feat: add sentry support to capture unexpected crashes

doc: add readme entry and sentry doc

README.md

@@ -50,6 +50,7 @@ Try [a binary release](https://github.com/osrg/gobgp/releases/latest).
 - [Confederation](docs/sources/bgp-confederation.md)
 - Data Center Networking
   - [Unnumbered BGP](docs/sources/unnumbered-bgp.md)
+- [Sentry](docs/sources/sentry.md)
 
 ### Externals
 

cmd/gobgpd/main.go

@@ -31,6 +31,7 @@ import (
 	"time"
 
 	"github.com/coreos/go-systemd/v22/daemon"
+	"github.com/getsentry/sentry-go"
 	grpc_prometheus "github.com/grpc-ecosystem/go-grpc-prometheus"
 	"github.com/jessevdk/go-flags"
 	"github.com/kr/pretty"
@@ -54,39 +55,69 @@ func main() {
 	signal.Notify(sigCh, syscall.SIGTERM, syscall.SIGINT)
 
 	var opts struct {
-		ConfigFile       string `short:"f" long:"config-file" description:"specifying a config file"`
-		ConfigType       string `short:"t" long:"config-type" description:"specifying config type (toml, yaml, json)" default:"toml"`
-		ConfigAutoReload bool   `short:"a" long:"config-auto-reload" description:"activate config auto reload on changes"`
-		ConfigStrict     bool   `long:"config-strict" description:"make any config error fatal"`
-		LogLevel         string `short:"l" long:"log-level" description:"specifying log level"`
-		LogPlain         bool   `short:"p" long:"log-plain" description:"use plain format for logging (json by default)"`
-		UseSyslog        string `short:"s" long:"syslog" description:"use syslogd"`
-		Facility         string `long:"syslog-facility" description:"specify syslog facility"`
-		DisableStdlog    bool   `long:"disable-stdlog" description:"disable standard logging"`
-		CPUs             int    `long:"cpus" description:"specify the number of CPUs to be used"`
-		GrpcHosts        string `long:"api-hosts" description:"specify the hosts that gobgpd listens on" default:":50051"`
-		GracefulRestart  bool   `short:"r" long:"graceful-restart" description:"flag restart-state in graceful-restart capability"`
-		Dry              bool   `short:"d" long:"dry-run" description:"check configuration"`
-		PProfHost        string `long:"pprof-host" description:"specify the host that gobgpd listens on for pprof and metrics" default:"localhost:6060"`
-		PProfDisable     bool   `long:"pprof-disable" description:"disable pprof profiling"`
-		MetricsPath      string `long:"metrics-path" description:"specify path for prometheus metrics, empty value disables them" default:"/metrics"`
-		UseSdNotify      bool   `long:"sdnotify" description:"use sd_notify protocol"`
-		TLS              bool   `long:"tls" description:"enable TLS authentication for gRPC API"`
-		TLSCertFile      string `long:"tls-cert-file" description:"The TLS cert file"`
-		TLSKeyFile       string `long:"tls-key-file" description:"The TLS key file"`
-		TLSClientCAFile  string `long:"tls-client-ca-file" description:"Optional TLS client CA file to authenticate clients against"`
-		Version          bool   `long:"version" description:"show version number"`
+		ConfigFile        string  `short:"f" long:"config-file" description:"specifying a config file"`
+		ConfigType        string  `short:"t" long:"config-type" description:"specifying config type (toml, yaml, json)" default:"toml"`
+		ConfigAutoReload  bool    `short:"a" long:"config-auto-reload" description:"activate config auto reload on changes"`
+		ConfigStrict      bool    `long:"config-strict" description:"make any config error fatal"`
+		LogLevel          string  `short:"l" long:"log-level" description:"specifying log level"`
+		LogPlain          bool    `short:"p" long:"log-plain" description:"use plain format for logging (json by default)"`
+		UseSyslog         string  `short:"s" long:"syslog" description:"use syslogd"`
+		Facility          string  `long:"syslog-facility" description:"specify syslog facility"`
+		DisableStdlog     bool    `long:"disable-stdlog" description:"disable standard logging"`
+		CPUs              int     `long:"cpus" description:"specify the number of CPUs to be used"`
+		GrpcHosts         string  `long:"api-hosts" description:"specify the hosts that gobgpd listens on" default:":50051"`
+		GracefulRestart   bool    `short:"r" long:"graceful-restart" description:"flag restart-state in graceful-restart capability"`
+		Dry               bool    `short:"d" long:"dry-run" description:"check configuration"`
+		PProfHost         string  `long:"pprof-host" description:"specify the host that gobgpd listens on for pprof and metrics" default:"localhost:6060"`
+		PProfDisable      bool    `long:"pprof-disable" description:"disable pprof profiling"`
+		MetricsPath       string  `long:"metrics-path" description:"specify path for prometheus metrics, empty value disables them" default:"/metrics"`
+		UseSdNotify       bool    `long:"sdnotify" description:"use sd_notify protocol"`
+		TLS               bool    `long:"tls" description:"enable TLS authentication for gRPC API"`
+		TLSCertFile       string  `long:"tls-cert-file" description:"The TLS cert file"`
+		TLSKeyFile        string  `long:"tls-key-file" description:"The TLS key file"`
+		TLSClientCAFile   string  `long:"tls-client-ca-file" description:"Optional TLS client CA file to authenticate clients against"`
+		Version           bool    `long:"version" description:"show version number"`
+		SentryDSN         string  `long:"sentry-dsn" description:"Sentry DSN" default:""`
+		SentryEnvironment string  `long:"sentry-environment" description:"Sentry environment" default:"development"`
+		SentrySampleRate  float64 `long:"sentry-sample-rate" description:"Sentry traces sample rate" default:"1.0"`
+		SentryDebug       bool    `long:"sentry-debug" description:"Sentry debug mode"`
 	}
 	_, err := flags.Parse(&opts)
 	if err != nil {
-		os.Exit(1)
+		logger.Fatalf("Error parsing flags: %v", err)
 	}
 
 	if opts.Version {
 		fmt.Println("gobgpd version", version.Version())
 		os.Exit(0)
 	}
 
+	// if Sentry DSN is provided, initialize Sentry
+	// We would like to capture errors and exceptions, but not traces
+	if opts.SentryDSN != "" {
+		logger.Debugf("Initializing Sentry, Env: %s, Release: %s, SampleRate: %f, Debug: %t",
+			opts.SentryEnvironment, version.Version(), opts.SentrySampleRate, opts.SentryDebug)
+		err := sentry.Init(sentry.ClientOptions{
+			Dsn:         opts.SentryDSN,
+			SampleRate:  opts.SentrySampleRate,
+			Debug:       opts.SentryDebug,
+			Release:     version.Version(),
+			Environment: opts.SentryEnvironment,
+			// Disable tracing as it's not relevant for now
+			EnableTracing:    false,
+			TracesSampleRate: 0.0,
+		})
+		if err != nil {
+			logger.Fatalf("sentry.Init: %s", err)
+		}
+		// Flush buffered events before the program terminates.
+		defer sentry.Flush(2 * time.Second)
+
+		if opts.SentryDebug {
+			sentry.CaptureMessage("Sentry debug mode enabled on gobgpd")
+		}
+	}
+
 	if opts.CPUs == 0 {
 		runtime.GOMAXPROCS(runtime.NumCPU())
 	} else {

docs/sources/sentry.md

@@ -0,0 +1,30 @@
+# Sentry
+
+GoBGP supports Sentry for error and exception tracking.
+
+To enable Sentry, set the `--sentry-dsn` flag to your Sentry DSN.
+
+```bash
+$ gobgpd --sentry-dsn=<your-dsn>
+```
+
+In addition, you can set the `--sentry-environment` flag to your Sentry environment.
+
+```bash
+$ gobgpd --sentry-dsn=<your-dsn> --sentry-environment=<your-environment>
+```
+
+You can also set the `--sentry-sample-rate` flag to the sample rate of Sentry traces.
+
+```bash
+$ gobgpd --sentry-dsn=<your-dsn> --sentry-sample-rate=<your-sample-rate>
+```
+
+Finally, you can set the `--sentry-debug` flag to enable Sentry debug mode.
+
+```bash
+$ gobgpd --sentry-dsn=<your-dsn> --sentry-debug=true
+```
+
+When Sentry debug mode is enabled, there is a message logged to Sentry when the program starts.
+This is particularly useful to verify that Sentry is working as expected.

go.mod

@@ -8,7 +8,7 @@ require (
 	github.com/fsnotify/fsnotify v1.6.0
 	github.com/go-test/deep v1.1.0
 	github.com/google/go-cmp v0.5.9
-	github.com/google/uuid v1.3.1
+	github.com/google/uuid v1.6.0
 	github.com/grpc-ecosystem/go-grpc-prometheus v1.2.0
 	github.com/jessevdk/go-flags v1.5.0
 	github.com/k-sone/critbitgo v1.4.0
@@ -31,6 +31,7 @@ require (
 	github.com/cespare/xxhash/v2 v2.2.0 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/eapache/queue v1.1.0 // indirect
+	github.com/getsentry/sentry-go v0.30.0 // indirect
 	github.com/golang/protobuf v1.5.3 // indirect
 	github.com/hashicorp/hcl v1.0.0 // indirect
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect

go.sum

@@ -75,6 +75,8 @@ github.com/frankban/quicktest v1.14.4 h1:g2rn0vABPOOXmZUj+vbmUp0lPoXEMuhTpIluN0X
 github.com/frankban/quicktest v1.14.4/go.mod h1:4ptaffx2x8+WTWXmUCuVU6aPUX1/Mz7zb5vbUoiM6w0=
 github.com/fsnotify/fsnotify v1.6.0 h1:n+5WquG0fcWoWp6xPWfHdbskMCQaFnG6PfBrh1Ky4HY=
 github.com/fsnotify/fsnotify v1.6.0/go.mod h1:sl3t1tCWJFWoRz9R8WJCbQihKKwmorjAbSClcnxKAGw=
+github.com/getsentry/sentry-go v0.30.0 h1:lWUwDnY7sKHaVIoZ9wYqRHJ5iEmoc0pqcRqFkosKzBo=
+github.com/getsentry/sentry-go v0.30.0/go.mod h1:WU9B9/1/sHDqeV8T+3VwwbjeR5MSXs/6aqG3mqZrezA=
 github.com/go-gl/glfw v0.0.0-20190409004039-e6da0acd62b1/go.mod h1:vR7hzQXu2zJy9AVAgeJqvqgH9Q5CA+iKCZ2gyEVpxRU=
 github.com/go-gl/glfw/v3.3/glfw v0.0.0-20191125211704-12ad95a8df72/go.mod h1:tQ2UAYgL5IevRw8kRxooKSPJfGvJ9fJQFa0TUsXzTg8=
 github.com/go-gl/glfw/v3.3/glfw v0.0.0-20200222043503-6f7a984d4dc4/go.mod h1:tQ2UAYgL5IevRw8kRxooKSPJfGvJ9fJQFa0TUsXzTg8=
@@ -140,6 +142,8 @@ github.com/google/renameio v0.1.0/go.mod h1:KWCgfxg9yswjAJkECMjeO8J8rahYeXnNhOm4
 github.com/google/uuid v1.1.2/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/google/uuid v1.3.1 h1:KjJaJ9iWZ3jOFZIf1Lqf4laDRCasjl0BCmnEGxkdLb4=
 github.com/google/uuid v1.3.1/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
+github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/googleapis/gax-go/v2 v2.0.4/go.mod h1:0Wqv26UfaUD9n4G6kQubkQ+KchISgw+vpHVxEJEs9eg=
 github.com/googleapis/gax-go/v2 v2.0.5/go.mod h1:DWXyrwAJ9X0FpwwEdw+IPEYBICEFu5mhpdKc/us6bOk=
 github.com/googleapis/google-cloud-go-testing v0.0.0-20200911160855-bcd43fbb19e8/go.mod h1:dvDLG8qkwmyD9a/MJJN3XJcT3xFxOKAvTZGvuZmac9g=