemetry_test.go                     |  77 +++++++++--
 13 files changed, 426 insertions(+), 69 deletions(-)
 create mode 100755 .chloggen/codeboten_may-29-otlp-export.yaml

diff --git a/.chloggen/codeboten_may-29-otlp-export.yaml b/.chloggen/codeboten_may-29-otlp-export.yaml
new file mode 100755
index 00000000000..a22bbae5bd7
--- /dev/null
+++ b/.chloggen/codeboten_may-29-otlp-export.yaml
@@ -0,0 +1,21 @@
+# 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. otlpreceiver)
+component: service
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: "add ability to configure prometheus export via `metric_readers`"
+
+# One or more tracking issues or pull requests related to the change
+issues: [7641]
+
+# (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: |
+  This enables end users to configure additional prometheus exporters for the collector's telemetry
+  via the `metric_readers` configuration option. Configuring prometheus through the existing method
+  of setting the service::metrics::address will continue to work, and only log a warning for users
+  who have enabled the `telemetry.useOtelWithSDKConfigurationForInternalTelemetry` feature gate.
+
diff --git a/exporter/otlpexporter/go.mod b/exporter/otlpexporter/go.mod
index 2daadd8f71b..5fb69d00177 100644
--- a/exporter/otlpexporter/go.mod
+++ b/exporter/otlpexporter/go.mod
@@ -53,6 +53,7 @@ require (
 	go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.42.1-0.20230612162650-64be7e574a17 // indirect
 	go.opentelemetry.io/otel v1.16.0 // indirect
 	go.opentelemetry.io/otel/metric v1.16.0 // indirect
+	go.opentelemetry.io/otel/sdk v1.16.0 // indirect
 	go.opentelemetry.io/otel/trace v1.16.0 // indirect
 	go.uber.org/atomic v1.10.0 // indirect
 	go.uber.org/multierr v1.11.0 // indirect
diff --git a/exporter/otlpexporter/go.sum b/exporter/otlpexporter/go.sum
index 837ce0c528d..497d1ad304c 100644
--- a/exporter/otlpexporter/go.sum
+++ b/exporter/otlpexporter/go.sum
@@ -296,6 +296,7 @@ go.opentelemetry.io/otel/exporters/prometheus v0.39.0 h1:whAaiHxOatgtKd+w0dOi//1
 go.opentelemetry.io/otel/metric v1.16.0 h1:RbrpwVG1Hfv85LgnZ7+txXioPDoh6EdbZHo26Q3hqOo=
 go.opentelemetry.io/otel/metric v1.16.0/go.mod h1:QE47cpOmkwipPiefDwo2wDzwJrlfxxNYodqc4xnGCo4=
 go.opentelemetry.io/otel/sdk v1.16.0 h1:Z1Ok1YsijYL0CSJpHt4cS3wDDh7p572grzNrBMiMWgE=
+go.opentelemetry.io/otel/sdk v1.16.0/go.mod h1:tMsIuKXuuIWPBAOrH+eHtvhTL+SntFtXF9QD68aP6p4=
 go.opentelemetry.io/otel/sdk/metric v0.39.0 h1:Kun8i1eYf48kHH83RucG93ffz0zGV1sh46FAScOTuDI=
 go.opentelemetry.io/otel/trace v1.16.0 h1:8JRpaObFoW0pxuVPapkgH8UhHQj+bJW8jJsCZEu5MQs=
 go.opentelemetry.io/otel/trace v1.16.0/go.mod h1:Yt9vYq1SdNz3xdjZZK7wcXv1qv2pwLkqr2QVwea0ef0=
diff --git a/exporter/otlphttpexporter/go.mod b/exporter/otlphttpexporter/go.mod
index 40b2d70eb78..6dc715efca5 100644
--- a/exporter/otlphttpexporter/go.mod
+++ b/exporter/otlphttpexporter/go.mod
@@ -58,6 +58,7 @@ require (
 	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.42.0 // indirect
 	go.opentelemetry.io/otel v1.16.0 // indirect
 	go.opentelemetry.io/otel/metric v1.16.0 // indirect
+	go.opentelemetry.io/otel/sdk v1.16.0 // indirect
 	go.opentelemetry.io/otel/trace v1.16.0 // indirect
 	go.uber.org/atomic v1.10.0 // indirect
 	go.uber.org/multierr v1.11.0 // indirect
diff --git a/exporter/otlphttpexporter/go.sum b/exporter/otlphttpexporter/go.sum
index cc2949fa25b..d2d4c81e0e2 100644
--- a/exporter/otlphttpexporter/go.sum
+++ b/exporter/otlphttpexporter/go.sum
@@ -975,6 +975,7 @@ go.opentelemetry.io/otel/exporters/prometheus v0.39.0 h1:whAaiHxOatgtKd+w0dOi//1
 go.opentelemetry.io/otel/metric v1.16.0 h1:RbrpwVG1Hfv85LgnZ7+txXioPDoh6EdbZHo26Q3hqOo=
 go.opentelemetry.io/otel/metric v1.16.0/go.mod h1:QE47cpOmkwipPiefDwo2wDzwJrlfxxNYodqc4xnGCo4=
 go.opentelemetry.io/otel/sdk v1.16.0 h1:Z1Ok1YsijYL0CSJpHt4cS3wDDh7p572grzNrBMiMWgE=
+go.opentelemetry.io/otel/sdk v1.16.0/go.mod h1:tMsIuKXuuIWPBAOrH+eHtvhTL+SntFtXF9QD68aP6p4=
 go.opentelemetry.io/otel/sdk/metric v0.39.0 h1:Kun8i1eYf48kHH83RucG93ffz0zGV1sh46FAScOTuDI=
 go.opentelemetry.io/otel/trace v1.16.0 h1:8JRpaObFoW0pxuVPapkgH8UhHQj+bJW8jJsCZEu5MQs=
 go.opentelemetry.io/otel/trace v1.16.0/go.mod h1:Yt9vYq1SdNz3xdjZZK7wcXv1qv2pwLkqr2QVwea0ef0=
diff --git a/go.mod b/go.mod
index aa4d1a37151..a58580db4bb 100644
--- a/go.mod
+++ b/go.mod
@@ -5,6 +5,7 @@ go 1.19
 require (
 	contrib.go.opencensus.io/exporter/prometheus v0.4.2
 	github.com/google/uuid v1.3.0
+	github.com/mitchellh/mapstructure v1.5.1-0.20220423185008-bf980b35cac4
 	github.com/prometheus/client_golang v1.16.0
 	github.com/prometheus/client_model v0.4.0
 	github.com/prometheus/common v0.44.0
@@ -61,7 +62,6 @@ require (
 	github.com/lufia/plan9stats v0.0.0-20211012122336-39d0f177ccd0 // indirect
 	github.com/matttproud/golang_protobuf_extensions v1.0.4 // indirect
 	github.com/mitchellh/copystructure v1.2.0 // indirect
-	github.com/mitchellh/mapstructure v1.5.1-0.20220423185008-bf980b35cac4 // indirect
 	github.com/mitchellh/reflectwalk v1.0.2 // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect
diff --git a/internal/testutil/testutil.go b/internal/testutil/testutil.go
index f053b1caca2..4bb1a698374 100644
--- a/internal/testutil/testutil.go
+++ b/internal/testutil/testutil.go
@@ -13,6 +13,7 @@ import (
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+
 	"go.opentelemetry.io/collector/service/telemetry"
 )
 
diff --git a/service/internal/proctelemetry/config.go b/service/internal/proctelemetry/config.go
index f3467d78475..4f7b5f79a4f 100644
--- a/service/internal/proctelemetry/config.go
+++ b/service/internal/proctelemetry/config.go
@@ -4,7 +4,17 @@
 package proctelemetry // import "go.opentelemetry.io/collector/service/internal/proctelemetry"
 
 import (
+	"context"
+	"errors"
+	"fmt"
+	"net/http"
+	"strings"
+
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/bridge/opencensus"
+	otelprom "go.opentelemetry.io/otel/exporters/prometheus"
 	"go.opentelemetry.io/otel/sdk/instrumentation"
 	sdkmetric "go.opentelemetry.io/otel/sdk/metric"
 	"go.opentelemetry.io/otel/sdk/metric/aggregation"
@@ -12,6 +22,7 @@ import (
 
 	"go.opentelemetry.io/collector/obsreport"
 	semconv "go.opentelemetry.io/collector/semconv/v1.18.0"
+	"go.opentelemetry.io/collector/service/telemetry"
 )
 
 const (
@@ -21,6 +32,12 @@ const (
 
 	// http Instrumentation Name
 	HTTPInstrumentation = "go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
+
+	// supported metric readers
+	pullMetricReader = "pull"
+
+	// supported exporters
+	prometheueExporter = "prometheus"
 )
 
 var (
@@ -38,6 +55,20 @@ var (
 	}
 )
 
+func InitMetricReader(ctx context.Context, name string, reader any, asyncErrorChannel chan error) (sdkmetric.Reader, *http.Server, error) {
+	readerType := strings.Split(name, "/")[0]
+	switch readerType {
+	case pullMetricReader:
+		r, ok := reader.(telemetry.PullMetricReader)
+		if !ok {
+			return nil, nil, fmt.Errorf("invalid metric reader configuration: %v", reader)
+		}
+		return initExporter(ctx, r.Exporter, asyncErrorChannel)
+	default:
+		return nil, nil, fmt.Errorf("unsupported metric reader type: %s", readerType)
+	}
+}
+
 func InitOpenTelemetry(res *resource.Resource, options []sdkmetric.Option, disableHighCardinality bool) (*sdkmetric.MeterProvider, error) {
 	opts := []sdkmetric.Option{
 		sdkmetric.WithResource(res),
@@ -50,6 +81,21 @@ func InitOpenTelemetry(res *resource.Resource, options []sdkmetric.Option, disab
 	), nil
 }
 
+func InitPrometheusServer(registry *prometheus.Registry, address string, asyncErrorChannel chan error) *http.Server {
+	mux := http.NewServeMux()
+	mux.Handle("/metrics", promhttp.HandlerFor(registry, promhttp.HandlerOpts{}))
+	server := &http.Server{
+		Addr:    address,
+		Handler: mux,
+	}
+	go func() {
+		if serveErr := server.ListenAndServe(); serveErr != nil && !errors.Is(serveErr, http.ErrServerClosed) {
+			asyncErrorChannel <- serveErr
+		}
+	}()
+	return server
+}
+
 func batchViews(disableHighCardinality bool) []sdkmetric.View {
 	views := []sdkmetric.View{
 		sdkmetric.NewView(
@@ -92,3 +138,44 @@ func cardinalityFilter(kvs ...attribute.KeyValue) attribute.Filter {
 		return !filter.HasValue(kv.Key)
 	}
 }
+
+func initPrometheusExporter(prometheusConfig telemetry.Prometheus, asyncErrorChannel chan error) (sdkmetric.Reader, *http.Server, error) {
+	promRegistry := prometheus.NewRegistry()
+	if prometheusConfig.Host == nil {
+		return nil, nil, fmt.Errorf("host must be specified")
+	}
+	if prometheusConfig.Port == nil {
+		return nil, nil, fmt.Errorf("port must be specified")
+	}
+	wrappedRegisterer := prometheus.WrapRegistererWithPrefix("otelcol_", promRegistry)
+	// We can remove `otelprom.WithoutUnits()` when the otel-go start exposing prometheus metrics using the OpenMetrics format
+	// which includes metric units that prometheusreceiver uses to trim unit's suffixes from metric names.
+	// https://github.com/open-telemetry/opentelemetry-go/issues/3468
+	exporter, err := otelprom.New(
+		otelprom.WithRegisterer(wrappedRegisterer),
+		otelprom.WithoutUnits(),
+		// Disabled for the moment until this becomes stable, and we are ready to break backwards compatibility.
+		otelprom.WithoutScopeInfo())
+	if err != nil {
+		return nil, nil, fmt.Errorf("error creating otel prometheus exporter: %w", err)
+	}
+
+	exporter.RegisterProducer(opencensus.NewMetricProducer())
+	return exporter, InitPrometheusServer(promRegistry, fmt.Sprintf("%s:%d", *prometheusConfig.Host, *prometheusConfig.Port), asyncErrorChannel), nil
+}
+
+func initExporter(_ context.Context, exporters telemetry.MetricExporter, asyncErrorChannel chan error) (sdkmetric.Reader, *http.Server, error) {
+	for exporterType, exporter := range exporters {
+		switch exporterType {
+		case prometheueExporter:
+			e, ok := exporter.(telemetry.Prometheus)
+			if !ok {
+				return nil, nil, fmt.Errorf("prometheus exporter invalid: %v", exporter)
+			}
+			return initPrometheusExporter(e, asyncErrorChannel)
+		default:
+			return nil, nil, fmt.Errorf("unsupported metric exporter type: %s", exporterType)
+		}
+	}
+	return nil, nil, fmt.Errorf("no valid exporter: %v", exporters)
+}
diff --git a/service/internal/proctelemetry/config_test.go b/service/internal/proctelemetry/config_test.go
index 01e368b2898..49edd31474e 100644
--- a/service/internal/proctelemetry/config_test.go
+++ b/service/internal/proctelemetry/config_test.go
@@ -2,3 +2,72 @@
 // SPDX-License-Identifier: Apache-2.0
 
 package proctelemetry
+
+import (
+	"context"
+	"errors"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"go.opentelemetry.io/collector/service/telemetry"
+)
+
+func strPtr(s string) *string {
+	return &s
+}
+
+func intPtr(i int) *int {
+	return &i
+}
+
+func TestMetricReader(t *testing.T) {
+	testCases := []struct {
+		name   string
+		reader any
+		args   any
+		err    error
+	}{
+		{
+			name: "noreader",
+			err:  errors.New("unsupported metric reader type: noreader"),
+		},
+		{
+			name: "pull/prometheus-invalid-config-no-host",
+			reader: telemetry.PullMetricReader{
+				Exporter: telemetry.MetricExporter{
+					"prometheus": telemetry.Prometheus{},
+				},
+			},
+			err: errors.New("host must be specified"),
+		},
+		{
+			name: "pull/prometheus-invalid-config-no-port",
+			reader: telemetry.PullMetricReader{
+				Exporter: telemetry.MetricExporter{
+					"prometheus": telemetry.Prometheus{
+						Host: strPtr("locahost"),
+					},
+				},
+			},
+			err: errors.New("port must be specified"),
+		},
+		{
+			name: "pull/prometheus-invalid-config-no-port",
+			reader: telemetry.PullMetricReader{
+				Exporter: telemetry.MetricExporter{
+					"prometheus": telemetry.Prometheus{
+						Host: strPtr("locahost"),
+						Port: intPtr(8080),
+					},
+				},
+			},
+		},
+	}
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			_, _, err := InitMetricReader(context.Background(), tc.name, tc.reader, make(chan error))
+			assert.Equal(t, tc.err, err)
+		})
+	}
+}
diff --git a/service/telemetry.go b/service/telemetry.go
index 1cb8b232ad1..a1e8d337e51 100644
--- a/service/telemetry.go
+++ b/service/telemetry.go
@@ -4,22 +4,21 @@
 package service // import "go.opentelemetry.io/collector/service"
 
 import (
+	"context"
 	"errors"
-	"fmt"
+	"net"
 	"net/http"
+	"strconv"
 	"strings"
 	"unicode"
 
 	ocprom "contrib.go.opencensus.io/exporter/prometheus"
 	"github.com/prometheus/client_golang/prometheus"
-	"github.com/prometheus/client_golang/prometheus/promhttp"
 	ocmetric "go.opencensus.io/metric"
 	"go.opencensus.io/metric/metricproducer"
 	"go.opencensus.io/stats/view"
 	"go.opentelemetry.io/contrib/propagators/b3"
 	"go.opentelemetry.io/otel"
-	"go.opentelemetry.io/otel/bridge/opencensus"
-	otelprom "go.opentelemetry.io/otel/exporters/prometheus"
 	"go.opentelemetry.io/otel/metric"
 	"go.opentelemetry.io/otel/metric/noop"
 	"go.opentelemetry.io/otel/propagation"
@@ -69,7 +68,7 @@ func newColTelemetry(useOtel bool, disableHighCardinality bool, extendedConfig b
 }
 
 func (tel *telemetryInitializer) init(res *resource.Resource, settings component.TelemetrySettings, cfg telemetry.Config, asyncErrorChannel chan error) error {
-	if cfg.Metrics.Level == configtelemetry.LevelNone || cfg.Metrics.Address == "" {
+	if cfg.Metrics.Level == configtelemetry.LevelNone || (cfg.Metrics.Address == "" && len(cfg.Metrics.Readers) == 0) {
 		settings.Logger.Info(
 			"Skipping telemetry setup.",
 			zap.String(zapKeyTelemetryAddress, cfg.Metrics.Address),
@@ -86,44 +85,73 @@ func (tel *telemetryInitializer) init(res *resource.Resource, settings component
 		return err
 	}
 
-	return tel.initPrometheus(res, settings.Logger, cfg.Metrics.Address, cfg.Metrics.Level, asyncErrorChannel)
+	return tel.initMetrics(res, settings.Logger, cfg, asyncErrorChannel)
 }
 
-func (tel *telemetryInitializer) initPrometheus(res *resource.Resource, logger *zap.Logger, address string, level configtelemetry.Level, asyncErrorChannel chan error) error {
-	promRegistry := prometheus.NewRegistry()
-	if tel.useOtel {
-		if err := tel.initOpenTelemetry(res, promRegistry); err != nil {
+func (tel *telemetryInitializer) initMetrics(res *resource.Resource, logger *zap.Logger, cfg telemetry.Config, asyncErrorChannel chan error) error {
+	// Initialize the ocRegistry, still used by the process metrics.
+	tel.ocRegistry = ocmetric.NewRegistry()
+	if !tel.useOtel && !tel.extendedConfig {
+		return tel.initOpenCensus(res, logger, cfg.Metrics.Address, cfg.Metrics.Level, asyncErrorChannel)
+	}
+
+	if len(cfg.Metrics.Address) != 0 {
+		if tel.extendedConfig {
+			logger.Warn("service.telemetry.metrics.address is being deprecated in favor of service.telemetry.metrics.metric_readers")
+		}
+		host, port, err := net.SplitHostPort(cfg.Metrics.Address)
+		if err != nil {
 			return err
 		}
-	} else {
-		if err := tel.initOpenCensus(level, res, promRegistry); err != nil {
+		portInt, err := strconv.Atoi(port)
+		if err != nil {
 			return err
 		}
+		if cfg.Metrics.Readers == nil {
+			cfg.Metrics.Readers = telemetry.MeterProviderJsonMetricReaders{}
+		}
+		cfg.Metrics.Readers["pull/serviceaddress"] = telemetry.PullMetricReader{
+			Exporter: telemetry.MetricExporter{
+				"prometheus": telemetry.Prometheus{
+					Host: &host,
+					Port: &portInt,
+				},
+			},
+		}
 	}
 
-	logger.Info(
-		"Serving Prometheus metrics",
-		zap.String(zapKeyTelemetryAddress, address),
-		zap.String(zapKeyTelemetryLevel, level.String()),
-	)
+	metricproducer.GlobalManager().AddProducer(tel.ocRegistry)
+	opts := []sdkmetric.Option{}
+	for name, reader := range cfg.Metrics.Readers {
+		// @codeboten: server returned here only happens when a pull based metric
+		// reader is configured, this could be refactored to pass in a
+		// func to add the server to the list of servers. another thing that would
+		// be nice is not to have to pass down the asyncErrorChannel
+		r, server, err := proctelemetry.InitMetricReader(context.Background(), name, reader, asyncErrorChannel)
+		if err != nil {
+			return err
+		}
+		if server != nil {
+			tel.servers = append(tel.servers, server)
+			logger.Info(
+				"Serving metrics",
+				zap.String(zapKeyTelemetryAddress, server.Addr),
+				zap.String(zapKeyTelemetryLevel, cfg.Metrics.Level.String()),
+			)
+		}
+		opts = append(opts, sdkmetric.WithReader(r))
+	}
 
-	mux := http.NewServeMux()
-	mux.Handle("/metrics", promhttp.HandlerFor(promRegistry, promhttp.HandlerOpts{}))
-	server := &http.Server{
-		Addr:    address,
-		Handler: mux,
+	mp, err := proctelemetry.InitOpenTelemetry(res, opts, tel.disableHighCardinality)
+	if err != nil {
+		return err
 	}
-	tel.servers = append(tel.servers, server)
-	go func() {
-		if serveErr := server.ListenAndServe(); serveErr != nil && !errors.Is(serveErr, http.ErrServerClosed) {
-			asyncErrorChannel <- serveErr
-		}
-	}()
+	tel.mp = mp
 	return nil
 }
 
-func (tel *telemetryInitializer) initOpenCensus(level configtelemetry.Level, res *resource.Resource, promRegistry *prometheus.Registry) error {
-	tel.ocRegistry = ocmetric.NewRegistry()
+func (tel *telemetryInitializer) initOpenCensus(res *resource.Resource, logger *zap.Logger, address string, level configtelemetry.Level, asyncErrorChannel chan error) error {
+	promRegistry := prometheus.NewRegistry()
 	metricproducer.GlobalManager().AddProducer(tel.ocRegistry)
 
 	tel.views = obsreportconfig.AllViews(level)
@@ -148,33 +176,13 @@ func (tel *telemetryInitializer) initOpenCensus(level configtelemetry.Level, res
 	}
 
 	view.RegisterExporter(pe)
-	return nil
-}
-
-func (tel *telemetryInitializer) initOpenTelemetry(res *resource.Resource, promRegistry *prometheus.Registry) error {
-	// Initialize the ocRegistry, still used by the process metrics.
-	tel.ocRegistry = ocmetric.NewRegistry()
-	metricproducer.GlobalManager().AddProducer(tel.ocRegistry)
-
-	wrappedRegisterer := prometheus.WrapRegistererWithPrefix("otelcol_", promRegistry)
-	// We can remove `otelprom.WithoutUnits()` when the otel-go start exposing prometheus metrics using the OpenMetrics format
-	// which includes metric units that prometheusreceiver uses to trim unit's suffixes from metric names.
-	// https://github.com/open-telemetry/opentelemetry-go/issues/3468
-	exporter, err := otelprom.New(
-		otelprom.WithRegisterer(wrappedRegisterer),
-		otelprom.WithoutUnits(),
-		// Disabled for the moment until this becomes stable, and we are ready to break backwards compatibility.
-		otelprom.WithoutScopeInfo())
-	if err != nil {
-		return fmt.Errorf("error creating otel prometheus exporter: %w", err)
-	}
 
-	exporter.RegisterProducer(opencensus.NewMetricProducer())
-	mp, err := proctelemetry.InitOpenTelemetry(res, []sdkmetric.Option{sdkmetric.WithReader(exporter)}, tel.disableHighCardinality)
-	if err != nil {
-		return err
-	}
-	tel.mp = mp
+	logger.Info(
+		"Serving Prometheus metrics",
+		zap.String(zapKeyTelemetryAddress, address),
+		zap.String(zapKeyTelemetryLevel, level.String()),
+	)
+	tel.servers = append(tel.servers, proctelemetry.InitPrometheusServer(promRegistry, address, asyncErrorChannel))
 	return nil
 }
 
diff --git a/service/telemetry/config.go b/service/telemetry/config.go
index 797f53bfd2d..f45bd3040f2 100644
--- a/service/telemetry/config.go
+++ b/service/telemetry/config.go
@@ -5,10 +5,13 @@ package telemetry // import "go.opentelemetry.io/collector/service/telemetry"
 
 import (
 	"fmt"
+	"strings"
 
+	"github.com/mitchellh/mapstructure"
 	"go.uber.org/zap/zapcore"
 
 	"go.opentelemetry.io/collector/config/configtelemetry"
+	"go.opentelemetry.io/collector/confmap"
 )
 
 // Config defines the configurable settings for service telemetry.
@@ -108,7 +111,7 @@ type MetricsConfig struct {
 
 	// Readers allow configuration of metric readers to emit metrics to
 	// any number of supported backends.
-	Readers []MetricReader `mapstructure:"metric_readers"`
+	Readers MeterProviderJsonMetricReaders `mapstructure:"metric_readers"`
 }
 
 // TracesConfig exposes the common Telemetry configuration for collector's internal spans.
@@ -124,9 +127,45 @@ type TracesConfig struct {
 func (c *Config) Validate() error {
 
 	// Check when service telemetry metric level is not none, the metrics address should not be empty
-	if c.Metrics.Level != configtelemetry.LevelNone && c.Metrics.Address == "" {
+	if c.Metrics.Level != configtelemetry.LevelNone && c.Metrics.Address == "" && len(c.Metrics.Readers) == 0 {
 		return fmt.Errorf("collector telemetry metric address should exist when metric level is not none")
 	}
 
 	return nil
 }
+
+func (mrs *MeterProviderJsonMetricReaders) Unmarshal(conf *confmap.Conf) error {
+	if err := conf.Unmarshal(mrs); err != nil {
+		return err
+	}
+	if *mrs == nil {
+		*mrs = make(MeterProviderJsonMetricReaders)
+	}
+	for key, reader := range *mrs {
+		readerType := strings.Split(key, "/")[0]
+		switch readerType {
+		case "pull":
+			var r PullMetricReader
+			if err := mapstructure.Decode(reader, &r); err != nil {
+				return fmt.Errorf("invalid pull metric reader configuration: %w", err)
+			}
+			(*mrs)[key] = r
+
+			for key, exporter := range r.Exporter {
+				switch key {
+				case "prometheus":
+					var promExporter Prometheus
+					if err := mapstructure.Decode(exporter, &promExporter); err != nil {
+						return fmt.Errorf("invalid exporter configuration: %w", err)
+					}
+					r.Exporter[key] = promExporter
+				default:
+					return fmt.Errorf("unsupported metric exporter type: %s", key)
+				}
+			}
+		default:
+			return fmt.Errorf("unsupported metric reader type: %s", readerType)
+		}
+	}
+	return nil
+}
diff --git a/service/telemetry/config_test.go b/service/telemetry/config_test.go
index aa7502188dc..d07e2014b83 100644
--- a/service/telemetry/config_test.go
+++ b/service/telemetry/config_test.go
@@ -9,6 +9,7 @@ import (
 	"github.com/stretchr/testify/assert"
 
 	"go.opentelemetry.io/collector/config/configtelemetry"
+	"go.opentelemetry.io/collector/confmap"
 )
 
 func TestLoadConfig(t *testing.T) {
@@ -37,6 +38,18 @@ func TestLoadConfig(t *testing.T) {
 			},
 			success: false,
 		},
+		{
+			name: "valid metric telemetry with metric readers",
+			cfg: &Config{
+				Metrics: MetricsConfig{
+					Level: configtelemetry.LevelBasic,
+					Readers: MeterProviderJsonMetricReaders{
+						"pull/prometheus": PullMetricReader{},
+					},
+				},
+			},
+			success: true,
+		},
 	}
 
 	for _, tt := range tests {
@@ -50,3 +63,61 @@ func TestLoadConfig(t *testing.T) {
 		})
 	}
 }
+
+func TestUnmarshalMetricReaders(t *testing.T) {
+	tests := []struct {
+		name string
+		cfg  *confmap.Conf
+		err  string
+	}{
+		{
+			name: "invalid config",
+			cfg:  confmap.NewFromStringMap(map[string]any{"invalid": "invalid"}),
+			err:  "unsupported metric reader type: invalid",
+		},
+		{
+			name: "valid reader type, invalid config",
+			cfg:  confmap.NewFromStringMap(map[string]any{"pull": "garbage"}),
+			err:  "invalid pull metric reader configuration: '' expected a map, got 'string'",
+		},
+		{
+			name: "valid pull reader type, no exporter",
+			cfg:  confmap.NewFromStringMap(map[string]any{"pull": PullMetricReader{}}),
+		},
+		{
+			name: "valid pull reader type, invalid exporter",
+			cfg: confmap.NewFromStringMap(map[string]any{"pull": PullMetricReader{
+				Exporter: MetricExporter{
+					"invalid": "invalid",
+				},
+			}}),
+			err: "unsupported metric exporter type: invalid",
+		},
+		{
+			name: "valid pull reader type, invalid prometheus exporter",
+			cfg: confmap.NewFromStringMap(map[string]any{"pull": PullMetricReader{
+				Exporter: MetricExporter{
+					"prometheus": "invalid",
+				},
+			}}),
+			err: "invalid exporter configuration: '' expected a map, got 'string'",
+		},
+		{
+			name: "valid pull reader type, valid prometheus exporter",
+			cfg: confmap.NewFromStringMap(map[string]any{"pull": PullMetricReader{
+				Exporter: MetricExporter{
+					"prometheus": Prometheus{},
+				},
+			}}),
+		},
+	}
+	for _, tt := range tests {
+		reader := make(MeterProviderJsonMetricReaders)
+		err := reader.Unmarshal(tt.cfg)
+		if len(tt.err) > 0 {
+			assert.ErrorContains(t, err, tt.err)
+		} else {
+			assert.NoError(t, err)
+		}
+	}
+}
diff --git a/service/telemetry_test.go b/service/telemetry_test.go
index 10cadbbaa7f..7b9dc1d202e 100644
--- a/service/telemetry_test.go
+++ b/service/telemetry_test.go
@@ -104,6 +104,7 @@ func TestTelemetryInit(t *testing.T) {
 		disableHighCard bool
 		expectedMetrics map[string]metricValue
 		extendedConfig  bool
+		cfg             *telemetry.Config
 	}{
 		{
 			name:    "UseOpenCensusForInternalMetrics",
@@ -187,26 +188,82 @@ func TestTelemetryInit(t *testing.T) {
 				},
 			},
 		},
-	} {
-		t.Run(tc.name, func(t *testing.T) {
-			tel := newColTelemetry(tc.useOtel, tc.disableHighCard, tc.extendedConfig)
-			buildInfo := component.NewDefaultBuildInfo()
-			cfg := telemetry.Config{
+		{
+			name:           "UseOTelWithSDKConfiguration",
+			extendedConfig: true,
+			cfg: &telemetry.Config{
+				Metrics: telemetry.MetricsConfig{
+					Level: configtelemetry.LevelDetailed,
+				},
 				Resource: map[string]*string{
 					semconv.AttributeServiceInstanceID: &testInstanceID,
 				},
-				Metrics: telemetry.MetricsConfig{
-					Level:   configtelemetry.LevelDetailed,
-					Address: testutil.GetAvailableLocalAddress(t),
+			},
+			expectedMetrics: map[string]metricValue{
+				metricPrefix + ocPrefix + counterName + "_total": {
+					value:  13,
+					labels: map[string]string{},
+				},
+				metricPrefix + otelPrefix + counterName + "_total": {
+					value:  13,
+					labels: map[string]string{},
+				},
+				metricPrefix + grpcPrefix + counterName + "_total": {
+					value: 11,
+					labels: map[string]string{
+						"net_sock_peer_addr": "",
+						"net_sock_peer_name": "",
+						"net_sock_peer_port": "",
+					},
+				},
+				metricPrefix + httpPrefix + counterName + "_total": {
+					value: 10,
+					labels: map[string]string{
+						"net_host_name": "",
+						"net_host_port": "",
+					},
+				},
+				metricPrefix + "target_info": {
+					value: 0,
+					labels: map[string]string{
+						"service_name":        "otelcol",
+						"service_version":     "latest",
+						"service_instance_id": testInstanceID,
+					},
 				},
+			},
+		},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			tel := newColTelemetry(tc.useOtel, tc.disableHighCard, tc.extendedConfig)
+			buildInfo := component.NewDefaultBuildInfo()
+			if tc.extendedConfig {
+				tc.cfg.Metrics.Readers = telemetry.MeterProviderJsonMetricReaders{
+					"pull/prometheus": telemetry.PullMetricReader{
+						Exporter: telemetry.MetricExporter{
+							"prometheus": testutil.GetAvailableLocalAddressPrometheus(t),
+						},
+					},
+				}
+			}
+			if tc.cfg == nil {
+				tc.cfg = &telemetry.Config{
+					Resource: map[string]*string{
+						semconv.AttributeServiceInstanceID: &testInstanceID,
+					},
+					Metrics: telemetry.MetricsConfig{
+						Level:   configtelemetry.LevelDetailed,
+						Address: testutil.GetAvailableLocalAddress(t),
+					},
+				}
 			}
-			otelRes := buildResource(buildInfo, cfg)
+			otelRes := buildResource(buildInfo, *tc.cfg)
 			res := pdataFromSdk(otelRes)
 			settings := component.TelemetrySettings{
 				Logger:   zap.NewNop(),
 				Resource: res,
 			}
-			err := tel.init(otelRes, settings, cfg, make(chan error))
+			err := tel.init(otelRes, settings, *tc.cfg, make(chan error))
 			require.NoError(t, err)
 			defer func() {
 				require.NoError(t, tel.shutdown())

From 38afdb75959cb7a6b99e8421a91910b13f70e14b Mon Sep 17 00:00:00 2001
From: Alex Boten <aboten@lightstep.com>
Date: Fri, 23 Jun 2023 08:57:54 -0700
Subject: [PATCH 03/10] Apply suggestions from code review

Co-authored-by: Pablo Baeyens <pbaeyens31+github@gmail.com>
---
 service/internal/proctelemetry/config.go | 4 ++--
 service/telemetry.go                     | 2 +-
 service/telemetry/config.go              | 4 ++--
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/service/internal/proctelemetry/config.go b/service/internal/proctelemetry/config.go
index 4f7b5f79a4f..34cb26110e6 100644
--- a/service/internal/proctelemetry/config.go
+++ b/service/internal/proctelemetry/config.go
@@ -65,7 +65,7 @@ func InitMetricReader(ctx context.Context, name string, reader any, asyncErrorCh
 		}
 		return initExporter(ctx, r.Exporter, asyncErrorChannel)
 	default:
-		return nil, nil, fmt.Errorf("unsupported metric reader type: %s", readerType)
+		return nil, nil, fmt.Errorf("unsupported metric reader type %q", readerType)
 	}
 }
 
@@ -174,7 +174,7 @@ func initExporter(_ context.Context, exporters telemetry.MetricExporter, asyncEr
 			}
 			return initPrometheusExporter(e, asyncErrorChannel)
 		default:
-			return nil, nil, fmt.Errorf("unsupported metric exporter type: %s", exporterType)
+			return nil, nil, fmt.Errorf("unsupported metric exporter type %q", exporterType)
 		}
 	}
 	return nil, nil, fmt.Errorf("no valid exporter: %v", exporters)
diff --git a/service/telemetry.go b/service/telemetry.go
index a1e8d337e51..99e98b34848 100644
--- a/service/telemetry.go
+++ b/service/telemetry.go
@@ -97,7 +97,7 @@ func (tel *telemetryInitializer) initMetrics(res *resource.Resource, logger *zap
 
 	if len(cfg.Metrics.Address) != 0 {
 		if tel.extendedConfig {
-			logger.Warn("service.telemetry.metrics.address is being deprecated in favor of service.telemetry.metrics.metric_readers")
+			logger.Warn("service::telemetry::metrics::address is being deprecated in favor of service::telemetry::metrics::metric_readers")
 		}
 		host, port, err := net.SplitHostPort(cfg.Metrics.Address)
 		if err != nil {
diff --git a/service/telemetry/config.go b/service/telemetry/config.go
index f45bd3040f2..fe1203dd5c5 100644
--- a/service/telemetry/config.go
+++ b/service/telemetry/config.go
@@ -160,11 +160,11 @@ func (mrs *MeterProviderJsonMetricReaders) Unmarshal(conf *confmap.Conf) error {
 					}
 					r.Exporter[key] = promExporter
 				default:
-					return fmt.Errorf("unsupported metric exporter type: %s", key)
+					return fmt.Errorf("unsupported metric exporter type %q", key)
 				}
 			}
 		default:
-			return fmt.Errorf("unsupported metric reader type: %s", readerType)
+			return fmt.Errorf("unsupported metric reader type %q", readerType)
 		}
 	}
 	return nil

From fdea1118c166b0e0ac81174f85ffe87aed583a49 Mon Sep 17 00:00:00 2001
From: Alex Boten <aboten@lightstep.com>
Date: Fri, 23 Jun 2023 09:04:18 -0700
Subject: [PATCH 04/10] fix test, typo in var name

Signed-off-by: Alex Boten <aboten@lightstep.com>
---
 service/internal/proctelemetry/config.go      | 4 ++--
 service/internal/proctelemetry/config_test.go | 2 +-
 service/telemetry/config_test.go              | 4 ++--
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/service/internal/proctelemetry/config.go b/service/internal/proctelemetry/config.go
index 34cb26110e6..c2d39212e2e 100644
--- a/service/internal/proctelemetry/config.go
+++ b/service/internal/proctelemetry/config.go
@@ -37,7 +37,7 @@ const (
 	pullMetricReader = "pull"
 
 	// supported exporters
-	prometheueExporter = "prometheus"
+	prometheusExporter = "prometheus"
 )
 
 var (
@@ -167,7 +167,7 @@ func initPrometheusExporter(prometheusConfig telemetry.Prometheus, asyncErrorCha
 func initExporter(_ context.Context, exporters telemetry.MetricExporter, asyncErrorChannel chan error) (sdkmetric.Reader, *http.Server, error) {
 	for exporterType, exporter := range exporters {
 		switch exporterType {
-		case prometheueExporter:
+		case prometheusExporter:
 			e, ok := exporter.(telemetry.Prometheus)
 			if !ok {
 				return nil, nil, fmt.Errorf("prometheus exporter invalid: %v", exporter)
diff --git a/service/internal/proctelemetry/config_test.go b/service/internal/proctelemetry/config_test.go
index 49edd31474e..bbe5b4b9163 100644
--- a/service/internal/proctelemetry/config_test.go
+++ b/service/internal/proctelemetry/config_test.go
@@ -30,7 +30,7 @@ func TestMetricReader(t *testing.T) {
 	}{
 		{
 			name: "noreader",
-			err:  errors.New("unsupported metric reader type: noreader"),
+			err:  errors.New("unsupported metric reader type \"noreader\""),
 		},
 		{
 			name: "pull/prometheus-invalid-config-no-host",
diff --git a/service/telemetry/config_test.go b/service/telemetry/config_test.go
index d07e2014b83..0d8667d6cf1 100644
--- a/service/telemetry/config_test.go
+++ b/service/telemetry/config_test.go
@@ -73,7 +73,7 @@ func TestUnmarshalMetricReaders(t *testing.T) {
 		{
 			name: "invalid config",
 			cfg:  confmap.NewFromStringMap(map[string]any{"invalid": "invalid"}),
-			err:  "unsupported metric reader type: invalid",
+			err:  "unsupported metric reader type \"invalid\"",
 		},
 		{
 			name: "valid reader type, invalid config",
@@ -91,7 +91,7 @@ func TestUnmarshalMetricReaders(t *testing.T) {
 					"invalid": "invalid",
 				},
 			}}),
-			err: "unsupported metric exporter type: invalid",
+			err: "unsupported metric exporter type \"invalid\"",
 		},
 		{
 			name: "valid pull reader type, invalid prometheus exporter",

From c64348c64dd5469b212a02e23c66cc9db2103002 Mon Sep 17 00:00:00 2001
From: Alex Boten <aboten@lightstep.com>
Date: Fri, 23 Jun 2023 10:11:46 -0700
Subject: [PATCH 05/10] remove unnecessary nil check, add check for conf being
 nil

Signed-off-by: Alex Boten <aboten@lightstep.com>
---
 service/telemetry/config.go | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/service/telemetry/config.go b/service/telemetry/config.go
index fe1203dd5c5..12cfbe0a705 100644
--- a/service/telemetry/config.go
+++ b/service/telemetry/config.go
@@ -125,7 +125,6 @@ type TracesConfig struct {
 
 // Validate checks whether the current configuration is valid
 func (c *Config) Validate() error {
-
 	// Check when service telemetry metric level is not none, the metrics address should not be empty
 	if c.Metrics.Level != configtelemetry.LevelNone && c.Metrics.Address == "" && len(c.Metrics.Readers) == 0 {
 		return fmt.Errorf("collector telemetry metric address should exist when metric level is not none")
@@ -135,12 +134,14 @@ func (c *Config) Validate() error {
 }
 
 func (mrs *MeterProviderJsonMetricReaders) Unmarshal(conf *confmap.Conf) error {
+	if conf == nil {
+		return nil
+	}
+
 	if err := conf.Unmarshal(mrs); err != nil {
 		return err
 	}
-	if *mrs == nil {
-		*mrs = make(MeterProviderJsonMetricReaders)
-	}
+
 	for key, reader := range *mrs {
 		readerType := strings.Split(key, "/")[0]
 		switch readerType {

From ff1b27b7a2e7d8fde9a169cef77c3357abfe7554 Mon Sep 17 00:00:00 2001
From: Alex Boten <aboten@lightstep.com>
Date: Thu, 29 Jun 2023 15:32:38 -0700
Subject: [PATCH 06/10] update metric_readers -> readers

Signed-off-by: Alex Boten <aboten@lightstep.com>
---
 .chloggen/codeboten_may-29-otlp-export.yaml   |  4 +--
 internal/testutil/testutil.go                 |  8 ++---
 service/internal/proctelemetry/config.go      | 19 +++--------
 service/internal/proctelemetry/config_test.go |  6 ++--
 service/telemetry.go                          |  6 ++--
 service/telemetry/config.go                   | 19 +++--------
 service/telemetry/config_test.go              | 34 ++++++++-----------
 service/telemetry_test.go                     |  4 +--
 8 files changed, 38 insertions(+), 62 deletions(-)

diff --git a/.chloggen/codeboten_may-29-otlp-export.yaml b/.chloggen/codeboten_may-29-otlp-export.yaml
index a22bbae5bd7..2960d9ade53 100755
--- a/.chloggen/codeboten_may-29-otlp-export.yaml
+++ b/.chloggen/codeboten_may-29-otlp-export.yaml
@@ -5,7 +5,7 @@ change_type: enhancement
 component: service
 
 # A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
-note: "add ability to configure prometheus export via `metric_readers`"
+note: "add ability to configure prometheus export via `readers`"
 
 # One or more tracking issues or pull requests related to the change
 issues: [7641]
@@ -15,7 +15,7 @@ issues: [7641]
 # Use pipe (|) for multiline entries.
 subtext: |
   This enables end users to configure additional prometheus exporters for the collector's telemetry
-  via the `metric_readers` configuration option. Configuring prometheus through the existing method
+  via the `readers` configuration option. Configuring prometheus through the existing method
   of setting the service::metrics::address will continue to work, and only log a warning for users
   who have enabled the `telemetry.useOtelWithSDKConfigurationForInternalTelemetry` feature gate.
 
diff --git a/internal/testutil/testutil.go b/internal/testutil/testutil.go
index 4bb1a698374..427e51d2e19 100644
--- a/internal/testutil/testutil.go
+++ b/internal/testutil/testutil.go
@@ -57,17 +57,17 @@ func GetAvailableLocalAddress(t testing.TB) string {
 	return endpoint
 }
 
-func GetAvailableLocalAddressPrometheus(t testing.TB) telemetry.Prometheus {
+func GetAvailableLocalAddressPrometheus(t testing.TB) *telemetry.Prometheus {
 	address := GetAvailableLocalAddress(t)
 	host, port, err := net.SplitHostPort(address)
 	if err != nil {
-		return telemetry.Prometheus{}
+		return nil
 	}
 	portInt, err := strconv.Atoi(port)
 	if err != nil {
-		return telemetry.Prometheus{}
+		return nil
 	}
-	return telemetry.Prometheus{
+	return &telemetry.Prometheus{
 		Host: &host,
 		Port: &portInt,
 	}
diff --git a/service/internal/proctelemetry/config.go b/service/internal/proctelemetry/config.go
index c2d39212e2e..3c03a5447dc 100644
--- a/service/internal/proctelemetry/config.go
+++ b/service/internal/proctelemetry/config.go
@@ -139,7 +139,7 @@ func cardinalityFilter(kvs ...attribute.KeyValue) attribute.Filter {
 	}
 }
 
-func initPrometheusExporter(prometheusConfig telemetry.Prometheus, asyncErrorChannel chan error) (sdkmetric.Reader, *http.Server, error) {
+func initPrometheusExporter(prometheusConfig *telemetry.Prometheus, asyncErrorChannel chan error) (sdkmetric.Reader, *http.Server, error) {
 	promRegistry := prometheus.NewRegistry()
 	if prometheusConfig.Host == nil {
 		return nil, nil, fmt.Errorf("host must be specified")
@@ -164,18 +164,9 @@ func initPrometheusExporter(prometheusConfig telemetry.Prometheus, asyncErrorCha
 	return exporter, InitPrometheusServer(promRegistry, fmt.Sprintf("%s:%d", *prometheusConfig.Host, *prometheusConfig.Port), asyncErrorChannel), nil
 }
 
-func initExporter(_ context.Context, exporters telemetry.MetricExporter, asyncErrorChannel chan error) (sdkmetric.Reader, *http.Server, error) {
-	for exporterType, exporter := range exporters {
-		switch exporterType {
-		case prometheusExporter:
-			e, ok := exporter.(telemetry.Prometheus)
-			if !ok {
-				return nil, nil, fmt.Errorf("prometheus exporter invalid: %v", exporter)
-			}
-			return initPrometheusExporter(e, asyncErrorChannel)
-		default:
-			return nil, nil, fmt.Errorf("unsupported metric exporter type %q", exporterType)
-		}
+func initExporter(_ context.Context, exporter telemetry.MetricExporter, asyncErrorChannel chan error) (sdkmetric.Reader, *http.Server, error) {
+	if exporter.Prometheus != nil {
+		return initPrometheusExporter(exporter.Prometheus, asyncErrorChannel)
 	}
-	return nil, nil, fmt.Errorf("no valid exporter: %v", exporters)
+	return nil, nil, fmt.Errorf("no valid exporter: %v", exporter)
 }
diff --git a/service/internal/proctelemetry/config_test.go b/service/internal/proctelemetry/config_test.go
index bbe5b4b9163..41d706cd99f 100644
--- a/service/internal/proctelemetry/config_test.go
+++ b/service/internal/proctelemetry/config_test.go
@@ -36,7 +36,7 @@ func TestMetricReader(t *testing.T) {
 			name: "pull/prometheus-invalid-config-no-host",
 			reader: telemetry.PullMetricReader{
 				Exporter: telemetry.MetricExporter{
-					"prometheus": telemetry.Prometheus{},
+					Prometheus: &telemetry.Prometheus{},
 				},
 			},
 			err: errors.New("host must be specified"),
@@ -45,7 +45,7 @@ func TestMetricReader(t *testing.T) {
 			name: "pull/prometheus-invalid-config-no-port",
 			reader: telemetry.PullMetricReader{
 				Exporter: telemetry.MetricExporter{
-					"prometheus": telemetry.Prometheus{
+					Prometheus: &telemetry.Prometheus{
 						Host: strPtr("locahost"),
 					},
 				},
@@ -56,7 +56,7 @@ func TestMetricReader(t *testing.T) {
 			name: "pull/prometheus-invalid-config-no-port",
 			reader: telemetry.PullMetricReader{
 				Exporter: telemetry.MetricExporter{
-					"prometheus": telemetry.Prometheus{
+					Prometheus: &telemetry.Prometheus{
 						Host: strPtr("locahost"),
 						Port: intPtr(8080),
 					},
diff --git a/service/telemetry.go b/service/telemetry.go
index 99e98b34848..58df291f636 100644
--- a/service/telemetry.go
+++ b/service/telemetry.go
@@ -97,7 +97,7 @@ func (tel *telemetryInitializer) initMetrics(res *resource.Resource, logger *zap
 
 	if len(cfg.Metrics.Address) != 0 {
 		if tel.extendedConfig {
-			logger.Warn("service::telemetry::metrics::address is being deprecated in favor of service::telemetry::metrics::metric_readers")
+			logger.Warn("service::telemetry::metrics::address is being deprecated in favor of service::telemetry::metrics::readers")
 		}
 		host, port, err := net.SplitHostPort(cfg.Metrics.Address)
 		if err != nil {
@@ -108,11 +108,11 @@ func (tel *telemetryInitializer) initMetrics(res *resource.Resource, logger *zap
 			return err
 		}
 		if cfg.Metrics.Readers == nil {
-			cfg.Metrics.Readers = telemetry.MeterProviderJsonMetricReaders{}
+			cfg.Metrics.Readers = telemetry.MeterProviderJsonReaders{}
 		}
 		cfg.Metrics.Readers["pull/serviceaddress"] = telemetry.PullMetricReader{
 			Exporter: telemetry.MetricExporter{
-				"prometheus": telemetry.Prometheus{
+				Prometheus: &telemetry.Prometheus{
 					Host: &host,
 					Port: &portInt,
 				},
diff --git a/service/telemetry/config.go b/service/telemetry/config.go
index 12cfbe0a705..9c07cc56cdd 100644
--- a/service/telemetry/config.go
+++ b/service/telemetry/config.go
@@ -111,7 +111,7 @@ type MetricsConfig struct {
 
 	// Readers allow configuration of metric readers to emit metrics to
 	// any number of supported backends.
-	Readers MeterProviderJsonMetricReaders `mapstructure:"metric_readers"`
+	Readers MeterProviderJsonReaders `mapstructure:"readers"`
 }
 
 // TracesConfig exposes the common Telemetry configuration for collector's internal spans.
@@ -133,7 +133,7 @@ func (c *Config) Validate() error {
 	return nil
 }
 
-func (mrs *MeterProviderJsonMetricReaders) Unmarshal(conf *confmap.Conf) error {
+func (mrs *MeterProviderJsonReaders) Unmarshal(conf *confmap.Conf) error {
 	if conf == nil {
 		return nil
 	}
@@ -151,19 +151,10 @@ func (mrs *MeterProviderJsonMetricReaders) Unmarshal(conf *confmap.Conf) error {
 				return fmt.Errorf("invalid pull metric reader configuration: %w", err)
 			}
 			(*mrs)[key] = r
-
-			for key, exporter := range r.Exporter {
-				switch key {
-				case "prometheus":
-					var promExporter Prometheus
-					if err := mapstructure.Decode(exporter, &promExporter); err != nil {
-						return fmt.Errorf("invalid exporter configuration: %w", err)
-					}
-					r.Exporter[key] = promExporter
-				default:
-					return fmt.Errorf("unsupported metric exporter type %q", key)
-				}
+			if r.Exporter.Prometheus == nil {
+				return fmt.Errorf("invalid exporter configuration")
 			}
+
 		default:
 			return fmt.Errorf("unsupported metric reader type %q", readerType)
 		}
diff --git a/service/telemetry/config_test.go b/service/telemetry/config_test.go
index 0d8667d6cf1..e48f0333dbd 100644
--- a/service/telemetry/config_test.go
+++ b/service/telemetry/config_test.go
@@ -43,7 +43,7 @@ func TestLoadConfig(t *testing.T) {
 			cfg: &Config{
 				Metrics: MetricsConfig{
 					Level: configtelemetry.LevelBasic,
-					Readers: MeterProviderJsonMetricReaders{
+					Readers: MeterProviderJsonReaders{
 						"pull/prometheus": PullMetricReader{},
 					},
 				},
@@ -83,41 +83,35 @@ func TestUnmarshalMetricReaders(t *testing.T) {
 		{
 			name: "valid pull reader type, no exporter",
 			cfg:  confmap.NewFromStringMap(map[string]any{"pull": PullMetricReader{}}),
+			err:  "invalid exporter configuration",
 		},
 		{
 			name: "valid pull reader type, invalid exporter",
 			cfg: confmap.NewFromStringMap(map[string]any{"pull": PullMetricReader{
 				Exporter: MetricExporter{
-					"invalid": "invalid",
+					Prometheus: nil,
 				},
 			}}),
-			err: "unsupported metric exporter type \"invalid\"",
-		},
-		{
-			name: "valid pull reader type, invalid prometheus exporter",
-			cfg: confmap.NewFromStringMap(map[string]any{"pull": PullMetricReader{
-				Exporter: MetricExporter{
-					"prometheus": "invalid",
-				},
-			}}),
-			err: "invalid exporter configuration: '' expected a map, got 'string'",
+			err: "invalid exporter configuration",
 		},
 		{
 			name: "valid pull reader type, valid prometheus exporter",
 			cfg: confmap.NewFromStringMap(map[string]any{"pull": PullMetricReader{
 				Exporter: MetricExporter{
-					"prometheus": Prometheus{},
+					Prometheus: &Prometheus{},
 				},
 			}}),
 		},
 	}
 	for _, tt := range tests {
-		reader := make(MeterProviderJsonMetricReaders)
-		err := reader.Unmarshal(tt.cfg)
-		if len(tt.err) > 0 {
-			assert.ErrorContains(t, err, tt.err)
-		} else {
-			assert.NoError(t, err)
-		}
+		t.Run(tt.name, func(t *testing.T) {
+			reader := make(MeterProviderJsonReaders)
+			err := reader.Unmarshal(tt.cfg)
+			if len(tt.err) > 0 {
+				assert.ErrorContains(t, err, tt.err)
+			} else {
+				assert.NoError(t, err)
+			}
+		})
 	}
 }
diff --git a/service/telemetry_test.go b/service/telemetry_test.go
index 7b9dc1d202e..e60b4a01278 100644
--- a/service/telemetry_test.go
+++ b/service/telemetry_test.go
@@ -238,10 +238,10 @@ func TestTelemetryInit(t *testing.T) {
 			tel := newColTelemetry(tc.useOtel, tc.disableHighCard, tc.extendedConfig)
 			buildInfo := component.NewDefaultBuildInfo()
 			if tc.extendedConfig {
-				tc.cfg.Metrics.Readers = telemetry.MeterProviderJsonMetricReaders{
+				tc.cfg.Metrics.Readers = telemetry.MeterProviderJsonReaders{
 					"pull/prometheus": telemetry.PullMetricReader{
 						Exporter: telemetry.MetricExporter{
-							"prometheus": testutil.GetAvailableLocalAddressPrometheus(t),
+							Prometheus: testutil.GetAvailableLocalAddressPrometheus(t),
 						},
 					},
 				}

From 74daae055c6db808cf6ecbac572daac2bb444056 Mon Sep 17 00:00:00 2001
From: Alex Boten <aboten@lightstep.com>
Date: Fri, 7 Jul 2023 14:31:43 -0700
Subject: [PATCH 07/10] add test case

Signed-off-by: Alex Boten <aboten@lightstep.com>
---
 service/telemetry/config_test.go | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/service/telemetry/config_test.go b/service/telemetry/config_test.go
index e48f0333dbd..d8f7e5665ba 100644
--- a/service/telemetry/config_test.go
+++ b/service/telemetry/config_test.go
@@ -102,6 +102,14 @@ func TestUnmarshalMetricReaders(t *testing.T) {
 				},
 			}}),
 		},
+		{
+			name: "valid pull reader type with name, valid prometheus exporter",
+			cfg: confmap.NewFromStringMap(map[string]any{"pull/prometheus1": PullMetricReader{
+				Exporter: MetricExporter{
+					Prometheus: &Prometheus{},
+				},
+			}}),
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {

From 8d7e3f7ed15ce10a31e1d15afe1c277f5fc06a00 Mon Sep 17 00:00:00 2001
From: Alex Boten <aboten@lightstep.com>
Date: Fri, 7 Jul 2023 14:35:43 -0700
Subject: [PATCH 08/10] update comment w/ issue number

Signed-off-by: Alex Boten <aboten@lightstep.com>
---
 .chloggen/codeboten_may-29-otlp-export.yaml   | 15 +++---
 extension/zpagesextension/go.mod              |  1 +
 extension/zpagesextension/go.sum              | 12 +++++
 go.mod                                        |  2 +-
 service/internal/proctelemetry/config.go      | 26 ++--------
 service/internal/proctelemetry/config_test.go | 42 +++++++++-------
 service/telemetry.go                          | 25 +++++-----
 service/telemetry/config.go                   | 41 +++++++---------
 service/telemetry/config_test.go              | 48 +++++++++++++------
 service/telemetry_test.go                     | 10 ++--
 10 files changed, 120 insertions(+), 102 deletions(-)

diff --git a/.chloggen/codeboten_may-29-otlp-export.yaml b/.chloggen/codeboten_may-29-otlp-export.yaml
index 2960d9ade53..19f29c21a71 100755
--- a/.chloggen/codeboten_may-29-otlp-export.yaml
+++ b/.chloggen/codeboten_may-29-otlp-export.yaml
@@ -1,21 +1,20 @@
 # One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
-change_type: enhancement
+change_type: breaking
 
 # The name of the component, or a single word describing the area of concern, (e.g. otlpreceiver)
 component: service
 
 # A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
-note: "add ability to configure prometheus export via `readers`"
+note: Enable configuration of collector telemetry through prometheus reader
 
 # One or more tracking issues or pull requests related to the change
-issues: [7641]
+issues: []
 
 # (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: |
-  This enables end users to configure additional prometheus exporters for the collector's telemetry
-  via the `readers` configuration option. Configuring prometheus through the existing method
-  of setting the service::metrics::address will continue to work, and only log a warning for users
-  who have enabled the `telemetry.useOtelWithSDKConfigurationForInternalTelemetry` feature gate.
-
+  These options are still experimental. To enable them, users must enable both
+  `telemetry.useOtelForInternalMetrics` and `telemetry.useOtelWithSDKConfigurationForInternalTelemetry`
+  feature gates. This change updates `metric_readers` to `readers` to align with the configuration
+  working group.
diff --git a/extension/zpagesextension/go.mod b/extension/zpagesextension/go.mod
index f5c216fcaa2..ce17f4c6893 100644
--- a/extension/zpagesextension/go.mod
+++ b/extension/zpagesextension/go.mod
@@ -27,6 +27,7 @@ require (
 	github.com/mitchellh/mapstructure v1.5.1-0.20220423185008-bf980b35cac4 // indirect
 	github.com/mitchellh/reflectwalk v1.0.2 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
+	go.opencensus.io v0.24.0 // indirect
 	go.opentelemetry.io/collector/config/configtelemetry v0.81.0 // indirect
 	go.opentelemetry.io/collector/featuregate v1.0.0-rcv0013 // indirect
 	go.opentelemetry.io/collector/pdata v1.0.0-rcv0013 // indirect
diff --git a/extension/zpagesextension/go.sum b/extension/zpagesextension/go.sum
index 1cabf3a5374..0d3125ffc94 100644
--- a/extension/zpagesextension/go.sum
+++ b/extension/zpagesextension/go.sum
@@ -66,6 +66,8 @@ github.com/gogo/protobuf v1.1.1/go.mod h1:r8qH/GZQm5c6nD/R0oafs1akxWv10x8SbQlK7a
 github.com/gogo/protobuf v1.3.2 h1:Ov1cvc58UF3b5XjBnZv7+opcTcQFZebYjWzi34vdm4Q=
 github.com/gogo/protobuf v1.3.2/go.mod h1:P1XiOD3dCwIKUDQYPy72D8LYyHL2YPYrpS2s69NZV8Q=
 github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b/go.mod h1:SBH7ygxi8pfUlaOkMMuAQtPIUF8ecWP5IEl/CR7VP2Q=
+github.com/golang/groupcache v0.0.0-20200121045136-8c9f03a8e57e/go.mod h1:cIg4eruTrX1D+g88fzRXU5OdNfaM+9IcxsU14FzY7Hc=
+github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da h1:oI5xCqsCo564l8iNU+DwB5epxmsaqB+rhGL0m5jtYqE=
 github.com/golang/mock v1.1.1/go.mod h1:oTYuIxOrZwtPieC+H1uAHpcLFnEyAGVDL/k47Jfbm0A=
 github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/golang/protobuf v1.3.1/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
@@ -90,6 +92,7 @@ github.com/google/go-cmp v0.3.0/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMyw
 github.com/google/go-cmp v0.3.1/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
 github.com/google/go-cmp v0.4.0/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.5.0/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/google/go-cmp v0.5.3/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.5.4/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.5.6/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
@@ -233,11 +236,16 @@ github.com/sirupsen/logrus v1.6.0/go.mod h1:7uNnSEd1DgxDLC74fIahvMZmmYsHGZGEOFrf
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
+github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
+github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
 github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
 github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
 github.com/yuin/goldmark v1.1.27/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
@@ -246,6 +254,8 @@ github.com/yuin/goldmark v1.3.5/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1
 go.etcd.io/etcd/api/v3 v3.5.4/go.mod h1:5GB2vv4A4AOn3yk7MftYGHkUfGtDHnEraIjym4dYz5A=
 go.etcd.io/etcd/client/pkg/v3 v3.5.4/go.mod h1:IJHfcCEKxYu1Os13ZdwCwIUTUVGYTSAM3YSwc9/Ac1g=
 go.etcd.io/etcd/client/v3 v3.5.4/go.mod h1:ZaRkVgBZC+L+dLCjTcF1hRXpgZXQPOvnA/Ak/gq3kiY=
+go.opencensus.io v0.24.0 h1:y73uSU6J157QMP2kn2r30vwW1A2W2WFwSCGnAVxeaD0=
+go.opencensus.io v0.24.0/go.mod h1:vNK8G9p7aAivkbmorf4v+7Hgx+Zs0yY+0fOtgBfjQKo=
 go.opentelemetry.io/contrib/zpages v0.42.0 h1:hFscXKQ9PTjyIVmAr6zIV8cMoiEeR9lPIwPVqHi8+5Q=
 go.opentelemetry.io/contrib/zpages v0.42.0/go.mod h1:qRJBEfB0iwRKrYImq5qfwTolmY8HXvZBRucvhuTVQZw=
 go.opentelemetry.io/otel v1.16.0 h1:Z7GVAX/UkAXPKsy94IU+i6thsQS4nb7LviLpnaNeW8s=
@@ -294,6 +304,7 @@ golang.org/x/net v0.0.0-20200226121028-0de0cce0169b/go.mod h1:z5CRVTTTmAJ677TzLL
 golang.org/x/net v0.0.0-20200625001655-4c5254603344/go.mod h1:/O7V0waA8r7cgGh81Ro3o1hOxt32SMVPicZroKQ2sZA=
 golang.org/x/net v0.0.0-20200822124328-c89045814202/go.mod h1:/O7V0waA8r7cgGh81Ro3o1hOxt32SMVPicZroKQ2sZA=
 golang.org/x/net v0.0.0-20201021035429-f5854403a974/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
+golang.org/x/net v0.0.0-20201110031124-69a78807bb2b/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
 golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
 golang.org/x/net v0.0.0-20210405180319-a5a99cb37ef4/go.mod h1:p54w0d4576C0XHj96bSt6lcn1PtDYWL6XObtHCRCNQM=
 golang.org/x/net v0.0.0-20210410081132-afb366fc7cd1/go.mod h1:9tjilg8BloeKEkVJvy7fQ90B1CfIiPueXVOjqfkSzI8=
@@ -385,6 +396,7 @@ google.golang.org/grpc v1.23.0/go.mod h1:Y5yQAOtifL1yxbo5wqy6BxZv8vAUGQwXBOALyac
 google.golang.org/grpc v1.25.1/go.mod h1:c3i+UQWmh7LiEpx4sFZnkU36qjEYZ0imhYfXVyQciAY=
 google.golang.org/grpc v1.27.0/go.mod h1:qbnxyOmOxrQa7FizSgH+ReBfzJrCY1pSN7KXBS8abTk=
 google.golang.org/grpc v1.33.1/go.mod h1:fr5YgcSWrqhRRxogOsw7RzIpsmvOZ6IcH4kBYTpR3n0=
+google.golang.org/grpc v1.33.2/go.mod h1:JMHMWHQWaTccqQQlmk3MJZS+GWXOdAesneDmEnv2fbc=
 google.golang.org/grpc v1.38.0/go.mod h1:NREThFqKR1f3iQ6oBuvc5LadQuXVGo9rkm5ZGrQdJfM=
 google.golang.org/grpc v1.56.2 h1:fVRFRnXvU+x6C4IlHZewvJOVHoOv1TUuQyoRsYnB4bI=
 google.golang.org/grpc v1.56.2/go.mod h1:I9bI3vqKfayGqPUAwGdOSu7kt6oIJLixfffKrpXqQ9s=
diff --git a/go.mod b/go.mod
index a58580db4bb..aa4d1a37151 100644
--- a/go.mod
+++ b/go.mod
@@ -5,7 +5,6 @@ go 1.19
 require (
 	contrib.go.opencensus.io/exporter/prometheus v0.4.2
 	github.com/google/uuid v1.3.0
-	github.com/mitchellh/mapstructure v1.5.1-0.20220423185008-bf980b35cac4
 	github.com/prometheus/client_golang v1.16.0
 	github.com/prometheus/client_model v0.4.0
 	github.com/prometheus/common v0.44.0
@@ -62,6 +61,7 @@ require (
 	github.com/lufia/plan9stats v0.0.0-20211012122336-39d0f177ccd0 // indirect
 	github.com/matttproud/golang_protobuf_extensions v1.0.4 // indirect
 	github.com/mitchellh/copystructure v1.2.0 // indirect
+	github.com/mitchellh/mapstructure v1.5.1-0.20220423185008-bf980b35cac4 // indirect
 	github.com/mitchellh/reflectwalk v1.0.2 // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect
diff --git a/service/internal/proctelemetry/config.go b/service/internal/proctelemetry/config.go
index 3c03a5447dc..67ce38fc377 100644
--- a/service/internal/proctelemetry/config.go
+++ b/service/internal/proctelemetry/config.go
@@ -8,7 +8,6 @@ import (
 	"errors"
 	"fmt"
 	"net/http"
-	"strings"
 
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/promhttp"
@@ -32,12 +31,6 @@ const (
 
 	// http Instrumentation Name
 	HTTPInstrumentation = "go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
-
-	// supported metric readers
-	pullMetricReader = "pull"
-
-	// supported exporters
-	prometheusExporter = "prometheus"
 )
 
 var (
@@ -55,18 +48,11 @@ var (
 	}
 )
 
-func InitMetricReader(ctx context.Context, name string, reader any, asyncErrorChannel chan error) (sdkmetric.Reader, *http.Server, error) {
-	readerType := strings.Split(name, "/")[0]
-	switch readerType {
-	case pullMetricReader:
-		r, ok := reader.(telemetry.PullMetricReader)
-		if !ok {
-			return nil, nil, fmt.Errorf("invalid metric reader configuration: %v", reader)
-		}
-		return initExporter(ctx, r.Exporter, asyncErrorChannel)
-	default:
-		return nil, nil, fmt.Errorf("unsupported metric reader type %q", readerType)
+func InitMetricReader(ctx context.Context, reader telemetry.MetricReader, asyncErrorChannel chan error) (sdkmetric.Reader, *http.Server, error) {
+	if reader.Pull != nil {
+		return initExporter(ctx, reader.Pull.Exporter, asyncErrorChannel)
 	}
+	return nil, nil, fmt.Errorf("unsupported metric reader type %v", reader)
 }
 
 func InitOpenTelemetry(res *resource.Resource, options []sdkmetric.Option, disableHighCardinality bool) (*sdkmetric.MeterProvider, error) {
@@ -148,11 +134,9 @@ func initPrometheusExporter(prometheusConfig *telemetry.Prometheus, asyncErrorCh
 		return nil, nil, fmt.Errorf("port must be specified")
 	}
 	wrappedRegisterer := prometheus.WrapRegistererWithPrefix("otelcol_", promRegistry)
-	// We can remove `otelprom.WithoutUnits()` when the otel-go start exposing prometheus metrics using the OpenMetrics format
-	// which includes metric units that prometheusreceiver uses to trim unit's suffixes from metric names.
-	// https://github.com/open-telemetry/opentelemetry-go/issues/3468
 	exporter, err := otelprom.New(
 		otelprom.WithRegisterer(wrappedRegisterer),
+		// https://github.com/open-telemetry/opentelemetry-collector/issues/8043
 		otelprom.WithoutUnits(),
 		// Disabled for the moment until this becomes stable, and we are ready to break backwards compatibility.
 		otelprom.WithoutScopeInfo())
diff --git a/service/internal/proctelemetry/config_test.go b/service/internal/proctelemetry/config_test.go
index 41d706cd99f..474904c8973 100644
--- a/service/internal/proctelemetry/config_test.go
+++ b/service/internal/proctelemetry/config_test.go
@@ -24,29 +24,33 @@ func intPtr(i int) *int {
 func TestMetricReader(t *testing.T) {
 	testCases := []struct {
 		name   string
-		reader any
+		reader telemetry.MetricReader
 		args   any
 		err    error
 	}{
 		{
 			name: "noreader",
-			err:  errors.New("unsupported metric reader type \"noreader\""),
+			err:  errors.New("unsupported metric reader type {<nil> <nil>}"),
 		},
 		{
 			name: "pull/prometheus-invalid-config-no-host",
-			reader: telemetry.PullMetricReader{
-				Exporter: telemetry.MetricExporter{
-					Prometheus: &telemetry.Prometheus{},
+			reader: telemetry.MetricReader{
+				Pull: &telemetry.PullMetricReader{
+					Exporter: telemetry.MetricExporter{
+						Prometheus: &telemetry.Prometheus{},
+					},
 				},
 			},
 			err: errors.New("host must be specified"),
 		},
 		{
 			name: "pull/prometheus-invalid-config-no-port",
-			reader: telemetry.PullMetricReader{
-				Exporter: telemetry.MetricExporter{
-					Prometheus: &telemetry.Prometheus{
-						Host: strPtr("locahost"),
+			reader: telemetry.MetricReader{
+				Pull: &telemetry.PullMetricReader{
+					Exporter: telemetry.MetricExporter{
+						Prometheus: &telemetry.Prometheus{
+							Host: strPtr("locahost"),
+						},
 					},
 				},
 			},
@@ -54,20 +58,22 @@ func TestMetricReader(t *testing.T) {
 		},
 		{
 			name: "pull/prometheus-invalid-config-no-port",
-			reader: telemetry.PullMetricReader{
-				Exporter: telemetry.MetricExporter{
-					Prometheus: &telemetry.Prometheus{
-						Host: strPtr("locahost"),
-						Port: intPtr(8080),
+			reader: telemetry.MetricReader{
+				Pull: &telemetry.PullMetricReader{
+					Exporter: telemetry.MetricExporter{
+						Prometheus: &telemetry.Prometheus{
+							Host: strPtr("locahost"),
+							Port: intPtr(8080),
+						},
 					},
 				},
 			},
 		},
 	}
-	for _, tc := range testCases {
-		t.Run(tc.name, func(t *testing.T) {
-			_, _, err := InitMetricReader(context.Background(), tc.name, tc.reader, make(chan error))
-			assert.Equal(t, tc.err, err)
+	for _, tt := range testCases {
+		t.Run(tt.name, func(t *testing.T) {
+			_, _, err := InitMetricReader(context.Background(), tt.reader, make(chan error))
+			assert.Equal(t, tt.err, err)
 		})
 	}
 }
diff --git a/service/telemetry.go b/service/telemetry.go
index 58df291f636..519e6bf987a 100644
--- a/service/telemetry.go
+++ b/service/telemetry.go
@@ -108,26 +108,25 @@ func (tel *telemetryInitializer) initMetrics(res *resource.Resource, logger *zap
 			return err
 		}
 		if cfg.Metrics.Readers == nil {
-			cfg.Metrics.Readers = telemetry.MeterProviderJsonReaders{}
+			cfg.Metrics.Readers = []telemetry.MetricReader{}
 		}
-		cfg.Metrics.Readers["pull/serviceaddress"] = telemetry.PullMetricReader{
-			Exporter: telemetry.MetricExporter{
-				Prometheus: &telemetry.Prometheus{
-					Host: &host,
-					Port: &portInt,
+		cfg.Metrics.Readers = append(cfg.Metrics.Readers, telemetry.MetricReader{
+			Pull: &telemetry.PullMetricReader{
+				Exporter: telemetry.MetricExporter{
+					Prometheus: &telemetry.Prometheus{
+						Host: &host,
+						Port: &portInt,
+					},
 				},
 			},
-		}
+		})
 	}
 
 	metricproducer.GlobalManager().AddProducer(tel.ocRegistry)
 	opts := []sdkmetric.Option{}
-	for name, reader := range cfg.Metrics.Readers {
-		// @codeboten: server returned here only happens when a pull based metric
-		// reader is configured, this could be refactored to pass in a
-		// func to add the server to the list of servers. another thing that would
-		// be nice is not to have to pass down the asyncErrorChannel
-		r, server, err := proctelemetry.InitMetricReader(context.Background(), name, reader, asyncErrorChannel)
+	for _, reader := range cfg.Metrics.Readers {
+		// https://github.com/open-telemetry/opentelemetry-collector/issues/8045
+		r, server, err := proctelemetry.InitMetricReader(context.Background(), reader, asyncErrorChannel)
 		if err != nil {
 			return err
 		}
diff --git a/service/telemetry/config.go b/service/telemetry/config.go
index 9c07cc56cdd..58c3f882449 100644
--- a/service/telemetry/config.go
+++ b/service/telemetry/config.go
@@ -5,13 +5,12 @@ package telemetry // import "go.opentelemetry.io/collector/service/telemetry"
 
 import (
 	"fmt"
-	"strings"
 
-	"github.com/mitchellh/mapstructure"
 	"go.uber.org/zap/zapcore"
 
 	"go.opentelemetry.io/collector/config/configtelemetry"
 	"go.opentelemetry.io/collector/confmap"
+	"go.opentelemetry.io/collector/internal/obsreportconfig"
 )
 
 // Config defines the configurable settings for service telemetry.
@@ -111,7 +110,7 @@ type MetricsConfig struct {
 
 	// Readers allow configuration of metric readers to emit metrics to
 	// any number of supported backends.
-	Readers MeterProviderJsonReaders `mapstructure:"readers"`
+	Readers []MetricReader `mapstructure:"readers"`
 }
 
 // TracesConfig exposes the common Telemetry configuration for collector's internal spans.
@@ -127,37 +126,33 @@ type TracesConfig struct {
 func (c *Config) Validate() error {
 	// Check when service telemetry metric level is not none, the metrics address should not be empty
 	if c.Metrics.Level != configtelemetry.LevelNone && c.Metrics.Address == "" && len(c.Metrics.Readers) == 0 {
-		return fmt.Errorf("collector telemetry metric address should exist when metric level is not none")
+		return fmt.Errorf("collector telemetry metric address or reader should exist when metric level is not none")
 	}
 
 	return nil
 }
 
-func (mrs *MeterProviderJsonReaders) Unmarshal(conf *confmap.Conf) error {
+func (mr *MetricReader) Unmarshal(conf *confmap.Conf) error {
+	if !obsreportconfig.UseOtelWithSDKConfigurationForInternalTelemetryFeatureGate.IsEnabled() {
+		fmt.Println(obsreportconfig.UseOtelWithSDKConfigurationForInternalTelemetryFeatureGate.IsEnabled())
+		// only unmarshal if feature gate is enabled
+		return nil
+	}
+
 	if conf == nil {
 		return nil
 	}
 
-	if err := conf.Unmarshal(mrs); err != nil {
-		return err
+	if err := conf.Unmarshal(mr); err != nil {
+		return fmt.Errorf("invalid metric reader configuration: %w", err)
 	}
 
-	for key, reader := range *mrs {
-		readerType := strings.Split(key, "/")[0]
-		switch readerType {
-		case "pull":
-			var r PullMetricReader
-			if err := mapstructure.Decode(reader, &r); err != nil {
-				return fmt.Errorf("invalid pull metric reader configuration: %w", err)
-			}
-			(*mrs)[key] = r
-			if r.Exporter.Prometheus == nil {
-				return fmt.Errorf("invalid exporter configuration")
-			}
-
-		default:
-			return fmt.Errorf("unsupported metric reader type %q", readerType)
+	if mr.Pull != nil {
+		if mr.Pull.Exporter.Prometheus == nil {
+			return fmt.Errorf("invalid exporter configuration")
 		}
+		return nil
 	}
-	return nil
+
+	return fmt.Errorf("unsupported metric reader type %s", conf.AllKeys())
 }
diff --git a/service/telemetry/config_test.go b/service/telemetry/config_test.go
index d8f7e5665ba..c17523b1174 100644
--- a/service/telemetry/config_test.go
+++ b/service/telemetry/config_test.go
@@ -7,9 +7,12 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 
 	"go.opentelemetry.io/collector/config/configtelemetry"
 	"go.opentelemetry.io/collector/confmap"
+	"go.opentelemetry.io/collector/featuregate"
+	"go.opentelemetry.io/collector/internal/obsreportconfig"
 )
 
 func TestLoadConfig(t *testing.T) {
@@ -43,8 +46,8 @@ func TestLoadConfig(t *testing.T) {
 			cfg: &Config{
 				Metrics: MetricsConfig{
 					Level: configtelemetry.LevelBasic,
-					Readers: MeterProviderJsonReaders{
-						"pull/prometheus": PullMetricReader{},
+					Readers: []MetricReader{
+						{Pull: &PullMetricReader{}},
 					},
 				},
 			},
@@ -64,7 +67,23 @@ func TestLoadConfig(t *testing.T) {
 	}
 }
 
-func TestUnmarshalMetricReaders(t *testing.T) {
+// Force the state of feature gate for a test
+func setFeatureGateForTest(t testing.TB, gate *featuregate.Gate, enabled bool) func() {
+	originalValue := gate.IsEnabled()
+	require.NoError(t, featuregate.GlobalRegistry().Set(gate.ID(), enabled))
+	return func() {
+		require.NoError(t, featuregate.GlobalRegistry().Set(gate.ID(), originalValue))
+	}
+}
+
+func TestUnmarshalMetricReaderWithGateOff(t *testing.T) {
+	defer setFeatureGateForTest(t, obsreportconfig.UseOtelWithSDKConfigurationForInternalTelemetryFeatureGate, false)()
+	reader := MetricReader{}
+	assert.NoError(t, reader.Unmarshal(confmap.NewFromStringMap(map[string]any{"invalid": "invalid"})))
+}
+
+func TestUnmarshalMetricReader(t *testing.T) {
+	defer setFeatureGateForTest(t, obsreportconfig.UseOtelWithSDKConfigurationForInternalTelemetryFeatureGate, true)()
 	tests := []struct {
 		name string
 		cfg  *confmap.Conf
@@ -73,12 +92,21 @@ func TestUnmarshalMetricReaders(t *testing.T) {
 		{
 			name: "invalid config",
 			cfg:  confmap.NewFromStringMap(map[string]any{"invalid": "invalid"}),
-			err:  "unsupported metric reader type \"invalid\"",
+			err:  "unsupported metric reader type [invalid]",
+		},
+		{
+			name: "invalid pull reader type with valid prometheus exporter",
+			cfg: confmap.NewFromStringMap(map[string]any{"pull/prometheus1": PullMetricReader{
+				Exporter: MetricExporter{
+					Prometheus: &Prometheus{},
+				},
+			}}),
+			err: "unsupported metric reader type [pull/prometheus1]",
 		},
 		{
 			name: "valid reader type, invalid config",
 			cfg:  confmap.NewFromStringMap(map[string]any{"pull": "garbage"}),
-			err:  "invalid pull metric reader configuration: '' expected a map, got 'string'",
+			err:  "invalid metric reader configuration",
 		},
 		{
 			name: "valid pull reader type, no exporter",
@@ -102,18 +130,10 @@ func TestUnmarshalMetricReaders(t *testing.T) {
 				},
 			}}),
 		},
-		{
-			name: "valid pull reader type with name, valid prometheus exporter",
-			cfg: confmap.NewFromStringMap(map[string]any{"pull/prometheus1": PullMetricReader{
-				Exporter: MetricExporter{
-					Prometheus: &Prometheus{},
-				},
-			}}),
-		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			reader := make(MeterProviderJsonReaders)
+			reader := MetricReader{}
 			err := reader.Unmarshal(tt.cfg)
 			if len(tt.err) > 0 {
 				assert.ErrorContains(t, err, tt.err)
diff --git a/service/telemetry_test.go b/service/telemetry_test.go
index e60b4a01278..5686ad8f01f 100644
--- a/service/telemetry_test.go
+++ b/service/telemetry_test.go
@@ -238,10 +238,12 @@ func TestTelemetryInit(t *testing.T) {
 			tel := newColTelemetry(tc.useOtel, tc.disableHighCard, tc.extendedConfig)
 			buildInfo := component.NewDefaultBuildInfo()
 			if tc.extendedConfig {
-				tc.cfg.Metrics.Readers = telemetry.MeterProviderJsonReaders{
-					"pull/prometheus": telemetry.PullMetricReader{
-						Exporter: telemetry.MetricExporter{
-							Prometheus: testutil.GetAvailableLocalAddressPrometheus(t),
+				tc.cfg.Metrics.Readers = []telemetry.MetricReader{
+					{
+						Pull: &telemetry.PullMetricReader{
+							Exporter: telemetry.MetricExporter{
+								Prometheus: testutil.GetAvailableLocalAddressPrometheus(t),
+							},
 						},
 					},
 				}

From 69ff4c31cfcd9d48fad0234be24bbe0991624c71 Mon Sep 17 00:00:00 2001
From: Alex Boten <aboten@lightstep.com>
Date: Thu, 13 Jul 2023 12:19:40 -0700
Subject: [PATCH 09/10] add issue number

Signed-off-by: Alex Boten <aboten@lightstep.com>
---
 .chloggen/codeboten_may-29-otlp-export.yaml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.chloggen/codeboten_may-29-otlp-export.yaml b/.chloggen/codeboten_may-29-otlp-export.yaml
index 19f29c21a71..c2cc4d1fef2 100755
--- a/.chloggen/codeboten_may-29-otlp-export.yaml
+++ b/.chloggen/codeboten_may-29-otlp-export.yaml
@@ -8,7 +8,7 @@ component: service
 note: Enable configuration of collector telemetry through prometheus reader
 
 # One or more tracking issues or pull requests related to the change
-issues: []
+issues: [7641]
 
 # (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.

From 8750281bbf005a51530193b1c922e1e30bb0ff89 Mon Sep 17 00:00:00 2001
From: Alex Boten <aboten@lightstep.com>
Date: Fri, 14 Jul 2023 09:23:07 -0700
Subject: [PATCH 10/10] add tests

Signed-off-by: Alex Boten <aboten@lightstep.com>
---
 service/internal/proctelemetry/config.go      |  2 +-
 service/internal/proctelemetry/config_test.go | 11 +++++++++++
 service/telemetry/config_test.go              |  3 +++
 3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/service/internal/proctelemetry/config.go b/service/internal/proctelemetry/config.go
index 67ce38fc377..27d7d8c8454 100644
--- a/service/internal/proctelemetry/config.go
+++ b/service/internal/proctelemetry/config.go
@@ -152,5 +152,5 @@ func initExporter(_ context.Context, exporter telemetry.MetricExporter, asyncErr
 	if exporter.Prometheus != nil {
 		return initPrometheusExporter(exporter.Prometheus, asyncErrorChannel)
 	}
-	return nil, nil, fmt.Errorf("no valid exporter: %v", exporter)
+	return nil, nil, fmt.Errorf("no valid exporter")
 }
diff --git a/service/internal/proctelemetry/config_test.go b/service/internal/proctelemetry/config_test.go
index 474904c8973..29127c58b1b 100644
--- a/service/internal/proctelemetry/config_test.go
+++ b/service/internal/proctelemetry/config_test.go
@@ -32,6 +32,17 @@ func TestMetricReader(t *testing.T) {
 			name: "noreader",
 			err:  errors.New("unsupported metric reader type {<nil> <nil>}"),
 		},
+		{
+			name: "pull prometheus invalid exporter",
+			reader: telemetry.MetricReader{
+				Pull: &telemetry.PullMetricReader{
+					Exporter: telemetry.MetricExporter{
+						Otlp: &telemetry.OtlpMetric{},
+					},
+				},
+			},
+			err: errors.New("no valid exporter"),
+		},
 		{
 			name: "pull/prometheus-invalid-config-no-host",
 			reader: telemetry.MetricReader{
diff --git a/service/telemetry/config_test.go b/service/telemetry/config_test.go
index c17523b1174..fa8a43f13f5 100644
--- a/service/telemetry/config_test.go
+++ b/service/telemetry/config_test.go
@@ -94,6 +94,9 @@ func TestUnmarshalMetricReader(t *testing.T) {
 			cfg:  confmap.NewFromStringMap(map[string]any{"invalid": "invalid"}),
 			err:  "unsupported metric reader type [invalid]",
 		},
+		{
+			name: "nil config, nothing to do",
+		},
 		{
 			name: "invalid pull reader type with valid prometheus exporter",
 			cfg: confmap.NewFromStringMap(map[string]any{"pull/prometheus1": PullMetricReader{