Feature: support store group selected node to cache (enable by default)

component/profile/cachefile/cache.go

@@ -0,0 +1,115 @@
+package cachefile
+
+import (
+	"bytes"
+	"encoding/gob"
+	"io/ioutil"
+	"os"
+	"sync"
+
+	"github.com/Dreamacro/clash/component/profile"
+	C "github.com/Dreamacro/clash/constant"
+	"github.com/Dreamacro/clash/log"
+)
+
+var (
+	initOnce     sync.Once
+	fileMode     os.FileMode = 0666
+	defaultCache *CacheFile
+)
+
+type cache struct {
+	Selected map[string]string
+}
+
+// CacheFile store and update the cache file
+type CacheFile struct {
+	path  string
+	model *cache
+	enc   *gob.Encoder
+	buf   *bytes.Buffer
+	mux   sync.Mutex
+}
+
+func (c *CacheFile) SetSelected(group, selected string) {
+	if !profile.StoreSelected.Load() {
+		return
+	}
+
+	c.mux.Lock()
+	defer c.mux.Unlock()
+
+	model, err := c.element()
+	if err != nil {
+		log.Warnln("[CacheFile] read cache %s failed: %s", c.path, err.Error())
+		return
+	}
+
+	model.Selected[group] = selected
+	c.buf.Reset()
+	if err := c.enc.Encode(model); err != nil {
+		log.Warnln("[CacheFile] encode gob failed: %s", err.Error())
+		return
+	}
+
+	if err := ioutil.WriteFile(c.path, c.buf.Bytes(), fileMode); err != nil {
+		log.Warnln("[CacheFile] write cache to %s failed: %s", c.path, err.Error())
+		return
+	}
+}
+
+func (c *CacheFile) SelectedMap() map[string]string {
+	if !profile.StoreSelected.Load() {
+		return nil
+	}
+
+	c.mux.Lock()
+	defer c.mux.Unlock()
+
+	model, err := c.element()
+	if err != nil {
+		log.Warnln("[CacheFile] read cache %s failed: %s", c.path, err.Error())
+		return nil
+	}
+
+	mapping := map[string]string{}
+	for k, v := range model.Selected {
+		mapping[k] = v
+	}
+	return mapping
+}
+
+func (c *CacheFile) element() (*cache, error) {
+	if c.model != nil {
+		return c.model, nil
+	}
+
+	model := &cache{
+		Selected: map[string]string{},
+	}
+
+	if buf, err := ioutil.ReadFile(c.path); err == nil {
+		bufReader := bytes.NewBuffer(buf)
+		dec := gob.NewDecoder(bufReader)
+		if err := dec.Decode(model); err != nil {
+			return nil, err
+		}
+	}
+
+	c.model = model
+	return c.model, nil
+}
+
+// Cache return singleton of CacheFile
+func Cache() *CacheFile {
+	initOnce.Do(func() {
+		buf := &bytes.Buffer{}
+		defaultCache = &CacheFile{
+			path: C.Path.Cache(),
+			buf:  buf,
+			enc:  gob.NewEncoder(buf),
+		}
+	})
+
+	return defaultCache
+}

component/profile/profile.go

@@ -0,0 +1,10 @@
+package profile
+
+import (
+	"go.uber.org/atomic"
+)
+
+var (
+	// StoreSelected is a global switch for storing selected proxy to cache
+	StoreSelected = atomic.NewBool(true)
+)

config/config.go

@@ -73,6 +73,11 @@ type FallbackFilter struct {
 	Domain []string     `yaml:"domain"`
 }
 
+// Profile config
+type Profile struct {
+	StoreSelected bool `yaml:"store-selected"`
+}
+
 // Experimental config
 type Experimental struct{}
 
@@ -82,6 +87,7 @@ type Config struct {
 	DNS          *DNS
 	Experimental *Experimental
 	Hosts        *trie.DomainTrie
+	Profile      *Profile
 	Rules        []C.Rule
 	Users        []auth.AuthUser
 	Proxies      map[string]C.Proxy
@@ -129,6 +135,7 @@ type RawConfig struct {
 	Hosts         map[string]string                 `yaml:"hosts"`
 	DNS           RawDNS                            `yaml:"dns"`
 	Experimental  Experimental                      `yaml:"experimental"`
+	Profile       Profile                           `yaml:"profile"`
 	Proxy         []map[string]interface{}          `yaml:"proxies"`
 	ProxyGroup    []map[string]interface{}          `yaml:"proxy-groups"`
 	Rule          []string                          `yaml:"rules"`
@@ -145,7 +152,7 @@ func Parse(buf []byte) (*Config, error) {
 }
 
 func UnmarshalRawConfig(buf []byte) (*RawConfig, error) {
-	// config with some default value
+	// config with default value
 	rawCfg := &RawConfig{
 		AllowLan:       false,
 		BindAddress:    "*",
@@ -169,6 +176,9 @@ func UnmarshalRawConfig(buf []byte) (*RawConfig, error) {
 				"8.8.8.8",
 			},
 		},
+		Profile: Profile{
+			StoreSelected: true,
+		},
 	}
 
 	if err := yaml.Unmarshal(buf, &rawCfg); err != nil {
@@ -182,6 +192,7 @@ func ParseRawConfig(rawCfg *RawConfig) (*Config, error) {
 	config := &Config{}
 
 	config.Experimental = &rawCfg.Experimental
+	config.Profile = &rawCfg.Profile
 
 	general, err := parseGeneral(rawCfg)
 	if err != nil {

constant/path.go

@@ -56,3 +56,7 @@ func (p *path) Resolve(path string) string {
 func (p *path) MMDB() string {
 	return P.Join(p.homeDir, "Country.mmdb")
 }
+
+func (p *path) Cache() string {
+	return P.Join(p.homeDir, ".cache")
+}

hub/executor/executor.go

@@ -6,9 +6,13 @@ import (
 	"os"
 	"sync"
 
+	"github.com/Dreamacro/clash/adapters/outbound"
+	"github.com/Dreamacro/clash/adapters/outboundgroup"
 	"github.com/Dreamacro/clash/adapters/provider"
 	"github.com/Dreamacro/clash/component/auth"
 	"github.com/Dreamacro/clash/component/dialer"
+	"github.com/Dreamacro/clash/component/profile"
+	"github.com/Dreamacro/clash/component/profile/cachefile"
 	"github.com/Dreamacro/clash/component/resolver"
 	"github.com/Dreamacro/clash/component/trie"
 	"github.com/Dreamacro/clash/config"
@@ -72,6 +76,7 @@ func ApplyConfig(cfg *config.Config, force bool) {
 	updateDNS(cfg.DNS)
 	updateHosts(cfg.Hosts)
 	updateExperimental(cfg)
+	updateProfile(cfg)
 }
 
 func GetGeneral() *config.General {
@@ -209,3 +214,38 @@ func updateUsers(users []auth.AuthUser) {
 		log.Infoln("Authentication of local server updated")
 	}
 }
+
+func updateProfile(cfg *config.Config) {
+	profileCfg := cfg.Profile
+
+	profile.StoreSelected.Store(profileCfg.StoreSelected)
+	if profileCfg.StoreSelected {
+		patchSelectGroup(cfg.Proxies)
+	}
+}
+
+func patchSelectGroup(proxies map[string]C.Proxy) {
+	mapping := cachefile.Cache().SelectedMap()
+	if mapping == nil {
+		return
+	}
+
+	for name, proxy := range proxies {
+		outbound, ok := proxy.(*outbound.Proxy)
+		if !ok {
+			continue
+		}
+
+		selector, ok := outbound.ProxyAdapter.(*outboundgroup.Selector)
+		if !ok {
+			continue
+		}
+
+		selected, exist := mapping[name]
+		if !exist {
+			continue
+		}
+
+		selector.Set(selected)
+	}
+}

hub/route/proxies.go

@@ -9,6 +9,7 @@ import (
 
 	"github.com/Dreamacro/clash/adapters/outbound"
 	"github.com/Dreamacro/clash/adapters/outboundgroup"
+	"github.com/Dreamacro/clash/component/profile/cachefile"
 	C "github.com/Dreamacro/clash/constant"
 	"github.com/Dreamacro/clash/tunnel"
 
@@ -91,6 +92,7 @@ func updateProxy(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	cachefile.Cache().SetSelected(proxy.Name(), req.Name)
 	render.NoContent(w, r)
 }