Fix WebDAV spelling, remove some inconsistencies (#143)

* Simplify logging, fix WebDAV spelling

* Define options types per package

* Move util functions that are not used cross package

* Add per file license headers

* Rename config type

internal/storage/local/local.go

@@ -1,7 +1,11 @@
+// Copyright 2022 - Offen Authors <hioffen@posteo.de>
+// SPDX-License-Identifier: MPL-2.0
+
 package local
 
 import (
 	"fmt"
+	"io"
 	"os"
 	"path"
 	"path/filepath"
@@ -16,14 +20,20 @@ type localStorage struct {
 	latestSymlink string
 }
 
+// Config allows configuration of a local storage backend.
+type Config struct {
+	ArchivePath   string
+	LatestSymlink string
+}
+
 // NewStorageBackend creates and initializes a new local storage backend.
-func NewStorageBackend(archivePath string, latestSymlink string, logFunc storage.Log) storage.Backend {
+func NewStorageBackend(opts Config, logFunc storage.Log) storage.Backend {
 	return &localStorage{
 		StorageBackend: &storage.StorageBackend{
-			DestinationPath: archivePath,
+			DestinationPath: opts.ArchivePath,
 			Log:             logFunc,
 		},
-		latestSymlink: latestSymlink,
+		latestSymlink: opts.LatestSymlink,
 	}
 }
 
@@ -34,16 +44,12 @@ func (b *localStorage) Name() string {
 
 // Copy copies the given file to the local storage backend.
 func (b *localStorage) Copy(file string) error {
-	if _, err := os.Stat(b.DestinationPath); os.IsNotExist(err) {
-		return nil
-	}
-
 	_, name := path.Split(file)
 
-	if err := utilities.CopyFile(file, path.Join(b.DestinationPath, name)); err != nil {
-		return b.Log(storage.ERROR, b.Name(), "Copy: Error copying file to local archive! %w", err)
+	if err := copyFile(file, path.Join(b.DestinationPath, name)); err != nil {
+		return fmt.Errorf("(*localStorage).Copy: Error copying file to local archive! %w", err)
 	}
-	b.Log(storage.INFO, b.Name(), "Stored copy of backup `%s` in local archive `%s`.", file, b.DestinationPath)
+	b.Log(storage.LogLevelInfo, b.Name(), "Stored copy of backup `%s` in local archive `%s`.", file, b.DestinationPath)
 
 	if b.latestSymlink != "" {
 		symlink := path.Join(b.DestinationPath, b.latestSymlink)
@@ -51,9 +57,9 @@ func (b *localStorage) Copy(file string) error {
 			os.Remove(symlink)
 		}
 		if err := os.Symlink(name, symlink); err != nil {
-			return b.Log(storage.ERROR, b.Name(), "Copy: error creating latest symlink! %w", err)
+			return fmt.Errorf("(*localStorage).Copy: error creating latest symlink! %w", err)
 		}
-		b.Log(storage.INFO, b.Name(), "Created/Updated symlink `%s` for latest backup.", b.latestSymlink)
+		b.Log(storage.LogLevelInfo, b.Name(), "Created/Updated symlink `%s` for latest backup.", b.latestSymlink)
 	}
 
 	return nil
@@ -67,8 +73,8 @@ func (b *localStorage) Prune(deadline time.Time, pruningPrefix string) (*storage
 	)
 	globMatches, err := filepath.Glob(globPattern)
 	if err != nil {
-		return nil, b.Log(storage.ERROR, b.Name(),
-			"Prune: Error looking up matching files using pattern %s! %w",
+		return nil, fmt.Errorf(
+			"(*localStorage).Prune: Error looking up matching files using pattern %s: %w",
 			globPattern,
 			err,
 		)
@@ -78,8 +84,8 @@ func (b *localStorage) Prune(deadline time.Time, pruningPrefix string) (*storage
 	for _, candidate := range globMatches {
 		fi, err := os.Lstat(candidate)
 		if err != nil {
-			return nil, b.Log(storage.ERROR, b.Name(),
-				"Prune: Error calling Lstat on file %s! %w",
+			return nil, fmt.Errorf(
+				"(*localStorage).Prune: Error calling Lstat on file %s: %w",
 				candidate,
 				err,
 			)
@@ -94,8 +100,8 @@ func (b *localStorage) Prune(deadline time.Time, pruningPrefix string) (*storage
 	for _, candidate := range candidates {
 		fi, err := os.Stat(candidate)
 		if err != nil {
-			return nil, b.Log(storage.ERROR, b.Name(),
-				"Prune: Error calling stat on file %s! %w",
+			return nil, fmt.Errorf(
+				"(*localStorage).Prune: Error calling stat on file %s! %w",
 				candidate,
 				err,
 			)
@@ -110,7 +116,7 @@ func (b *localStorage) Prune(deadline time.Time, pruningPrefix string) (*storage
 		Pruned: uint(len(matches)),
 	}
 
-	b.DoPrune(b.Name(), len(matches), len(candidates), "local backup(s)", func() error {
+	if err := b.DoPrune(b.Name(), len(matches), len(candidates), "local backup(s)", func() error {
 		var removeErrors []error
 		for _, match := range matches {
 			if err := os.Remove(match); err != nil {
@@ -118,14 +124,37 @@ func (b *localStorage) Prune(deadline time.Time, pruningPrefix string) (*storage
 			}
 		}
 		if len(removeErrors) != 0 {
-			return b.Log(storage.ERROR, b.Name(),
-				"Prune: %d error(s) deleting local files, starting with: %w",
+			return fmt.Errorf(
+				"(*localStorage).Prune: %d error(s) deleting local files, starting with: %w",
 				len(removeErrors),
 				utilities.Join(removeErrors...),
 			)
 		}
 		return nil
-	})
+	}); err != nil {
+		return stats, err
+	}
 
 	return stats, nil
 }
+
+// copy creates a copy of the file located at `dst` at `src`.
+func copyFile(src, dst string) error {
+	in, err := os.Open(src)
+	if err != nil {
+		return err
+	}
+	defer in.Close()
+
+	out, err := os.Create(dst)
+	if err != nil {
+		return err
+	}
+
+	_, err = io.Copy(out, in)
+	if err != nil {
+		out.Close()
+		return err
+	}
+	return out.Close()
+}

internal/storage/s3/s3.go

@@ -1,8 +1,12 @@
+// Copyright 2022 - Offen Authors <hioffen@posteo.de>
+// SPDX-License-Identifier: MPL-2.0
+
 package s3
 
 import (
 	"context"
 	"errors"
+	"fmt"
 	"path"
 	"path/filepath"
 	"time"
@@ -20,54 +24,66 @@ type s3Storage struct {
 	storageClass string
 }
 
+// Config contains values that define the configuration of a S3 backend.
+type Config struct {
+	Endpoint         string
+	AccessKeyID      string
+	SecretAccessKey  string
+	IamRoleEndpoint  string
+	EndpointProto    string
+	EndpointInsecure bool
+	RemotePath       string
+	BucketName       string
+	StorageClass     string
+}
+
 // NewStorageBackend creates and initializes a new S3/Minio storage backend.
-func NewStorageBackend(endpoint string, accessKeyId string, secretAccessKey string, iamRoleEndpoint string, endpointProto string, endpointInsecure bool,
-	remotePath string, bucket string, storageClass string, logFunc storage.Log) (storage.Backend, error) {
+func NewStorageBackend(opts Config, logFunc storage.Log) (storage.Backend, error) {
 
 	var creds *credentials.Credentials
-	if accessKeyId != "" && secretAccessKey != "" {
+	if opts.AccessKeyID != "" && opts.SecretAccessKey != "" {
 		creds = credentials.NewStaticV4(
-			accessKeyId,
-			secretAccessKey,
+			opts.AccessKeyID,
+			opts.SecretAccessKey,
 			"",
 		)
-	} else if iamRoleEndpoint != "" {
-		creds = credentials.NewIAM(iamRoleEndpoint)
+	} else if opts.IamRoleEndpoint != "" {
+		creds = credentials.NewIAM(opts.IamRoleEndpoint)
 	} else {
-		return nil, errors.New("newScript: AWS_S3_BUCKET_NAME is defined, but no credentials were provided")
+		return nil, errors.New("NewStorageBackend: AWS_S3_BUCKET_NAME is defined, but no credentials were provided")
 	}
 
 	options := minio.Options{
 		Creds:  creds,
-		Secure: endpointProto == "https",
+		Secure: opts.EndpointProto == "https",
 	}
 
-	if endpointInsecure {
+	if opts.EndpointInsecure {
 		if !options.Secure {
-			return nil, errors.New("newScript: AWS_ENDPOINT_INSECURE = true is only meaningful for https")
+			return nil, errors.New("NewStorageBackend: AWS_ENDPOINT_INSECURE = true is only meaningful for https")
 		}
 
 		transport, err := minio.DefaultTransport(true)
 		if err != nil {
-			return nil, logFunc(storage.ERROR, "S3", "NewScript: failed to create default minio transport")
+			return nil, fmt.Errorf("NewStorageBackend: failed to create default minio transport")
 		}
 		transport.TLSClientConfig.InsecureSkipVerify = true
 		options.Transport = transport
 	}
 
-	mc, err := minio.New(endpoint, &options)
+	mc, err := minio.New(opts.Endpoint, &options)
 	if err != nil {
-		return nil, logFunc(storage.ERROR, "S3", "NewScript: error setting up minio client: %w", err)
+		return nil, fmt.Errorf("NewStorageBackend: error setting up minio client: %w", err)
 	}
 
 	return &s3Storage{
 		StorageBackend: &storage.StorageBackend{
-			DestinationPath: remotePath,
+			DestinationPath: opts.RemotePath,
 			Log:             logFunc,
 		},
 		client:       mc,
-		bucket:       bucket,
-		storageClass: storageClass,
+		bucket:       opts.BucketName,
+		storageClass: opts.StorageClass,
 	}, nil
 }
 
@@ -85,9 +101,9 @@ func (b *s3Storage) Copy(file string) error {
 		StorageClass: b.storageClass,
 	}); err != nil {
 		errResp := minio.ToErrorResponse(err)
-		return b.Log(storage.ERROR, b.Name(), "Copy: error uploading backup to remote storage: [Message]: '%s', [Code]: %s, [StatusCode]: %d", errResp.Message, errResp.Code, errResp.StatusCode)
+		return fmt.Errorf("(*s3Storage).Copy: error uploading backup to remote storage: [Message]: '%s', [Code]: %s, [StatusCode]: %d", errResp.Message, errResp.Code, errResp.StatusCode)
 	}
-	b.Log(storage.INFO, b.Name(), "Uploaded a copy of backup `%s` to bucket `%s`.", file, b.bucket)
+	b.Log(storage.LogLevelInfo, b.Name(), "Uploaded a copy of backup `%s` to bucket `%s`.", file, b.bucket)
 
 	return nil
 }
@@ -105,8 +121,8 @@ func (b *s3Storage) Prune(deadline time.Time, pruningPrefix string) (*storage.Pr
 	for candidate := range candidates {
 		lenCandidates++
 		if candidate.Err != nil {
-			return nil, b.Log(storage.ERROR, b.Name(),
-				"Prune: Error looking up candidates from remote storage! %w",
+			return nil, fmt.Errorf(
+				"(*s3Storage).Prune: Error looking up candidates from remote storage! %w",
 				candidate.Err,
 			)
 		}
@@ -120,7 +136,7 @@ func (b *s3Storage) Prune(deadline time.Time, pruningPrefix string) (*storage.Pr
 		Pruned: uint(len(matches)),
 	}
 
-	b.DoPrune(b.Name(), len(matches), lenCandidates, "remote backup(s)", func() error {
+	if err := b.DoPrune(b.Name(), len(matches), lenCandidates, "remote backup(s)", func() error {
 		objectsCh := make(chan minio.ObjectInfo)
 		go func() {
 			for _, match := range matches {
@@ -139,7 +155,9 @@ func (b *s3Storage) Prune(deadline time.Time, pruningPrefix string) (*storage.Pr
 			return utilities.Join(removeErrors...)
 		}
 		return nil
-	})
+	}); err != nil {
+		return stats, err
+	}
 
 	return stats, nil
 }

internal/storage/ssh/ssh.go

@@ -1,3 +1,6 @@
+// Copyright 2022 - Offen Authors <hioffen@posteo.de>
+// SPDX-License-Identifier: MPL-2.0
+
 package ssh
 
 import (
@@ -23,47 +26,56 @@ type sshStorage struct {
 	hostName   string
 }
 
-// NewStorageBackend creates and initializes a new SSH storage backend.
-func NewStorageBackend(hostName string, port string, user string, password string, identityFile string, identityPassphrase string, remotePath string,
-	logFunc storage.Log) (storage.Backend, error) {
+// Config allows to configure a SSH backend.
+type Config struct {
+	HostName           string
+	Port               string
+	User               string
+	Password           string
+	IdentityFile       string
+	IdentityPassphrase string
+	RemotePath         string
+}
 
+// NewStorageBackend creates and initializes a new SSH storage backend.
+func NewStorageBackend(opts Config, logFunc storage.Log) (storage.Backend, error) {
 	var authMethods []ssh.AuthMethod
 
-	if password != "" {
-		authMethods = append(authMethods, ssh.Password(password))
+	if opts.Password != "" {
+		authMethods = append(authMethods, ssh.Password(opts.Password))
 	}
 
-	if _, err := os.Stat(identityFile); err == nil {
-		key, err := ioutil.ReadFile(identityFile)
+	if _, err := os.Stat(opts.IdentityFile); err == nil {
+		key, err := ioutil.ReadFile(opts.IdentityFile)
 		if err != nil {
-			return nil, errors.New("newScript: error reading the private key")
+			return nil, errors.New("NewStorageBackend: error reading the private key")
 		}
 
 		var signer ssh.Signer
-		if identityPassphrase != "" {
-			signer, err = ssh.ParsePrivateKeyWithPassphrase(key, []byte(identityPassphrase))
+		if opts.IdentityPassphrase != "" {
+			signer, err = ssh.ParsePrivateKeyWithPassphrase(key, []byte(opts.IdentityPassphrase))
 			if err != nil {
-				return nil, errors.New("newScript: error parsing the encrypted private key")
+				return nil, errors.New("NewStorageBackend: error parsing the encrypted private key")
 			}
 			authMethods = append(authMethods, ssh.PublicKeys(signer))
 		} else {
 			signer, err = ssh.ParsePrivateKey(key)
 			if err != nil {
-				return nil, errors.New("newScript: error parsing the private key")
+				return nil, errors.New("NewStorageBackend: error parsing the private key")
 			}
 			authMethods = append(authMethods, ssh.PublicKeys(signer))
 		}
 	}
 
 	sshClientConfig := &ssh.ClientConfig{
-		User:            user,
+		User:            opts.User,
 		Auth:            authMethods,
 		HostKeyCallback: ssh.InsecureIgnoreHostKey(),
 	}
-	sshClient, err := ssh.Dial("tcp", fmt.Sprintf("%s:%s", hostName, port), sshClientConfig)
+	sshClient, err := ssh.Dial("tcp", fmt.Sprintf("%s:%s", opts.HostName, opts.Port), sshClientConfig)
 
 	if err != nil {
-		return nil, logFunc(storage.ERROR, "SSH", "NewScript: Error creating ssh client! %w", err)
+		return nil, fmt.Errorf("NewStorageBackend: Error creating ssh client: %w", err)
 	}
 	_, _, err = sshClient.SendRequest("keepalive", false, nil)
 	if err != nil {
@@ -72,17 +84,17 @@ func NewStorageBackend(hostName string, port string, user string, password strin
 
 	sftpClient, err := sftp.NewClient(sshClient)
 	if err != nil {
-		return nil, logFunc(storage.ERROR, "SSH", "NewScript: error creating sftp client! %w", err)
+		return nil, fmt.Errorf("NewStorageBackend: error creating sftp client: %w", err)
 	}
 
 	return &sshStorage{
 		StorageBackend: &storage.StorageBackend{
-			DestinationPath: remotePath,
+			DestinationPath: opts.RemotePath,
 			Log:             logFunc,
 		},
 		client:     sshClient,
 		sftpClient: sftpClient,
-		hostName:   hostName,
+		hostName:   opts.HostName,
 	}, nil
 }
 
@@ -96,13 +108,13 @@ func (b *sshStorage) Copy(file string) error {
 	source, err := os.Open(file)
 	_, name := path.Split(file)
 	if err != nil {
-		return b.Log(storage.ERROR, b.Name(), "Copy: Error reading the file to be uploaded! %w", err)
+		return fmt.Errorf("(*sshStorage).Copy: Error reading the file to be uploaded! %w", err)
 	}
 	defer source.Close()
 
 	destination, err := b.sftpClient.Create(filepath.Join(b.DestinationPath, name))
 	if err != nil {
-		return b.Log(storage.ERROR, b.Name(), "Copy: Error creating file on SSH storage! %w", err)
+		return fmt.Errorf("(*sshStorage).Copy: Error creating file on SSH storage! %w", err)
 	}
 	defer destination.Close()
 
@@ -112,31 +124,31 @@ func (b *sshStorage) Copy(file string) error {
 		if err == io.EOF {
 			tot, err := destination.Write(chunk[:num])
 			if err != nil {
-				return b.Log(storage.ERROR, b.Name(), "Copy: Error uploading the file to SSH storage! %w", err)
+				return fmt.Errorf("(*sshStorage).Copy: Error uploading the file to SSH storage! %w", err)
 			}
 
 			if tot != len(chunk[:num]) {
-				return b.Log(storage.ERROR, b.Name(), "sshClient: failed to write stream")
+				return errors.New("(*sshStorage).Copy: failed to write stream")
 			}
 
 			break
 		}
 
 		if err != nil {
-			return b.Log(storage.ERROR, b.Name(), "Copy: Error uploading the file to SSH storage! %w", err)
+			return fmt.Errorf("(*sshStorage).Copy: Error uploading the file to SSH storage! %w", err)
 		}
 
 		tot, err := destination.Write(chunk[:num])
 		if err != nil {
-			return b.Log(storage.ERROR, b.Name(), "Copy: Error uploading the file to SSH storage! %w", err)
+			return fmt.Errorf("(*sshStorage).Copy: Error uploading the file to SSH storage! %w", err)
 		}
 
 		if tot != len(chunk[:num]) {
-			return b.Log(storage.ERROR, b.Name(), "sshClient: failed to write stream")
+			return fmt.Errorf("(*sshStorage).Copy: failed to write stream")
 		}
 	}
 
-	b.Log(storage.INFO, b.Name(), "Uploaded a copy of backup `%s` to SSH storage '%s' at path '%s'.", file, b.hostName, b.DestinationPath)
+	b.Log(storage.LogLevelInfo, b.Name(), "Uploaded a copy of backup `%s` to SSH storage '%s' at path '%s'.", file, b.hostName, b.DestinationPath)
 
 	return nil
 }
@@ -145,7 +157,7 @@ func (b *sshStorage) Copy(file string) error {
 func (b *sshStorage) Prune(deadline time.Time, pruningPrefix string) (*storage.PruneStats, error) {
 	candidates, err := b.sftpClient.ReadDir(b.DestinationPath)
 	if err != nil {
-		return nil, b.Log(storage.ERROR, b.Name(), "Prune: Error reading directory from SSH storage! %w", err)
+		return nil, fmt.Errorf("(*sshStorage).Prune: Error reading directory from SSH storage! %w", err)
 	}
 
 	var matches []string
@@ -163,14 +175,16 @@ func (b *sshStorage) Prune(deadline time.Time, pruningPrefix string) (*storage.P
 		Pruned: uint(len(matches)),
 	}
 
-	b.DoPrune(b.Name(), len(matches), len(candidates), "SSH backup(s)", func() error {
+	if err := b.DoPrune(b.Name(), len(matches), len(candidates), "SSH backup(s)", func() error {
 		for _, match := range matches {
 			if err := b.sftpClient.Remove(filepath.Join(b.DestinationPath, match)); err != nil {
-				return b.Log(storage.ERROR, b.Name(), "Prune: Error removing file from SSH storage! %w", err)
+				return fmt.Errorf("(*sshStorage).Prune: Error removing file from SSH storage! %w", err)
 			}
 		}
 		return nil
-	})
+	}); err != nil {
+		return stats, err
+	}
 
 	return stats, nil
 }

internal/storage/storage.go

@@ -1,3 +1,6 @@
+// Copyright 2022 - Offen Authors <hioffen@posteo.de>
+// SPDX-License-Identifier: MPL-2.0
+
 package storage
 
 import (
@@ -18,15 +21,15 @@ type StorageBackend struct {
 	Log             Log
 }
 
-type LogType string
+type LogLevel int
 
 const (
-	INFO    LogType = "INFO"
-	WARNING LogType = "WARNING"
-	ERROR   LogType = "ERROR"
+	LogLevelInfo LogLevel = iota
+	LogLevelWarning
+	LogLevelError
 )
 
-type Log func(logType LogType, context string, msg string, params ...interface{}) error
+type Log func(logType LogLevel, context string, msg string, params ...interface{})
 
 // PruneStats is a wrapper struct for returning stats after pruning
 type PruneStats struct {
@@ -41,7 +44,7 @@ func (b *StorageBackend) DoPrune(context string, lenMatches, lenCandidates int,
 		if err := doRemoveFiles(); err != nil {
 			return err
 		}
-		b.Log(INFO, context,
+		b.Log(LogLevelInfo, context,
 			"Pruned %d out of %d %s as their age exceeded the configured retention period of %d days.",
 			lenMatches,
 			lenCandidates,
@@ -49,10 +52,10 @@ func (b *StorageBackend) DoPrune(context string, lenMatches, lenCandidates int,
 			b.RetentionDays,
 		)
 	} else if lenMatches != 0 && lenMatches == lenCandidates {
-		b.Log(WARNING, context, "The current configuration would delete all %d existing %s.", lenMatches, description)
-		b.Log(WARNING, context, "Refusing to do so, please check your configuration.")
+		b.Log(LogLevelWarning, context, "The current configuration would delete all %d existing %s.", lenMatches, description)
+		b.Log(LogLevelWarning, context, "Refusing to do so, please check your configuration.")
 	} else {
-		b.Log(INFO, context, "None of %d existing %s were pruned.", lenCandidates, description)
+		b.Log(LogLevelInfo, context, "None of %d existing %s were pruned.", lenCandidates, description)
 	}
 	return nil
 }

internal/storage/webdav/webdav.go

@@ -1,7 +1,11 @@
+// Copyright 2022 - Offen Authors <hioffen@posteo.de>
+// SPDX-License-Identifier: MPL-2.0
+
 package webdav
 
 import (
 	"errors"
+	"fmt"
 	"io/fs"
 	"net/http"
 	"os"
@@ -20,28 +24,36 @@ type webDavStorage struct {
 	url    string
 }
 
+// Config allows to configure a WebDAV storage backend.
+type Config struct {
+	URL         string
+	RemotePath  string
+	Username    string
+	Password    string
+	URLInsecure bool
+}
+
 // NewStorageBackend creates and initializes a new WebDav storage backend.
-func NewStorageBackend(url string, remotePath string, username string, password string, urlInsecure bool,
-	logFunc storage.Log) (storage.Backend, error) {
+func NewStorageBackend(opts Config, logFunc storage.Log) (storage.Backend, error) {
 
-	if username == "" || password == "" {
-		return nil, errors.New("newScript: WEBDAV_URL is defined, but no credentials were provided")
+	if opts.Username == "" || opts.Password == "" {
+		return nil, errors.New("NewStorageBackend: WEBDAV_URL is defined, but no credentials were provided")
 	} else {
-		webdavClient := gowebdav.NewClient(url, username, password)
+		webdavClient := gowebdav.NewClient(opts.URL, opts.Username, opts.Password)
 
-		if urlInsecure {
+		if opts.URLInsecure {
 			defaultTransport, ok := http.DefaultTransport.(*http.Transport)
 			if !ok {
-				return nil, errors.New("newScript: unexpected error when asserting type for http.DefaultTransport")
+				return nil, errors.New("NewStorageBackend: unexpected error when asserting type for http.DefaultTransport")
 			}
 			webdavTransport := defaultTransport.Clone()
-			webdavTransport.TLSClientConfig.InsecureSkipVerify = urlInsecure
+			webdavTransport.TLSClientConfig.InsecureSkipVerify = opts.URLInsecure
 			webdavClient.SetTransport(webdavTransport)
 		}
 
 		return &webDavStorage{
 			StorageBackend: &storage.StorageBackend{
-				DestinationPath: remotePath,
+				DestinationPath: opts.RemotePath,
 				Log:             logFunc,
 			},
 			client: webdavClient,
@@ -51,7 +63,7 @@ func NewStorageBackend(url string, remotePath string, username string, password
 
 // Name returns the name of the storage backend
 func (b *webDavStorage) Name() string {
-	return "WebDav"
+	return "WebDAV"
 }
 
 // Copy copies the given file to the WebDav storage backend.
@@ -59,15 +71,15 @@ func (b *webDavStorage) Copy(file string) error {
 	bytes, err := os.ReadFile(file)
 	_, name := path.Split(file)
 	if err != nil {
-		return b.Log(storage.ERROR, b.Name(), "Copy: Error reading the file to be uploaded! %w", err)
+		return fmt.Errorf("(*webDavStorage).Copy: Error reading the file to be uploaded! %w", err)
 	}
 	if err := b.client.MkdirAll(b.DestinationPath, 0644); err != nil {
-		return b.Log(storage.ERROR, b.Name(), "Copy: Error creating directory '%s' on WebDAV server! %w", b.DestinationPath, err)
+		return fmt.Errorf("(*webDavStorage).Copy: Error creating directory '%s' on WebDAV server! %w", b.DestinationPath, err)
 	}
 	if err := b.client.Write(filepath.Join(b.DestinationPath, name), bytes, 0644); err != nil {
-		return b.Log(storage.ERROR, b.Name(), "Copy: Error uploading the file to WebDAV server! %w", err)
+		return fmt.Errorf("(*webDavStorage).Copy: Error uploading the file to WebDAV server! %w", err)
 	}
-	b.Log(storage.INFO, b.Name(), "Uploaded a copy of backup `%s` to WebDAV-URL '%s' at path '%s'.", file, b.url, b.DestinationPath)
+	b.Log(storage.LogLevelInfo, b.Name(), "Uploaded a copy of backup `%s` to WebDAV-URL '%s' at path '%s'.", file, b.url, b.DestinationPath)
 
 	return nil
 }
@@ -76,7 +88,7 @@ func (b *webDavStorage) Copy(file string) error {
 func (b *webDavStorage) Prune(deadline time.Time, pruningPrefix string) (*storage.PruneStats, error) {
 	candidates, err := b.client.ReadDir(b.DestinationPath)
 	if err != nil {
-		return nil, b.Log(storage.ERROR, b.Name(), "Prune: Error looking up candidates from remote storage! %w", err)
+		return nil, fmt.Errorf("(*webDavStorage).Prune: Error looking up candidates from remote storage! %w", err)
 	}
 	var matches []fs.FileInfo
 	var lenCandidates int
@@ -95,14 +107,16 @@ func (b *webDavStorage) Prune(deadline time.Time, pruningPrefix string) (*storag
 		Pruned: uint(len(matches)),
 	}
 
-	b.DoPrune(b.Name(), len(matches), lenCandidates, "WebDAV backup(s)", func() error {
+	if err := b.DoPrune(b.Name(), len(matches), lenCandidates, "WebDAV backup(s)", func() error {
 		for _, match := range matches {
 			if err := b.client.Remove(filepath.Join(b.DestinationPath, match.Name())); err != nil {
-				return b.Log(storage.ERROR, b.Name(), "Prune: Error removing file from WebDAV storage! %w", err)
+				return fmt.Errorf("(*webDavStorage).Prune: Error removing file from WebDAV storage! %w", err)
 			}
 		}
 		return nil
-	})
+	}); err != nil {
+		return stats, err
+	}
 
 	return stats, nil
 }

internal/utilities/util.go

@@ -4,38 +4,11 @@
 package utilities
 
 import (
-	"bytes"
 	"errors"
-	"fmt"
-	"io"
-	"os"
 	"strings"
 )
 
-var Noop = func() error { return nil }
-
-// copy creates a copy of the file located at `dst` at `src`.
-func CopyFile(src, dst string) error {
-	in, err := os.Open(src)
-	if err != nil {
-		return err
-	}
-	defer in.Close()
-
-	out, err := os.Create(dst)
-	if err != nil {
-		return err
-	}
-
-	_, err = io.Copy(out, in)
-	if err != nil {
-		out.Close()
-		return err
-	}
-	return out.Close()
-}
-
-// join takes a list of errors and joins them into a single error
+// Join takes a list of errors and joins them into a single error
 func Join(errs ...error) error {
 	if len(errs) == 1 {
 		return errs[0]
@@ -49,42 +22,3 @@ func Join(errs ...error) error {
 	}
 	return errors.New("[" + strings.Join(msgs, ", ") + "]")
 }
-
-// remove removes the given file or directory from disk.
-func Remove(location string) error {
-	fi, err := os.Lstat(location)
-	if err != nil {
-		if os.IsNotExist(err) {
-			return nil
-		}
-		return fmt.Errorf("remove: error checking for existence of `%s`: %w", location, err)
-	}
-	if fi.IsDir() {
-		err = os.RemoveAll(location)
-	} else {
-		err = os.Remove(location)
-	}
-	if err != nil {
-		return fmt.Errorf("remove: error removing `%s`: %w", location, err)
-	}
-	return nil
-}
-
-// buffer takes an io.Writer and returns a wrapped version of the
-// writer that writes to both the original target as well as the returned buffer
-func Buffer(w io.Writer) (io.Writer, *bytes.Buffer) {
-	buffering := &bufferingWriter{buf: bytes.Buffer{}, writer: w}
-	return buffering, &buffering.buf
-}
-
-type bufferingWriter struct {
-	buf    bytes.Buffer
-	writer io.Writer
-}
-
-func (b *bufferingWriter) Write(p []byte) (n int, err error) {
-	if n, err := b.buf.Write(p); err != nil {
-		return n, fmt.Errorf("bufferingWriter: error writing to buffer: %w", err)
-	}
-	return b.writer.Write(p)
-}