feat: add certificate metrics to agent for NGINXaaS

internal/collector/certificatereceiver/config.go

@@ -0,0 +1,33 @@
+// Copyright (c) F5, Inc.
+//
+// This source code is licensed under the Apache License, Version 2.0 license found in the
+// LICENSE file in the root directory of this source tree.
+package certificatereceiver
+
+import (
+	"time"
+
+	"github.com/nginx/agent/v3/internal/collector/certificatereceiver/internal/metadata"
+	"go.opentelemetry.io/collector/component"
+	"go.opentelemetry.io/collector/scraper/scraperhelper"
+)
+
+const defaultCollectInterval = 15 * time.Second
+
+type Config struct {
+	InstanceID                     string                        `mapstructure:"instance_id"`
+	CertFilePaths                  []string                      `mapstructure:"cert_file_paths"`
+	MetricsBuilderConfig           metadata.MetricsBuilderConfig `mapstructure:",squash"`
+	scraperhelper.ControllerConfig `mapstructure:",squash"`
+}
+
+//nolint:ireturn // must return default controller interface
+func createDefaultConfig() component.Config {
+	cfg := scraperhelper.NewDefaultControllerConfig()
+	cfg.CollectionInterval = defaultCollectInterval
+
+	return &Config{
+		ControllerConfig:     cfg,
+		MetricsBuilderConfig: metadata.DefaultMetricsBuilderConfig(),
+	}
+}

internal/collector/certificatereceiver/doc.go

@@ -0,0 +1,8 @@
+// Copyright (c) F5, Inc.
+//
+// This source code is licensed under the Apache License, Version 2.0 license found in the
+// LICENSE file in the root directory of this source tree.
+
+//go:generate mdatagen metadata.yaml
+
+package certificatereceiver

internal/collector/certificatereceiver/documentation.md

@@ -0,0 +1,36 @@
+[comment]: <> (Code generated by mdatagen. DO NOT EDIT.)
+
+# certificate
+
+## Default Metrics
+
+The following metrics are emitted by default. Each of them can be disabled by applying the following configuration:
+
+```yaml
+metrics:
+  <metric_name>:
+    enabled: false
+```
+
+### nginx.certificate.expiry
+
+The Unix timestamp (in seconds) at which an SSL/TLS certificate expires
+
+| Unit | Metric Type | Value Type | Stability |
+| ---- | ----------- | ---------- | --------- |
+| s | Gauge | Int | Development |
+
+#### Attributes
+
+| Name | Description | Values | Requirement Level |
+| ---- | ----------- | ------ | -------- |
+| file_path | The full file path of the certificate. | Any Str | Recommended |
+| public_key_algorithm | The public key algorithm. | Any Str | Recommended |
+| serial_number | The serial number of the certificate. | Any Str | Recommended |
+| subject.common_name | The Common Name of the certificate. | Any Str | Recommended |
+
+## Resource Attributes
+
+| Name | Description | Values | Enabled |
+| ---- | ----------- | ------ | ------- |
+| instance.id | The nginx instance id. | Any Str | true |

internal/collector/certificatereceiver/factory.go

@@ -0,0 +1,59 @@
+// Copyright (c) F5, Inc.
+//
+// This source code is licensed under the Apache License, Version 2.0 license found in the
+// LICENSE file in the root directory of this source tree.
+package certificatereceiver
+
+import (
+	"context"
+	"errors"
+
+	"github.com/nginx/agent/v3/internal/collector/certificatereceiver/internal/metadata"
+	"go.opentelemetry.io/collector/component"
+	"go.opentelemetry.io/collector/consumer"
+	"go.opentelemetry.io/collector/receiver"
+	"go.opentelemetry.io/collector/scraper"
+	"go.opentelemetry.io/collector/scraper/scraperhelper"
+)
+
+//nolint:ireturn // must return metrics receiver interface
+func NewFactory() receiver.Factory {
+	return receiver.NewFactory(
+		metadata.Type,
+		createDefaultConfig,
+		receiver.WithMetrics(createMetricsReceiver, metadata.MetricsStability))
+}
+
+//nolint:ireturn // must return metrics receiver interface
+func createMetricsReceiver(
+	ctx context.Context,
+	params receiver.Settings,
+	rConf component.Config,
+	metricsConsumer consumer.Metrics,
+) (receiver.Metrics, error) {
+	logger := params.Logger.Sugar()
+
+	logger.Info("Creating new certificate metrics receiver")
+
+	cfg, ok := rConf.(*Config)
+	if !ok {
+		return nil, errors.New("failed to cast to Config in certificate metrics receiver")
+	}
+
+	cs := newCertificateScraper(params, cfg)
+	csMetrics, csMetricsError := scraper.NewMetrics(
+		cs.Scrape,
+		scraper.WithStart(cs.Start),
+		scraper.WithShutdown(cs.Shutdown),
+	)
+	if csMetricsError != nil {
+		return nil, csMetricsError
+	}
+
+	return scraperhelper.NewMetricsController(
+		&cfg.ControllerConfig,
+		params,
+		metricsConsumer,
+		scraperhelper.AddMetricsScraper(metadata.Type, csMetrics),
+	)
+}