Add errorlint linter

.golangci.yml

@@ -7,6 +7,7 @@ linters:
     - depguard
     - dogsled
     - errcheck
+    - errorlint
     - exportloopref
     - gocyclo
     - goprintffuncname

core/agents/lastfm/agent.go

@@ -2,6 +2,7 @@ package lastfm
 
 import (
 	"context"
+	"errors"
 	"net/http"
 
 	"github.com/navidrome/navidrome/conf"
@@ -118,7 +119,9 @@ func (l *lastfmAgent) GetTopSongs(ctx context.Context, id, artistName, mbid stri
 
 func (l *lastfmAgent) callArtistGetInfo(ctx context.Context, name string, mbid string) (*Artist, error) {
 	a, err := l.client.ArtistGetInfo(ctx, name, mbid)
-	lfErr, isLastFMError := err.(*lastFMError)
+	var lfErr *lastFMError
+	isLastFMError := errors.As(err, &lfErr)
+
 	if mbid != "" && ((err == nil && a.Name == "[unknown]") || (isLastFMError && lfErr.Code == 6)) {
 		log.Warn(ctx, "LastFM/artist.getInfo could not find artist by mbid, trying again", "artist", name, "mbid", mbid)
 		return l.callArtistGetInfo(ctx, name, "")
@@ -133,7 +136,8 @@ func (l *lastfmAgent) callArtistGetInfo(ctx context.Context, name string, mbid s
 
 func (l *lastfmAgent) callArtistGetSimilar(ctx context.Context, name string, mbid string, limit int) ([]Artist, error) {
 	s, err := l.client.ArtistGetSimilar(ctx, name, mbid, limit)
-	lfErr, isLastFMError := err.(*lastFMError)
+	var lfErr *lastFMError
+	isLastFMError := errors.As(err, &lfErr)
 	if mbid != "" && ((err == nil && s.Attr.Artist == "[unknown]") || (isLastFMError && lfErr.Code == 6)) {
 		log.Warn(ctx, "LastFM/artist.getSimilar could not find artist by mbid, trying again", "artist", name, "mbid", mbid)
 		return l.callArtistGetSimilar(ctx, name, "", limit)
@@ -147,7 +151,8 @@ func (l *lastfmAgent) callArtistGetSimilar(ctx context.Context, name string, mbi
 
 func (l *lastfmAgent) callArtistGetTopTracks(ctx context.Context, artistName, mbid string, count int) ([]Track, error) {
 	t, err := l.client.ArtistGetTopTracks(ctx, artistName, mbid, count)
-	lfErr, isLastFMError := err.(*lastFMError)
+	var lfErr *lastFMError
+	isLastFMError := errors.As(err, &lfErr)
 	if mbid != "" && ((err == nil && t.Attr.Artist == "[unknown]") || (isLastFMError && lfErr.Code == 6)) {
 		log.Warn(ctx, "LastFM/artist.getTopTracks could not find artist by mbid, trying again", "artist", artistName, "mbid", mbid)
 		return l.callArtistGetTopTracks(ctx, artistName, "", count)
@@ -204,7 +209,8 @@ func (l *lastfmAgent) Scrobble(ctx context.Context, userId string, s scrobbler.S
 	if err == nil {
 		return nil
 	}
-	lfErr, isLastFMError := err.(*lastFMError)
+	var lfErr *lastFMError
+	isLastFMError := errors.As(err, &lfErr)
 	if !isLastFMError {
 		log.Warn(ctx, "Last.fm client.scrobble returned error", "track", s.Title, err)
 		return scrobbler.ErrRetryLater

core/agents/listenbrainz/agent.go

@@ -2,6 +2,7 @@ package listenbrainz
 
 import (
 	"context"
+	"errors"
 	"net/http"
 
 	"github.com/navidrome/navidrome/conf"
@@ -88,7 +89,8 @@ func (l *listenBrainzAgent) Scrobble(ctx context.Context, userId string, s scrob
 	if err == nil {
 		return nil
 	}
-	lbErr, isListenBrainzError := err.(*listenBrainzError)
+	var lbErr *listenBrainzError
+	isListenBrainzError := errors.As(err, &lbErr)
 	if !isListenBrainzError {
 		log.Warn(ctx, "ListenBrainz Scrobble returned HTTP error", "track", s.Title, err)
 		return scrobbler.ErrRetryLater

persistence/user_repository_test.go

@@ -95,7 +95,8 @@ var _ = Describe("UserRepository", func() {
 				user := *loggedUser
 				user.NewPassword = "new"
 				err := validatePasswordChange(&user, loggedUser)
-				verr := err.(*rest.ValidationError)
+				var verr *rest.ValidationError
+				errors.As(err, &verr)
 				Expect(verr.Errors).To(HaveLen(1))
 				Expect(verr.Errors).To(HaveKeyWithValue("currentPassword", "ra.validation.required"))
 			})
@@ -104,7 +105,8 @@ var _ = Describe("UserRepository", func() {
 				user := *loggedUser
 				user.CurrentPassword = "abc123"
 				err := validatePasswordChange(&user, loggedUser)
-				verr := err.(*rest.ValidationError)
+				var verr *rest.ValidationError
+				errors.As(err, &verr)
 				Expect(verr.Errors).To(HaveLen(1))
 				Expect(verr.Errors).To(HaveKeyWithValue("password", "ra.validation.required"))
 			})
@@ -114,7 +116,8 @@ var _ = Describe("UserRepository", func() {
 				user.CurrentPassword = "current"
 				user.NewPassword = "new"
 				err := validatePasswordChange(&user, loggedUser)
-				verr := err.(*rest.ValidationError)
+				var verr *rest.ValidationError
+				errors.As(err, &verr)
 				Expect(verr.Errors).To(HaveLen(1))
 				Expect(verr.Errors).To(HaveKeyWithValue("currentPassword", "ra.validation.passwordDoesNotMatch"))
 			})
@@ -136,7 +139,8 @@ var _ = Describe("UserRepository", func() {
 				user := *loggedUser
 				user.NewPassword = "new"
 				err := validatePasswordChange(&user, loggedUser)
-				verr := err.(*rest.ValidationError)
+				var verr *rest.ValidationError
+				errors.As(err, &verr)
 				Expect(verr.Errors).To(HaveLen(1))
 				Expect(verr.Errors).To(HaveKeyWithValue("currentPassword", "ra.validation.required"))
 			})
@@ -145,7 +149,8 @@ var _ = Describe("UserRepository", func() {
 				user := *loggedUser
 				user.CurrentPassword = "abc123"
 				err := validatePasswordChange(&user, loggedUser)
-				verr := err.(*rest.ValidationError)
+				var verr *rest.ValidationError
+				errors.As(err, &verr)
 				Expect(verr.Errors).To(HaveLen(1))
 				Expect(verr.Errors).To(HaveKeyWithValue("password", "ra.validation.required"))
 			})
@@ -155,7 +160,8 @@ var _ = Describe("UserRepository", func() {
 				user.CurrentPassword = "current"
 				user.NewPassword = "new"
 				err := validatePasswordChange(&user, loggedUser)
-				verr := err.(*rest.ValidationError)
+				var verr *rest.ValidationError
+				errors.As(err, &verr)
 				Expect(verr.Errors).To(HaveLen(1))
 				Expect(verr.Errors).To(HaveKeyWithValue("currentPassword", "ra.validation.passwordDoesNotMatch"))
 			})
@@ -186,8 +192,11 @@ var _ = Describe("UserRepository", func() {
 		It("returns ValidationError if username already exists", func() {
 			var newUser = &model.User{ID: "2", UserName: "johndoe"}
 			err := validateUsernameUnique(repo, newUser)
-			Expect(err).To(BeAssignableToTypeOf(&rest.ValidationError{}))
-			Expect(err.(*rest.ValidationError).Errors).To(HaveKeyWithValue("userName", "ra.validation.unique"))
+			var verr *rest.ValidationError
+			isValidationError := errors.As(err, &verr)
+
+			Expect(isValidationError).To(BeTrue())
+			Expect(verr.Errors).To(HaveKeyWithValue("userName", "ra.validation.unique"))
 		})
 		It("returns generic error if repository call fails", func() {
 			repo.Error = errors.New("fake error")

server/subsonic/album_lists_test.go

@@ -2,6 +2,7 @@ package subsonic
 
 import (
 	"context"
+	"errors"
 	"net/http/httptest"
 
 	"github.com/navidrome/navidrome/server/subsonic/responses"
@@ -46,9 +47,12 @@ var _ = Describe("AlbumListController", func() {
 		It("should fail if missing type parameter", func() {
 			r := newGetRequest()
 			_, err := controller.GetAlbumList(w, r)
+			var subErr subError
+			isSubError := errors.As(err, &subErr)
 
-			Expect(err).To(MatchError("required 'type' parameter is missing"))
-			Expect(err.(subError).code).To(Equal(responses.ErrorMissingParameter))
+			Expect(isSubError).To(BeTrue())
+			Expect(subErr).To(MatchError("required 'type' parameter is missing"))
+			Expect(subErr.code).To(Equal(responses.ErrorMissingParameter))
 		})
 
 		It("should return error if call fails", func() {
@@ -58,7 +62,9 @@ var _ = Describe("AlbumListController", func() {
 			_, err := controller.GetAlbumList(w, r)
 
 			Expect(err).ToNot(BeNil())
-			Expect(err.(subError).code).To(Equal(responses.ErrorGeneric))
+			var subErr subError
+			errors.As(err, &subErr)
+			Expect(subErr.code).To(Equal(responses.ErrorGeneric))
 		})
 	})
 
@@ -82,8 +88,11 @@ var _ = Describe("AlbumListController", func() {
 			r := newGetRequest()
 			_, err := controller.GetAlbumList2(w, r)
 
-			Expect(err).To(MatchError("required 'type' parameter is missing"))
-			Expect(err.(subError).code).To(Equal(responses.ErrorMissingParameter))
+			var subErr subError
+			errors.As(err, &subErr)
+
+			Expect(subErr).To(MatchError("required 'type' parameter is missing"))
+			Expect(subErr.code).To(Equal(responses.ErrorMissingParameter))
 		})
 
 		It("should return error if call fails", func() {
@@ -92,8 +101,10 @@ var _ = Describe("AlbumListController", func() {
 
 			_, err := controller.GetAlbumList2(w, r)
 
-			Expect(err).ToNot(BeNil())
-			Expect(err.(subError).code).To(Equal(responses.ErrorGeneric))
+			var subErr subError
+			errors.As(err, &subErr)
+			Expect(subErr).ToNot(BeNil())
+			Expect(subErr.code).To(Equal(responses.ErrorGeneric))
 		})
 	})
 })

server/subsonic/api.go

@@ -183,7 +183,8 @@ func h(r chi.Router, path string, f handler) {
 		res, err := f(w, r)
 		if err != nil {
 			// If it is not a Subsonic error, convert it to an ErrorGeneric
-			if _, ok := err.(subError); !ok {
+			var subErr subError
+			if !errors.As(err, &subErr) {
 				if errors.Is(err, model.ErrNotFound) {
 					err = newError(responses.ErrorDataNotFound, "data not found")
 				} else {
@@ -233,8 +234,9 @@ func h410(r chi.Router, paths ...string) {
 func sendError(w http.ResponseWriter, r *http.Request, err error) {
 	response := newResponse()
 	code := responses.ErrorGeneric
-	if e, ok := err.(subError); ok {
-		code = e.code
+	var subErr subError
+	if errors.As(err, &subErr) {
+		code = subErr.code
 	}
 	response.Status = "failed"
 	response.Error = &responses.Error{Code: code, Message: err.Error()}