WIP: Implement OTel Collector Receiver interfaces

examples/testexporter/config.go

@@ -0,0 +1,30 @@
+// Copyright 2024 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package testexporter
+
+import "fmt"
+
+// Config holds the configuration for the test exporter.
+type Config struct {
+	// ExporterName is a simple test config field
+	ExporterName string `mapstructure:"exporter_name"`
+}
+
+// Validate checks if the configuration is valid.
+func (c *Config) Validate() error {
+	if c.ExporterName == "" {
+		return fmt.Errorf("exporter_name cannot be empty")
+	}
+	return nil
+}

examples/testexporter/exporter.go

@@ -0,0 +1,79 @@
+// Copyright 2024 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package testexporter
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/exporter-toolkit/otlpreceiver"
+)
+
+// Exporter is a minimal test exporter that exports a few test gauge metrics.
+type Exporter struct {
+	config     *Config
+	registry   *prometheus.Registry
+	testGauge1 prometheus.Gauge
+	testGauge2 prometheus.Gauge
+}
+
+// NewExporter creates a new test exporter instance.
+func NewExporter(config *Config) *Exporter {
+	return &Exporter{
+		config:   config,
+		registry: prometheus.NewRegistry(),
+	}
+}
+
+// Initialize sets up the exporter and returns its registry.
+func (e *Exporter) Initialize(ctx context.Context, cfg otlpreceiver.Config) (*prometheus.Registry, error) {
+	exporterCfg, ok := cfg.(*Config)
+	if !ok {
+		return nil, fmt.Errorf("invalid config type: expected *Config, got %T", cfg)
+	}
+
+	e.config = exporterCfg
+
+	fmt.Printf("Test exporter initialized with name: %s\n", e.config.ExporterName)
+
+	// Create test gauge metrics
+	e.testGauge1 = prometheus.NewGauge(prometheus.GaugeOpts{
+		Name: "test_exporter_gauge_1",
+		Help: "First test gauge metric",
+	})
+
+	e.testGauge2 = prometheus.NewGaugeVec(prometheus.GaugeOpts{
+		Name: "test_exporter_gauge_2",
+		Help: "Second test gauge metric with labels",
+	}, []string{"label1", "label2"}).WithLabelValues("value1", "value2")
+
+	// Register metrics
+	e.registry.MustRegister(e.testGauge1)
+	e.registry.MustRegister(e.testGauge2.(prometheus.Collector))
+
+	// Set initial values
+	e.testGauge1.Set(42.0)
+	e.testGauge2.Set(123.45)
+
+	fmt.Printf("Test exporter registered %d gauge metrics\n", 2)
+
+	return e.registry, nil
+}
+
+// Shutdown cleanly stops the exporter.
+func (e *Exporter) Shutdown(ctx context.Context) error {
+	fmt.Printf("Test exporter shutting down: %s\n", e.config.ExporterName)
+	return nil
+}

examples/testexporter/factory.go

@@ -0,0 +1,32 @@
+// Copyright 2024 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package testexporter
+
+import (
+	"go.opentelemetry.io/collector/component"
+	"go.opentelemetry.io/collector/receiver"
+
+	"github.com/prometheus/exporter-toolkit/otlpreceiver"
+)
+
+// NewFactory creates a factory for the test exporter receiver.
+func NewFactory() receiver.Factory {
+	receiverType := component.MustNewType("prometheus_testexporter")
+
+	return otlpreceiver.NewFactory(
+		otlpreceiver.WithType(receiverType),
+		otlpreceiver.WithInitializer(NewExporter(&Config{})),
+		otlpreceiver.WithConfigUnmarshaler(&ConfigUnmarshaler{}),
+	)
+}

examples/testexporter/go.mod

@@ -0,0 +1,48 @@
+module github.com/prometheus/exporter-toolkit/examples/testexporter
+
+go 1.24.0
+
+require (
+	github.com/prometheus/client_golang v1.23.2
+	github.com/prometheus/exporter-toolkit v0.0.0
+	go.opentelemetry.io/collector/component v1.44.0
+	go.opentelemetry.io/collector/receiver v1.44.0
+)
+
+require (
+	github.com/beorn7/perks v1.0.1 // indirect
+	github.com/cespare/xxhash/v2 v2.3.0 // indirect
+	github.com/go-logr/logr v1.4.3 // indirect
+	github.com/go-logr/stdr v1.2.2 // indirect
+	github.com/gogo/protobuf v1.3.2 // indirect
+	github.com/hashicorp/go-version v1.7.0 // indirect
+	github.com/json-iterator/go v1.1.12 // indirect
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/modern-go/reflect2 v1.0.3-0.20250322232337-35a7c28c31ee // indirect
+	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
+	github.com/prometheus/client_model v0.6.2 // indirect
+	github.com/prometheus/common v0.66.1 // indirect
+	github.com/prometheus/procfs v0.16.1 // indirect
+	go.opentelemetry.io/auto/sdk v1.1.0 // indirect
+	go.opentelemetry.io/collector/consumer v1.44.0 // indirect
+	go.opentelemetry.io/collector/featuregate v1.44.0 // indirect
+	go.opentelemetry.io/collector/internal/telemetry v0.138.0 // indirect
+	go.opentelemetry.io/collector/pdata v1.44.0 // indirect
+	go.opentelemetry.io/collector/pipeline v1.44.0 // indirect
+	go.opentelemetry.io/contrib/bridges/otelzap v0.13.0 // indirect
+	go.opentelemetry.io/otel v1.38.0 // indirect
+	go.opentelemetry.io/otel/log v0.14.0 // indirect
+	go.opentelemetry.io/otel/metric v1.38.0 // indirect
+	go.opentelemetry.io/otel/trace v1.38.0 // indirect
+	go.uber.org/multierr v1.11.0 // indirect
+	go.uber.org/zap v1.27.0 // indirect
+	go.yaml.in/yaml/v2 v2.4.3 // indirect
+	golang.org/x/net v0.45.0 // indirect
+	golang.org/x/sys v0.37.0 // indirect
+	golang.org/x/text v0.30.0 // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20250804133106-a7a43d27e69b // indirect
+	google.golang.org/grpc v1.76.0 // indirect
+	google.golang.org/protobuf v1.36.10 // indirect
+)
+
+replace github.com/prometheus/exporter-toolkit => ../..