Potentially join errors in deferred function

offen · Feb 16, 2024 · c8ca5ee · c8ca5ee
1 parent c2395c8
commit c8ca5ee
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Showing 2 changed files with 15 additions and 15 deletions.
diff --git a/cmd/backup/exec.go b/cmd/backup/exec.go
@@ -9,6 +9,7 @@ package main
 import (
 	"bytes"
 	"context"
+	"errors"
 	"fmt"
 	"io"
 	"os"
@@ -190,13 +191,12 @@ func (s *script) withLabeledCommands(step lifecyclePhase, cb func() error) func(
 	}
 	return func() (err error) {
 		if err = s.runLabeledCommands(fmt.Sprintf("docker-volume-backup.%s-pre", step)); err != nil {
-			err = fmt.Errorf("withLabeledCommands: %s: error running pre commands: %w", step, err)
+			err = fmt.Errorf("(*script).withLabeledCommands: %s: error running pre commands: %w", step, err)
 			return
 		}
 		defer func() {
-			derr := s.runLabeledCommands(fmt.Sprintf("docker-volume-backup.%s-post", step))
-			if err == nil && derr != nil {
-				err = derr
+			if derr := s.runLabeledCommands(fmt.Sprintf("docker-volume-backup.%s-post", step)); derr != nil {
+				err = errors.Join(err, fmt.Errorf("(*script).withLabeledCommands: error running %s-post commands: %w", step, derr))
 			}
 		}()
 		err = cb()

diff --git a/cmd/backup/run_script.go b/cmd/backup/run_script.go
@@ -3,7 +3,10 @@
 
 package main
 
-import "fmt"
+import (
+	"errors"
+	"fmt"
+)
 
 // runScript instantiates a new script object and orchestrates a backup run.
 // To ensure it runs mutually exclusive a global file lock is acquired before
@@ -12,7 +15,7 @@ import "fmt"
 func runScript(c *Config) (err error) {
 	defer func() {
 		if derr := recover(); derr != nil {
-			err = fmt.Errorf("runScript: unexpected panic running script: %v", err)
+			err = fmt.Errorf("runScript: unexpected panic running script: %v", derr)
 		}
 	}()
 
@@ -24,9 +27,8 @@ func runScript(c *Config) (err error) {
 		return
 	}
 	defer func() {
-		derr := unlock()
-		if err == nil && derr != nil {
-			err = fmt.Errorf("runScript: error releasing file lock: %w", derr)
+		if derr := unlock(); derr != nil {
+			err = errors.Join(err, fmt.Errorf("runScript: error releasing file lock: %w", derr))
 		}
 	}()
 
@@ -35,9 +37,8 @@ func runScript(c *Config) (err error) {
 		return fmt.Errorf("runScript: error applying env: %w", err)
 	}
 	defer func() {
-		derr := unset()
-		if err == nil && derr != nil {
-			err = fmt.Errorf("runScript: error unsetting environment variables: %w", derr)
+		if derr := unset(); derr != nil {
+			err = errors.Join(err, fmt.Errorf("runScript: error unsetting environment variables: %w", derr))
 		}
 	}()
 
@@ -54,9 +55,8 @@ func runScript(c *Config) (err error) {
 				// should happen as soon as possible (i.e. before uploading backups or
 				// similar).
 				defer func() {
-					derr := restartContainersAndServices()
-					if err == nil {
-						err = derr
+					if derr := restartContainersAndServices(); derr != nil {
+						err = errors.Join(err, fmt.Errorf("runScript: error restarting containers and services: %w", derr))
 					}
 				}()
 				if err != nil {