[extension/opamp]: Add mechanism to detect whether the collector has been orphaned

.chloggen/feat_opamp-extension-monitor-ppid.yaml

@@ -0,0 +1,13 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: bug_fix
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: opampextension
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Add a new `ppid` parameter that can be used to enable orphan detection for the supervisor.
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [32189]

cmd/otelcontribcol/go.mod

@@ -648,8 +648,8 @@ require (
 	github.com/tidwall/wal v1.1.7 // indirect
 	github.com/tilinna/clock v1.1.0 // indirect
 	github.com/tinylib/msgp v1.1.9 // indirect
-	github.com/tklauser/go-sysconf v0.3.12 // indirect
-	github.com/tklauser/numcpus v0.6.1 // indirect
+	github.com/tklauser/go-sysconf v0.3.14 // indirect
+	github.com/tklauser/numcpus v0.8.0 // indirect
 	github.com/valyala/fastjson v1.6.4 // indirect
 	github.com/vincent-petithory/dataurl v1.0.0 // indirect
 	github.com/vishvananda/netlink v1.1.1-0.20201029203352-d40f9887b852 // indirect

extension/opampextension/README.md

@@ -32,6 +32,8 @@ The following settings are optional:
   - `reports_effective_config`: Whether to enable the OpAMP ReportsEffectiveConfig capability. Default is `true`.
 - `agent_description`: Setting that modifies the agent description reported to the OpAMP server.
   - `non_identifying_attributes`: A map of key value pairs that will be added to the [non-identifying attributes](https://github.com/open-telemetry/opamp-spec/blob/main/specification.md#agentdescriptionnon_identifying_attributes) reported to the OpAMP server. If an attribute collides with the default non-identifying attributes that are automatically added, the ones specified here take precedence.
+- `ppid`: An optional process ID to monitor. When this process is no longer running, the extension will emit a fatal error, causing the collector to exit. This is meant to be set by the Supervisor or some other parent process, and should not be configured manually.
+- `ppid_poll_interval`: The poll interval between check for whether `ppid` is still alive or not. Defaults to 5 seconds.
 
 ### Example
 

extension/opampextension/config.go

@@ -6,6 +6,7 @@ package opampextension // import "github.com/open-telemetry/opentelemetry-collec
 import (
 	"errors"
 	"net/url"
+	"time"
 
 	"github.com/oklog/ulid/v2"
 	"github.com/open-telemetry/opamp-go/client"
@@ -29,6 +30,15 @@ type Config struct {
 
 	// Agent descriptions contains options to modify the AgentDescription message
 	AgentDescription AgentDescription `mapstructure:"agent_description"`
+
+	// PPID is the process ID of the parent for the collector. If the PPID is specified,
+	// the extension will continuously poll for the status of the parent process, and emit a fatal error
+	// when the parent process is no longer running.
+	// If unspecified, the orphan detection logic does not run.
+	PPID int32 `mapstructure:"ppid"`
+
+	// PPIDPollInterval is the time between polling for whether PPID is running.
+	PPIDPollInterval time.Duration `mapstructure:"ppid_poll_interval"`
 }
 
 type AgentDescription struct {

extension/opampextension/config_test.go

@@ -6,6 +6,7 @@ package opampextension
 import (
 	"path/filepath"
 	"testing"
+	"time"
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
@@ -40,6 +41,7 @@ func TestUnmarshalConfig(t *testing.T) {
 			Capabilities: Capabilities{
 				ReportsEffectiveConfig: true,
 			},
+			PPIDPollInterval: 5 * time.Second,
 		}, cfg)
 }
 
@@ -60,6 +62,7 @@ func TestUnmarshalHttpConfig(t *testing.T) {
 			Capabilities: Capabilities{
 				ReportsEffectiveConfig: true,
 			},
+			PPIDPollInterval: 5 * time.Second,
 		}, cfg)
 }
 

extension/opampextension/factory.go

@@ -5,6 +5,7 @@ package opampextension // import "github.com/open-telemetry/opentelemetry-collec
 
 import (
 	"context"
+	"time"
 
 	"go.opentelemetry.io/collector/component"
 	"go.opentelemetry.io/collector/extension"
@@ -27,9 +28,10 @@ func createDefaultConfig() component.Config {
 		Capabilities: Capabilities{
 			ReportsEffectiveConfig: true,
 		},
+		PPIDPollInterval: 5 * time.Second,
 	}
 }
 
 func createExtension(_ context.Context, set extension.CreateSettings, cfg component.Config) (extension.Extension, error) {
-	return newOpampAgent(cfg.(*Config), set.Logger, set.BuildInfo, set.Resource)
+	return newOpampAgent(cfg.(*Config), set)
 }

extension/opampextension/go.mod

@@ -6,13 +6,13 @@ require (
 	github.com/google/uuid v1.6.0
 	github.com/oklog/ulid/v2 v2.1.0
 	github.com/open-telemetry/opamp-go v0.14.0
+	github.com/shirou/gopsutil/v3 v3.24.3
 	github.com/stretchr/testify v1.9.0
 	go.opentelemetry.io/collector/component v0.99.1-0.20240503164040-109173d9cf84
 	go.opentelemetry.io/collector/config/configopaque v1.6.1-0.20240503164040-109173d9cf84
 	go.opentelemetry.io/collector/config/configtls v0.99.1-0.20240503164040-109173d9cf84
 	go.opentelemetry.io/collector/confmap v0.99.1-0.20240503164040-109173d9cf84
 	go.opentelemetry.io/collector/extension v0.99.1-0.20240503164040-109173d9cf84
-	go.opentelemetry.io/collector/pdata v1.6.1-0.20240503164040-109173d9cf84
 	go.opentelemetry.io/collector/semconv v0.99.1-0.20240503164040-109173d9cf84
 	go.opentelemetry.io/otel/metric v1.26.0
 	go.opentelemetry.io/otel/trace v1.26.0
@@ -30,21 +30,29 @@ require (
 	github.com/fsnotify/fsnotify v1.7.0 // indirect
 	github.com/go-logr/logr v1.4.1 // indirect
 	github.com/go-logr/stdr v1.2.2 // indirect
+	github.com/go-ole/go-ole v1.2.6 // indirect
 	github.com/go-viper/mapstructure/v2 v2.0.0-alpha.1 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
 	github.com/gorilla/websocket v1.5.1 // indirect
 	github.com/knadh/koanf/maps v0.1.1 // indirect
 	github.com/knadh/koanf/providers/confmap v0.1.0 // indirect
 	github.com/knadh/koanf/v2 v2.1.1 // indirect
+	github.com/lufia/plan9stats v0.0.0-20211012122336-39d0f177ccd0 // indirect
 	github.com/mitchellh/copystructure v1.2.0 // indirect
 	github.com/mitchellh/reflectwalk v1.0.2 // indirect
 	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
+	github.com/power-devops/perfstat v0.0.0-20210106213030-5aafc221ea8c // indirect
 	github.com/prometheus/client_golang v1.19.0 // indirect
 	github.com/prometheus/client_model v0.6.1 // indirect
 	github.com/prometheus/common v0.53.0 // indirect
 	github.com/prometheus/procfs v0.12.0 // indirect
 	github.com/rogpeppe/go-internal v1.11.0 // indirect
+	github.com/shoenig/go-m1cpu v0.1.6 // indirect
+	github.com/tklauser/go-sysconf v0.3.14 // indirect
+	github.com/tklauser/numcpus v0.8.0 // indirect
+	github.com/yusufpapurcu/wmi v1.2.4 // indirect
 	go.opentelemetry.io/collector/config/configtelemetry v0.99.1-0.20240503164040-109173d9cf84 // indirect
+	go.opentelemetry.io/collector/pdata v1.6.1-0.20240503164040-109173d9cf84 // indirect
 	go.opentelemetry.io/otel v1.26.0 // indirect
 	go.opentelemetry.io/otel/exporters/prometheus v0.48.0 // indirect
 	go.opentelemetry.io/otel/sdk v1.26.0 // indirect

extension/opampextension/monitor_ppid.go

@@ -0,0 +1,40 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package opampextension // import "github.com/open-telemetry/opentelemetry-collector-contrib/extension/opampextension"
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/shirou/gopsutil/v3/process"
+	"go.opentelemetry.io/collector/component"
+)
+
+// monitorPPID polls for the existence of ppid.
+// If the specified ppid no longer exists, a fatal error event is reported via the passed in reportStatus function.
+func monitorPPID(ctx context.Context, interval time.Duration, ppid int32, reportStatus func(*component.StatusEvent)) {
+	for {
+		exists, err := process.PidExistsWithContext(ctx, ppid)
+		if err != nil {
+			statusErr := fmt.Errorf("collector was orphaned, failed to find process with pid %d: %w", ppid, err)
+			status := component.NewFatalErrorEvent(statusErr)
+			reportStatus(status)
+			return
+		}
+
+		if !exists {
+			statusErr := fmt.Errorf("collector was orphaned, process with pid %d does not exist", ppid)
+			status := component.NewFatalErrorEvent(statusErr)
+			reportStatus(status)
+			return
+		}
+
+		select {
+		case <-time.After(interval): // OK; Poll again to make sure PID exists
+		case <-ctx.Done():
+			return
+		}
+	}
+}