Add exponential backoff to orbit enroll retries (#17368)

#16594

- [X] Changes file added for user-visible changes in `changes/` or
`orbit/changes/`.
See [Changes
files](https://fleetdm.com/docs/contributing/committing-changes#changes-files)
for more information.
- [X] Added/updated tests
- [X] Manual QA for all new/changed functionality
  - For Orbit and Fleet Desktop changes:
- [X] Manual QA must be performed in the three main OSs, macOS, Windows
and Linux.
- [X] Auto-update manual QA, from released version of component to new
version (see [tools/tuf/test](../tools/tuf/test/README.md)).

Dockerfile-desktop-linux

@@ -1,12 +1,6 @@
 FROM --platform=linux/amd64 golang:1.21.7-bullseye@sha256:447afe790df28e0bc19d782a9f776a105ce3b8417cdd21f33affc4ed6d38f9d5
 LABEL maintainer="Fleet Developers"
 
-RUN apt-get update && apt-get install -y \
-	gcc \
-	libgtk-3-dev \
-	libayatana-appindicator3-dev \
-	&& rm -rf /var/lib/apt/lists/*
-
 RUN mkdir -p /usr/src/fleet
 RUN mkdir -p /output
 

orbit/changes/16594-orbit-enroll-backoff

@@ -0,0 +1 @@
+* Add exponential backoff to orbit enroll retries.

orbit/pkg/constant/constant.go

@@ -19,10 +19,13 @@ const (
 	DesktopAppExecName = "fleet-desktop"
 	// OrbitNodeKeyFileName is the filename on disk where we write the orbit node key to
 	OrbitNodeKeyFileName = "secret-orbit-node-key.txt"
-	// OrbitEnrollMaxRetries is the max retries when doing an enroll request
-	OrbitEnrollMaxRetries = 3
-	// OrbitEnrollRetrySleep is the time duration to sleep between retries
-	OrbitEnrollRetrySleep = 5 * time.Second
+	// OrbitEnrollMaxRetries is the max number of retries when doing an enroll request.
+	// We set it to 6 to allow the retry backoff to take effect.
+	OrbitEnrollMaxRetries = 6
+	// OrbitEnrollBackoffMultiplier is the multiplier to use for backing off between enroll retries.
+	OrbitEnrollBackoffMultiplier = 2
+	// OrbitEnrollRetrySleep is the duration to sleep between enroll retries.
+	OrbitEnrollRetrySleep = 10 * time.Second
 	// OsquerydName is the name of osqueryd binary
 	// We use osqueryd as name to properly identify the process when listing
 	// running processes/tasks.

pkg/retry/retry.go

@@ -6,18 +6,26 @@ import (
 )
 
 type config struct {
-	interval    time.Duration
+	initialInterval   time.Duration
+	backoffMultiplier int
 	maxAttempts       int
 }
 
 // Option allows to configure the behavior of retry.Do
 type Option func(*config)
 
-// WithRetryInterval allows to specify a custom duration to wait
+// WithInterval allows to specify a custom duration to wait
 // between retries.
 func WithInterval(i time.Duration) Option {
 	return func(c *config) {
-		c.interval = i
+		c.initialInterval = i
+	}
+}
+
+// WithBackoffMultiplier allows to specify the backoff multiplier between retries.
+func WithBackoffMultiplier(m int) Option {
+	return func(c *config) {
+		c.backoffMultiplier = m
 	}
 }
 
@@ -37,16 +45,17 @@ func WithMaxAttempts(a int) Option {
 // seconds
 func Do(fn func() error, opts ...Option) error {
 	cfg := &config{
-		interval: 30 * time.Second,
+		initialInterval: 30 * time.Second,
 	}
 	for _, opt := range opts {
 		opt(cfg)
 	}
 
 	attempts := 0
-	ticker := time.NewTicker(cfg.interval)
+	ticker := time.NewTicker(cfg.initialInterval)
 	defer ticker.Stop()
 
+	backoff := 1
 	for {
 		attempts++
 		err := fn()
@@ -58,6 +67,12 @@ func Do(fn func() error, opts ...Option) error {
 			return err
 		}
 
+		if cfg.backoffMultiplier != 0 {
+			interval := time.Duration(backoff) * cfg.initialInterval
+			backoff *= cfg.backoffMultiplier
+			ticker.Reset(interval)
+		}
+
 		<-ticker.C
 	}
 }

pkg/retry/retry_test.go

@@ -38,4 +38,34 @@ func TestRetryDo(t *testing.T) {
 		require.NoError(t, err)
 		require.Equal(t, max, count)
 	})
+
+	t.Run("with backoff", func(t *testing.T) {
+		count := 0
+		max := 4
+		start := time.Now()
+		err := Do(func() error {
+			switch count {
+			case 0:
+				require.WithinDuration(t, start, time.Now(), 1*time.Millisecond)
+			case 1:
+				require.WithinDuration(t, start.Add(50*time.Millisecond), time.Now(), 10*time.Millisecond)
+			case 2:
+				require.WithinDuration(t, start.Add((50+100)*time.Millisecond), time.Now(), 10*time.Millisecond)
+			case 3:
+				require.WithinDuration(t, start.Add((50+100+200)*time.Millisecond), time.Now(), 10*time.Millisecond)
+			}
+			count++
+			if count != max {
+				return errTest
+			}
+			return nil
+		},
+			WithInterval(50*time.Millisecond),
+			WithBackoffMultiplier(2),
+			WithMaxAttempts(4),
+		)
+
+		require.NoError(t, err)
+		require.Equal(t, max, count)
+	})
 }

server/service/orbit_client.go

@@ -302,8 +302,12 @@ func (oc *OrbitClient) getNodeKeyOrEnroll() (string, error) {
 				return err
 			}
 		},
-		retry.WithInterval(OrbitRetryInterval()),
+		// The below configuration means the following retry intervals (exponential backoff):
+		// 10s, 20s, 40s, 80s, 160s and then return the failure (max attempts = 6)
+		// thus executing no more than ~6 enroll request failures every ~5 minutes.
+		retry.WithInterval(orbitEnrollRetryInterval()),
 		retry.WithMaxAttempts(constant.OrbitEnrollMaxRetries),
+		retry.WithBackoffMultiplier(constant.OrbitEnrollBackoffMultiplier),
 	); err != nil {
 		return "", fmt.Errorf("orbit node key enroll failed, attempts=%d", constant.OrbitEnrollMaxRetries)
 	}
@@ -402,7 +406,7 @@ func (oc *OrbitClient) setLastRecordedError(err error) {
 	oc.lastRecordedErr = fmt.Errorf("%s: %w", time.Now().UTC().Format("2006-01-02T15:04:05Z"), err)
 }
 
-func OrbitRetryInterval() time.Duration {
+func orbitEnrollRetryInterval() time.Duration {
 	interval := os.Getenv("FLEETD_ENROLL_RETRY_INTERVAL")
 	if interval != "" {
 		d, err := time.ParseDuration(interval)

tools/tuf/test/create_repository.sh

@@ -73,7 +73,9 @@ for system in $SYSTEMS; do
     # compiling a macOS-arm64 binary requires CGO and a macOS computer (for
     # Apple keychain, some tables, etc), if this is the case, compile an
     # universal binary.
-    if [ $system == "macos" ] && [ "$(uname -s)" = "Darwin" ]; then
+    #
+    # NOTE(lucas): Cross-compiling orbit for arm64 from Intel macOS currently fails (CGO error).
+    if [ $system == "macos" ] && [ "$(uname -s)" = "Darwin" ] && [ "$(uname -m)" = "arm64" ]; then
        CGO_ENABLED=1 \
        CODESIGN_IDENTITY=$CODESIGN_IDENTITY \
        ORBIT_VERSION=42 \