common errors as variable.

internal/api/members/handler.go

@@ -2,6 +2,7 @@ package members
 
 import (
 	"context"
+	"errors"
 	"net/http"
 
 	"github.com/go-chi/chi"
@@ -68,14 +69,21 @@ func GetMember(r *http.Request) MemberData {
 func (h *MembersHandler) ExtractMember(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		memberId := chi.URLParam(r, "memberId")
+
 		profile, err := h.members.Select(memberId)
 		if err != nil {
+			if errors.Is(err, types.ErrMemberDoesNotExist) {
 				utils.HttpNotFound(w, err)
 			} else {
+				utils.HttpInternalServerError(w, err)
+			}
+
+			return
+		}
+
 		next.ServeHTTP(w, SetMember(r, MemberData{
 			ID:      memberId,
 			Profile: profile,
 		}))
-		}
 	})
 }

internal/capture/broadcast.go

@@ -1,7 +1,6 @@
 package capture
 
 import (
-	"fmt"
 	"strings"
 	"sync"
 
@@ -9,6 +8,7 @@ import (
 	"github.com/rs/zerolog/log"
 
 	"demodesk/neko/internal/capture/gst"
+	"demodesk/neko/internal/types"
 )
 
 type BroacastManagerCtx struct {
@@ -67,7 +67,7 @@ func (manager *BroacastManagerCtx) Url() string {
 
 func (manager *BroacastManagerCtx) createPipeline() error {
 	if manager.pipeline != nil {
-		return fmt.Errorf("pipeline already exists")
+		return types.ErrCapturePipelineAlreadyExists
 	}
 
 	var err error

internal/capture/screencast.go

@@ -1,7 +1,7 @@
 package capture
 
 import (
-	"fmt"
+	"errors"
 	"sync"
 	"sync/atomic"
 	"time"
@@ -93,12 +93,12 @@ func (manager *ScreencastManagerCtx) Image() ([]byte, error) {
 		case sample := <-manager.sample:
 			return sample.Data, nil
 		case <-time.After(1 * time.Second):
-			return nil, fmt.Errorf("timeouted")
+			return nil, errors.New("timeouted")
 		}
 	}
 
 	if manager.image.Data == nil {
-		return nil, fmt.Errorf("image sample not found")
+		return nil, errors.New("image sample not found")
 	}
 
 	return manager.image.Data, nil
@@ -109,7 +109,7 @@ func (manager *ScreencastManagerCtx) start() error {
 	defer manager.mu.Unlock()
 
 	if !manager.enabled {
-		return fmt.Errorf("screenshot pipeline not enabled")
+		return errors.New("screenshot pipeline not enabled")
 	}
 
 	err := manager.createPipeline()
@@ -131,7 +131,7 @@ func (manager *ScreencastManagerCtx) stop() {
 
 func (manager *ScreencastManagerCtx) createPipeline() error {
 	if manager.pipeline != nil {
-		return fmt.Errorf("pipeline already exists")
+		return types.ErrCapturePipelineAlreadyExists
 	}
 
 	var err error

internal/capture/stream.go

@@ -1,7 +1,6 @@
 package capture
 
 import (
-	"fmt"
 	"reflect"
 	"sync"
 
@@ -141,7 +140,7 @@ func (manager *StreamManagerCtx) Started() bool {
 
 func (manager *StreamManagerCtx) createPipeline() error {
 	if manager.pipeline != nil {
-		return fmt.Errorf("pipeline already exists")
+		return types.ErrCapturePipelineAlreadyExists
 	}
 
 	var err error

internal/desktop/filechooserdialog.go

@@ -1,7 +1,7 @@
 package desktop
 
 import (
-	"fmt"
+	"errors"
 	"os/exec"
 	"time"
 )
@@ -46,7 +46,7 @@ func (manager *DesktopManagerCtx) HandleFileChooserDialog(uri string) error {
 
 	// if last command didn't return error, consider dialog as still open
 	if err2 == nil {
-		return fmt.Errorf("unable to select files in dialog")
+		return errors.New("unable to select files in dialog")
 	}
 
 	return nil

internal/member/dummy/provider.go

@@ -1,7 +1,7 @@
 package dummy
 
 import (
-	"fmt"
+	"errors"
 
 	"demodesk/neko/internal/types"
 )
@@ -37,7 +37,7 @@ func (provider *MemberProviderCtx) Authenticate(username string, password string
 }
 
 func (provider *MemberProviderCtx) Insert(username string, password string, profile types.MemberProfile) (string, error) {
-	return "", fmt.Errorf("not implemented")
+	return "", errors.New("not implemented")
 }
 
 func (provider *MemberProviderCtx) Select(id string) (types.MemberProfile, error) {
@@ -54,7 +54,7 @@ func (provider *MemberProviderCtx) UpdateProfile(id string, profile types.Member
 }
 
 func (provider *MemberProviderCtx) UpdatePassword(id string, password string) error {
-	return fmt.Errorf("not implemented")
+	return errors.New("not implemented")
 }
 
 func (provider *MemberProviderCtx) Delete(id string) error {

internal/member/file/provider.go

@@ -2,7 +2,6 @@ package file
 
 import (
 	"encoding/json"
-	"fmt"
 	"io/ioutil"
 	"os"
 
@@ -38,7 +37,7 @@ func (provider *MemberProviderCtx) Authenticate(username string, password string
 
 	// TODO: Use hash function.
 	if entry.Password != password {
-		return "", types.MemberProfile{}, fmt.Errorf("invalid password")
+		return "", types.MemberProfile{}, types.ErrMemberInvalidPassword
 	}
 
 	return id, entry.Profile, nil
@@ -55,7 +54,7 @@ func (provider *MemberProviderCtx) Insert(username string, password string, prof
 
 	_, ok := entries[id]
 	if ok {
-		return "", fmt.Errorf("member ID already exists")
+		return "", types.ErrMemberAlreadyExists
 	}
 
 	entries[id] = MemberEntry{
@@ -75,7 +74,7 @@ func (provider *MemberProviderCtx) UpdateProfile(id string, profile types.Member
 
 	entry, ok := entries[id]
 	if !ok {
-		return fmt.Errorf("member ID does not exist")
+		return types.ErrMemberDoesNotExist
 	}
 
 	entry.Profile = profile
@@ -92,7 +91,7 @@ func (provider *MemberProviderCtx) UpdatePassword(id string, password string) er
 
 	entry, ok := entries[id]
 	if !ok {
-		return fmt.Errorf("member ID does not exist")
+		return types.ErrMemberDoesNotExist
 	}
 
 	// TODO: Use hash function.
@@ -139,7 +138,7 @@ func (provider *MemberProviderCtx) Delete(id string) error {
 
 	_, ok := entries[id]
 	if !ok {
-		return fmt.Errorf("member ID does not exist")
+		return types.ErrMemberDoesNotExist
 	}
 
 	delete(entries, id)
@@ -178,7 +177,7 @@ func (provider *MemberProviderCtx) getEntry(id string) (MemberEntry, error) {
 
 	entry, ok := entries[id]
 	if !ok {
-		return MemberEntry{}, fmt.Errorf("member ID does not exist")
+		return MemberEntry{}, types.ErrMemberDoesNotExist
 	}
 
 	return entry, nil

internal/member/manager.go

@@ -1,7 +1,7 @@
 package member
 
 import (
-	"fmt"
+	"errors"
 	"sync"
 
 	"github.com/rs/zerolog"
@@ -41,7 +41,7 @@ type MemberManagerCtx struct {
 	config     *config.Member
 	providerMu sync.Mutex
 	provider   types.MemberProvider
-	sessionMu  sync.Mutex
+	loginMu    sync.Mutex
 }
 
 func (manager *MemberManagerCtx) Connect() error {
@@ -91,13 +91,10 @@ func (manager *MemberManagerCtx) UpdateProfile(id string, profile types.MemberPr
 	defer manager.providerMu.Unlock()
 
 	// update corresponding session, if exists
-	manager.sessionMu.Lock()
+	err := manager.sessions.Update(id, profile)
-	if _, ok := manager.sessions.Get(id); ok {
+	if err != nil && !errors.Is(err, types.ErrSessionNotFound) {
-		if err := manager.sessions.Update(id, profile); err != nil {
 		manager.logger.Err(err).Msg("error while updating session")
 	}
-	}
-	manager.sessionMu.Unlock()
 
 	return manager.provider.UpdateProfile(id, profile)
 }
@@ -114,13 +111,10 @@ func (manager *MemberManagerCtx) Delete(id string) error {
 	defer manager.providerMu.Unlock()
 
 	// destroy corresponding session, if exists
-	manager.sessionMu.Lock()
+	err := manager.sessions.Delete(id)
-	if _, ok := manager.sessions.Get(id); ok {
+	if err != nil && !errors.Is(err, types.ErrSessionNotFound) {
-		if err := manager.sessions.Delete(id); err != nil {
 		manager.logger.Err(err).Msg("error while deleting session")
 	}
-	}
-	manager.sessionMu.Unlock()
 
 	return manager.provider.Delete(id)
 }
@@ -130,8 +124,8 @@ func (manager *MemberManagerCtx) Delete(id string) error {
 //
 
 func (manager *MemberManagerCtx) Login(username string, password string) (types.Session, string, error) {
-	manager.sessionMu.Lock()
+	manager.loginMu.Lock()
-	defer manager.sessionMu.Unlock()
+	defer manager.loginMu.Unlock()
 
 	id, profile, err := manager.provider.Authenticate(username, password)
 	if err != nil {
@@ -141,7 +135,7 @@ func (manager *MemberManagerCtx) Login(username string, password string) (types.
 	session, ok := manager.sessions.Get(id)
 	if ok {
 		if session.State().IsConnected {
-			return nil, "", fmt.Errorf("session is already connected")
+			return nil, "", types.ErrSessionAlreadyConnected
 		}
 
 		// TODO: Replace session.
@@ -154,12 +148,8 @@ func (manager *MemberManagerCtx) Login(username string, password string) (types.
 }
 
 func (manager *MemberManagerCtx) Logout(id string) error {
-	manager.sessionMu.Lock()
+	manager.loginMu.Lock()
-	defer manager.sessionMu.Unlock()
+	defer manager.loginMu.Unlock()
-
-	if _, ok := manager.sessions.Get(id); !ok {
-		return fmt.Errorf("session not found")
-	}
 
 	return manager.sessions.Delete(id)
 }

internal/member/object/provider.go

@@ -1,8 +1,6 @@
 package object
 
 import (
-	"fmt"
-
 	"demodesk/neko/internal/types"
 )
 
@@ -60,12 +58,12 @@ func (provider *MemberProviderCtx) Authenticate(username string, password string
 
 	entry, ok := provider.entries[id]
 	if !ok {
-		return "", types.MemberProfile{}, fmt.Errorf("member ID does not exist")
+		return "", types.MemberProfile{}, types.ErrMemberDoesNotExist
 	}
 
 	// TODO: Use hash function.
 	if entry.Password != password {
-		return "", types.MemberProfile{}, fmt.Errorf("invalid password")
+		return "", types.MemberProfile{}, types.ErrMemberInvalidPassword
 	}
 
 	return id, entry.Profile, nil
@@ -77,7 +75,7 @@ func (provider *MemberProviderCtx) Insert(username string, password string, prof
 
 	_, ok := provider.entries[id]
 	if ok {
-		return "", fmt.Errorf("member ID already exists")
+		return "", types.ErrMemberAlreadyExists
 	}
 
 	provider.entries[id] = &MemberEntry{
@@ -92,7 +90,7 @@ func (provider *MemberProviderCtx) Insert(username string, password string, prof
 func (provider *MemberProviderCtx) UpdateProfile(id string, profile types.MemberProfile) error {
 	entry, ok := provider.entries[id]
 	if !ok {
-		return fmt.Errorf("member ID does not exist")
+		return types.ErrMemberDoesNotExist
 	}
 
 	entry.Profile = profile
@@ -103,7 +101,7 @@ func (provider *MemberProviderCtx) UpdateProfile(id string, profile types.Member
 func (provider *MemberProviderCtx) UpdatePassword(id string, password string) error {
 	entry, ok := provider.entries[id]
 	if !ok {
-		return fmt.Errorf("member ID does not exist")
+		return types.ErrMemberDoesNotExist
 	}
 
 	// TODO: Use hash function.
@@ -115,7 +113,7 @@ func (provider *MemberProviderCtx) UpdatePassword(id string, password string) er
 func (provider *MemberProviderCtx) Select(id string) (types.MemberProfile, error) {
 	entry, ok := provider.entries[id]
 	if !ok {
-		return types.MemberProfile{}, fmt.Errorf("member ID does not exist")
+		return types.MemberProfile{}, types.ErrMemberDoesNotExist
 	}
 
 	return entry.Profile, nil
@@ -139,7 +137,7 @@ func (provider *MemberProviderCtx) SelectAll(limit int, offset int) (map[string]
 func (provider *MemberProviderCtx) Delete(id string) error {
 	_, ok := provider.entries[id]
 	if !ok {
-		return fmt.Errorf("member ID does not exist")
+		return types.ErrMemberDoesNotExist
 	}
 
 	delete(provider.entries, id)

internal/session/auth.go

@@ -1,7 +1,7 @@
 package session
 
 import (
-	"fmt"
+	"errors"
 	"net/http"
 	"strings"
 	"time"
@@ -39,16 +39,16 @@ func (manager *SessionManagerCtx) CookieClearToken(w http.ResponseWriter, r *htt
 func (manager *SessionManagerCtx) Authenticate(r *http.Request) (types.Session, error) {
 	token, ok := manager.getToken(r)
 	if !ok {
-		return nil, fmt.Errorf("no authentication provided")
+		return nil, errors.New("no authentication provided")
 	}
 
 	session, ok := manager.GetByToken(token)
 	if !ok {
-		return nil, fmt.Errorf("session not found")
+		return nil, types.ErrSessionNotFound
 	}
 
 	if !session.Profile().CanLogin {
-		return nil, fmt.Errorf("login disabled")
+		return nil, types.ErrSessionLoginDisabled
 	}
 
 	return session, nil

internal/session/manager.go

@@ -1,7 +1,7 @@
 package session
 
 import (
-	"fmt"
+	"errors"
 	"sync"
 
 	"github.com/kataras/go-events"
@@ -68,12 +68,12 @@ func (manager *SessionManagerCtx) Create(id string, profile types.MemberProfile)
 	manager.sessionsMu.Lock()
 	if _, ok := manager.sessions[id]; ok {
 		manager.sessionsMu.Unlock()
-		return nil, "", fmt.Errorf("session id already exists")
+		return nil, "", types.ErrSessionAlreadyExists
 	}
 
 	if _, ok := manager.tokens[token]; ok {
 		manager.sessionsMu.Unlock()
-		return nil, "", fmt.Errorf("session token already exists")
+		return nil, "", errors.New("session token already exists")
 	}
 
 	session := &SessionCtx{
@@ -98,7 +98,7 @@ func (manager *SessionManagerCtx) Update(id string, profile types.MemberProfile)
 	session, ok := manager.sessions[id]
 	if !ok {
 		manager.sessionsMu.Unlock()
-		return fmt.Errorf("session id not found")
+		return types.ErrSessionNotFound
 	}
 
 	session.profile = profile
@@ -114,7 +114,7 @@ func (manager *SessionManagerCtx) Delete(id string) error {
 	session, ok := manager.sessions[id]
 	if !ok {
 		manager.sessionsMu.Unlock()
-		return fmt.Errorf("session id not found")
+		return types.ErrSessionNotFound
 	}
 
 	delete(manager.tokens, session.token)

internal/types/capture.go

@@ -2,6 +2,7 @@ package types
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"math"
 	"strings"
@@ -12,6 +13,10 @@ import (
 	"demodesk/neko/internal/types/codec"
 )
 
+var (
+	ErrCapturePipelineAlreadyExists = errors.New("capture pipeline already exists")
+)
+
 type Sample media.Sample
 
 type BroadcastManager interface {

internal/types/member.go

@@ -1,5 +1,13 @@
 package types
 
+import "errors"
+
+var (
+	ErrMemberAlreadyExists   = errors.New("member already exists")
+	ErrMemberDoesNotExist    = errors.New("member does not exist")
+	ErrMemberInvalidPassword = errors.New("invalid password")
+)
+
 type MemberProfile struct {
 	Name               string `json:"name"`
 	IsAdmin            bool   `json:"is_admin"`

internal/types/session.go

@@ -1,6 +1,16 @@
 package types
 
-import "net/http"
+import (
+	"errors"
+	"net/http"
+)
+
+var (
+	ErrSessionNotFound         = errors.New("session not found")
+	ErrSessionAlreadyExists    = errors.New("session already exists")
+	ErrSessionAlreadyConnected = errors.New("session is already connected")
+	ErrSessionLoginDisabled    = errors.New("session login disabled")
+)
 
 type SessionState struct {
 	IsConnected bool `json:"is_connected"`

internal/types/webrtc.go

@@ -1,6 +1,15 @@
 package types
 
-import "github.com/pion/webrtc/v3"
+import (
+	"errors"
+
+	"github.com/pion/webrtc/v3"
+)
+
+var (
+	ErrWebRTCVideoNotFound       = errors.New("webrtc video not found")
+	ErrWebRTCDataChannelNotFound = errors.New("webrtc data channel not found")
+)
 
 type ICEServer struct {
 	URLs       []string `mapstructure:"urls"       json:"urls"`

internal/webrtc/manager.go

@@ -66,7 +66,7 @@ func (manager *WebRTCManagerCtx) Start() {
 	}
 
 	audioListener := func(sample types.Sample) {
-		if err := manager.audioTrack.WriteSample(media.Sample(sample)); err != nil && err != io.ErrClosedPipe {
+		if err := manager.audioTrack.WriteSample(media.Sample(sample)); err != nil {
 			if errors.Is(err, io.ErrClosedPipe) {
 				// The peerConnection has been closed.
 				return
@@ -166,7 +166,7 @@ func (manager *WebRTCManagerCtx) CreatePeer(session types.Session, videoID strin
 	}
 
 	videoListener := func(sample types.Sample) {
-		if err := videoTrack.WriteSample(media.Sample(sample)); err != nil && err != io.ErrClosedPipe {
+		if err := videoTrack.WriteSample(media.Sample(sample)); err != nil {
 			if errors.Is(err, io.ErrClosedPipe) {
 				// The peerConnection has been closed.
 				return
@@ -200,7 +200,7 @@ func (manager *WebRTCManagerCtx) CreatePeer(session types.Session, videoID strin
 	changeVideo := func(videoID string) error {
 		newVideoStream, ok := manager.capture.Video(videoID)
 		if !ok {
-			return fmt.Errorf("video stream not found")
+			return types.ErrWebRTCVideoNotFound
 		}
 
 		// should be new stream started
@@ -357,7 +357,7 @@ func (manager *WebRTCManagerCtx) mediaEngine(videoID string) (*webrtc.MediaEngin
 	// all videos must have the same codec
 	video, ok := manager.capture.Video(videoID)
 	if !ok {
-		return nil, fmt.Errorf("selected video track not found")
+		return nil, types.ErrWebRTCVideoNotFound
 	}
 
 	videoCodec := video.Codec()

internal/webrtc/send.go

@@ -3,7 +3,6 @@ package webrtc
 import (
 	"bytes"
 	"encoding/binary"
-	"fmt"
 
 	"demodesk/neko/internal/types"
 )
@@ -28,8 +27,11 @@ type PayloadCursorImage struct {
 }
 
 func (peer *WebRTCPeerCtx) SendCursorPosition(x, y int) error {
+	peer.mu.Lock()
+	defer peer.mu.Unlock()
+
 	if peer.dataChannel == nil {
-		return fmt.Errorf("no data channel")
+		return types.ErrWebRTCDataChannelNotFound
 	}
 
 	data := PayloadCursorPosition{
@@ -50,8 +52,11 @@ func (peer *WebRTCPeerCtx) SendCursorPosition(x, y int) error {
 }
 
 func (peer *WebRTCPeerCtx) SendCursorImage(cur *types.CursorImage, img []byte) error {
+	peer.mu.Lock()
+	defer peer.mu.Unlock()
+
 	if peer.dataChannel == nil {
-		return fmt.Errorf("no data channel")
+		return types.ErrWebRTCDataChannelNotFound
 	}
 
 	data := PayloadCursorImage{