[backport main] Fix: Agent failed to upgrade from 8.4.2 to 8.5.0 BC1 …

…for MAC 12 agent using agent binary. (#1401)

[backport main] Fix: Agent failed to upgrade from 8.4.2 to 8.5.0 BC1 for MAC 12 agent using agent binary. (#1401)

dev-tools/packaging/packages.yml

@@ -1089,6 +1089,9 @@ specs:
         <<: *agent_darwin_binary_spec
         <<: *elastic_license_for_binaries
         files:
+          'data/{{.BeatName}}-{{ commit_short }}/elastic-agent':
+            template: '{{ elastic_beats_dir }}/dev-tools/packaging/templates/darwin/elastic-agent.tmpl'
+            mode: 0755
           '{{.BeatName}}{{.BinaryExt}}':
             source: data/{{.BeatName}}-{{ commit_short }}/elastic-agent.app/Contents/MacOS/{{.BeatName}}{{.BinaryExt}}
             symlink: true

dev-tools/packaging/templates/darwin/elastic-agent.tmpl

@@ -0,0 +1,11 @@
+#!/bin/sh
+# Fix up the symlink and exit
+
+set -e
+
+symlink="/Library/Elastic/Agent/elastic-agent"
+
+if test -L "$symlink"; then
+    ln -sfn "data/elastic-agent-{{ commit_short }}/elastic-agent.app/Contents/MacOS/elastic-agent" "$symlink"
+fi
+

internal/pkg/agent/application/info/state.go

@@ -5,14 +5,11 @@
 package info
 
 import (
-	"fmt"
 	"os"
 	"path/filepath"
 	"runtime"
-	"strings"
 
 	"github.com/elastic/elastic-agent/internal/pkg/agent/application/paths"
-	"github.com/elastic/elastic-agent/internal/pkg/release"
 )
 
 const (
@@ -31,30 +28,12 @@ func RunningInstalled() bool {
 	}
 	execPath, _ := os.Executable()
 	execPath, _ = filepath.Abs(execPath)
-	execName := filepath.Base(execPath)
-	execDir := filepath.Dir(execPath)
-	if IsInsideData(execDir) {
-		// executable path is being reported as being down inside of data path
-		// move up to directories to perform the comparison
-		execDir = filepath.Dir(filepath.Dir(execDir))
-		if runtime.GOOS == darwin {
-			execDir = filepath.Dir(filepath.Dir(filepath.Dir(execDir)))
-		}
-		execPath = filepath.Join(execDir, execName)
-	}
+
+	execPath = filepath.Join(paths.ExecDir(filepath.Dir(execPath)), filepath.Base(execPath))
 	for _, expected := range expectedPaths {
 		if paths.ArePathsEqual(expected, execPath) {
 			return true
 		}
 	}
 	return false
 }
-
-// IsInsideData returns true when the exePath is inside of the current Agents data path.
-func IsInsideData(exePath string) bool {
-	expectedPath := filepath.Join("data", fmt.Sprintf("elastic-agent-%s", release.ShortCommit()))
-	if runtime.GOOS == darwin {
-		expectedPath = filepath.Join(expectedPath, "elastic-agent.app", "Contents", "MacOS")
-	}
-	return strings.HasSuffix(exePath, expectedPath)
-}

internal/pkg/agent/application/paths/common.go

@@ -177,21 +177,14 @@ func SetInstall(path string) {
 // initialTop returns the initial top-level path for the binary
 //
 // When nested in top-level/data/elastic-agent-${hash}/ the result is top-level/.
-// The agent fexecutable for MacOS is wrappend in the bundle, so the path to the binary is
+// The agent executable for MacOS is wrapped in the app bundle, so the path to the binary is
 // top-level/data/elastic-agent-${hash}/elastic-agent.app/Contents/MacOS
 func initialTop() string {
-	exePath := retrieveExecutablePath()
-	if insideData(exePath) {
-		exePath = filepath.Dir(filepath.Dir(exePath))
-		if runtime.GOOS == darwin {
-			exePath = filepath.Dir(filepath.Dir(filepath.Dir(exePath)))
-		}
-	}
-	return exePath
+	return ExecDir(retrieveExecutableDir())
 }
 
 // retrieveExecutablePath returns the executing binary, even if the started binary was a symlink
-func retrieveExecutablePath() string {
+func retrieveExecutableDir() string {
 	execPath, err := os.Executable()
 	if err != nil {
 		panic(err)
@@ -203,11 +196,37 @@ func retrieveExecutablePath() string {
 	return filepath.Dir(evalPath)
 }
 
-// insideData returns true when the exePath is inside of the current Agents data path.
-func insideData(exePath string) bool {
-	expectedPath := filepath.Join("data", fmt.Sprintf("elastic-agent-%s", release.ShortCommit()))
+// isInsideData returns true when the exePath is inside of the current Agents data path.
+func isInsideData(exeDir string) bool {
+	expectedDir := binaryDir(filepath.Join("data", fmt.Sprintf("elastic-agent-%s", release.ShortCommit())))
+	return strings.HasSuffix(exeDir, expectedDir)
+}
+
+// ExecDir returns the "executable" directory which is:
+// 1. The same if the execDir is not inside of the data path
+// 2. Two levels up if the execDir inside of the data path on non-macOS platforms
+// 3. Five levels up if the execDir inside of the dataPath on macOS platform
+func ExecDir(execDir string) string {
+	if isInsideData(execDir) {
+		execDir = filepath.Dir(filepath.Dir(execDir))
+		if runtime.GOOS == darwin {
+			execDir = filepath.Dir(filepath.Dir(filepath.Dir(execDir)))
+		}
+	}
+	return execDir
+}
+
+// binaryDir returns the application binary directory
+// For macOS it appends the path inside of the app bundle
+// For other platforms it returns the same dir
+func binaryDir(baseDir string) string {
 	if runtime.GOOS == darwin {
-		expectedPath = filepath.Join(expectedPath, "elastic-agent.app", "Contents", "MacOS")
+		baseDir = filepath.Join(baseDir, "elastic-agent.app", "Contents", "MacOS")
 	}
-	return strings.HasSuffix(exePath, expectedPath)
+	return baseDir
+}
+
+// BinaryPath returns the application binary path that is concatenation of the directory and the agentName
+func BinaryPath(baseDir, agentName string) string {
+	return filepath.Join(binaryDir(baseDir), agentName)
 }

internal/pkg/agent/application/paths/common_test.go

@@ -0,0 +1,92 @@
+// Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+// or more contributor license agreements. Licensed under the Elastic License;
+// you may not use this file except in compliance with the Elastic License.
+
+package paths
+
+import (
+	"fmt"
+	"path/filepath"
+	"runtime"
+	"testing"
+
+	"github.com/elastic/elastic-agent/internal/pkg/release"
+	"github.com/google/go-cmp/cmp"
+)
+
+func validTestPath() string {
+	validPath := filepath.Join("data", fmt.Sprintf("elastic-agent-%s", release.ShortCommit()))
+	if runtime.GOOS == darwin {
+		validPath = filepath.Join(validPath, "elastic-agent.app", "Contents", "MacOS")
+	}
+	return validPath
+}
+
+func TestIsInsideData(t *testing.T) {
+	tests := []struct {
+		name    string
+		exePath string
+		res     bool
+	}{
+		{
+			name: "empty",
+		},
+		{
+			name:    "invalid",
+			exePath: "data/elastic-agent",
+		},
+		{
+			name:    "valid",
+			exePath: validTestPath(),
+			res:     true,
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			res := isInsideData(tc.exePath)
+			diff := cmp.Diff(tc.res, res)
+			if diff != "" {
+				t.Error(diff)
+			}
+		})
+	}
+}
+
+func TestExecDir(t *testing.T) {
+	base := filepath.Join(string(filepath.Separator), "Library", "Elastic", "Agent")
+	tests := []struct {
+		name    string
+		execDir string
+		resDir  string
+	}{
+		{
+			name: "empty",
+		},
+		{
+			name:    "non-data path",
+			execDir: "data/elastic-agent",
+			resDir:  "data/elastic-agent",
+		},
+		{
+			name:    "valid",
+			execDir: validTestPath(),
+			resDir:  ".",
+		},
+		{
+			name:    "valid abs",
+			execDir: filepath.Join(base, validTestPath()),
+			resDir:  base,
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			resDir := ExecDir(tc.execDir)
+			diff := cmp.Diff(tc.resDir, resDir)
+			if diff != "" {
+				t.Error(diff)
+			}
+		})
+	}
+}

internal/pkg/agent/application/upgrade/service_darwin.go

@@ -14,7 +14,6 @@ import (
 	"fmt"
 	"os"
 	"os/exec"
-	"path/filepath"
 	"regexp"
 	"strconv"
 	"strings"
@@ -50,13 +49,13 @@ func (p *darwinPidProvider) Close() {}
 
 func (p *darwinPidProvider) PID(ctx context.Context) (int, error) {
 	piders := []func(context.Context) (int, error){
-		p.piderFromCmd(ctx, "launchctl", "list", paths.ServiceName),
+		p.piderFromCmd("launchctl", "list", paths.ServiceName),
 	}
 
 	// if release is specifically built to be upgradeable (using DEV flag)
 	// we dont require to run as a service and will need sudo fallback
 	if release.Upgradeable() {
-		piders = append(piders, p.piderFromCmd(ctx, "sudo", "launchctl", "list", paths.ServiceName))
+		piders = append(piders, p.piderFromCmd("sudo", "launchctl", "list", paths.ServiceName))
 	}
 
 	var pidErrors error
@@ -72,7 +71,7 @@ func (p *darwinPidProvider) PID(ctx context.Context) (int, error) {
 	return 0, pidErrors
 }
 
-func (p *darwinPidProvider) piderFromCmd(ctx context.Context, name string, args ...string) func(context.Context) (int, error) {
+func (p *darwinPidProvider) piderFromCmd(name string, args ...string) func(context.Context) (int, error) {
 	return func(context.Context) (int, error) {
 		listCmd := exec.Command(name, args...)
 		listCmd.SysProcAttr = &syscall.SysProcAttr{
@@ -115,8 +114,8 @@ func (p *darwinPidProvider) piderFromCmd(ctx context.Context, name string, args
 }
 
 func invokeCmd(topPath string) *exec.Cmd {
-	homeExePath := filepath.Join(topPath, agentName)
-
+	// paths.BinaryPath properly derives the newPath depending on the platform. The path to the binary for macOS is inside of the app bundle.
+	homeExePath := paths.BinaryPath(topPath, agentName)
 	cmd := exec.Command(homeExePath, watcherSubcommand,
 		"--path.config", paths.Config(),
 		"--path.home", paths.Top(),

internal/pkg/agent/application/upgrade/step_relink.go

@@ -17,18 +17,25 @@ import (
 	"github.com/elastic/elastic-agent/pkg/core/logger"
 )
 
+const (
+	windows = "windows"
+	exe     = ".exe"
+)
+
 // ChangeSymlink updates symlink paths to match current version.
 func ChangeSymlink(ctx context.Context, log *logger.Logger, targetHash string) error {
 	// create symlink to elastic-agent-{hash}
 	hashedDir := fmt.Sprintf("%s-%s", agentName, targetHash)
 
 	symlinkPath := filepath.Join(paths.Top(), agentName)
-	newPath := filepath.Join(paths.Top(), "data", hashedDir, agentName)
+
+	// paths.BinaryPath properly derives the binary directory depending on the platform. The path to the binary for macOS is inside of the app bundle.
+	newPath := paths.BinaryPath(filepath.Join(paths.Top(), "data", hashedDir), agentName)
 
 	// handle windows suffixes
-	if runtime.GOOS == "windows" {
-		symlinkPath += ".exe"
-		newPath += ".exe"
+	if runtime.GOOS == windows {
+		symlinkPath += exe
+		newPath += exe
 	}
 
 	prevNewPath := prevSymlinkPath()
@@ -51,7 +58,7 @@ func prevSymlinkPath() string {
 	agentPrevName := agentName + ".prev"
 
 	// handle windows suffixes
-	if runtime.GOOS == "windows" {
+	if runtime.GOOS == windows {
 		agentPrevName = agentName + ".exe.prev"
 	}