Merge pull request #4 from onkernel/sayan/kernel-372-simplify-api-proxy-chain

Add scale to zero plugin

Author: Sayan-

KERNEL_README.md

@@ -0,0 +1,42 @@
+# neko fork for onkernel
+
+This is a public fork of the [m1k1o/neko](https://github.com/m1k1o/neko) repository.
+
+## Overview
+
+We maintain this fork to provide a customized `base` image that is used in our browser images at [onkernel/kernel-images](https://github.com/onkernel/kernel-images/tree/main/images).
+
+## Building
+
+To build images from this fork, use the build script from the repository root:
+
+```bash
+# Build the base image
+./build base
+
+# Build with custom repository and tag
+./build base --repository your-repo/neko --tag custom-tag
+```
+
+The `--repository` and `--tag` options allow you to specify exactly which image you're building, making it easy to reference back to specific builds in `kernel-images`.
+
+## Keeping in sync with upstream
+
+To merge the latest changes from the upstream neko repository:
+
+```bash
+# Run the sync script to create a new branch and merge upstream changes
+./scripts/sync-upstream.sh
+
+# Or merge directly into your current branch
+./scripts/sync-upstream.sh --no-new-branch
+
+# To merge a specific upstream branch
+./scripts/sync-upstream.sh --upstream-branch $branch
+```
+
+After running the sync script:
+
+1. Resolve any merge conflicts
+2. Test the build to ensure compatibility
+3. Push the changes and create a PR for review

server/Dockerfile

@@ -1,4 +1,4 @@
-ARG BASE_IMAGE=golang:1.24-bullseye
+ARG BASE_IMAGE=golang:1.25.0
 FROM $BASE_IMAGE AS server
 
 WORKDIR /src

server/Dockerfile.bookworm

@@ -1,4 +1,4 @@
-ARG BASE_IMAGE=golang:1.24-bookworm
+ARG BASE_IMAGE=golang:1.25-bookworm
 FROM $BASE_IMAGE AS server
 
 WORKDIR /src

server/cmd/serve.go

@@ -3,6 +3,7 @@ package cmd
 import (
 	"os"
 	"os/signal"
+	"syscall"
 
 	"github.com/rs/zerolog"
 	"github.com/rs/zerolog/log"
@@ -236,7 +237,7 @@ func (c *serve) Run(cmd *cobra.Command, args []string) {
 	c.logger.Info().Msg("neko ready")
 
 	quit := make(chan os.Signal, 1)
-	signal.Notify(quit, os.Interrupt)
+	signal.Notify(quit, os.Interrupt, syscall.SIGTERM)
 	sig := <-quit
 
 	c.logger.Warn().Msgf("received %s, attempting graceful shutdown", sig)

server/go.mod

@@ -1,8 +1,6 @@
 module github.com/m1k1o/neko/server
 
-go 1.24.0
-
-toolchain go1.24.5
+go 1.25.0
 
 require (
 	github.com/PaesslerAG/gval v1.2.4
@@ -12,6 +10,7 @@ require (
 	github.com/gorilla/websocket v1.5.3
 	github.com/kataras/go-events v0.0.3
 	github.com/mitchellh/mapstructure v1.5.0
+	github.com/onkernel/kernel-images/server v0.0.0-20250912023508-e0ca1d95b771
 	github.com/pion/ice/v2 v2.3.38
 	github.com/pion/interceptor v0.1.40
 	github.com/pion/logging v0.2.4

server/go.sum

@@ -56,6 +56,8 @@ github.com/mitchellh/mapstructure v1.5.0 h1:jeMsZIYE/09sWLaz43PL7Gy6RuMjD2eJVyua
 github.com/mitchellh/mapstructure v1.5.0/go.mod h1:bFUtVrKA4DC2yAKiSyO/QUcy7e+RRV2QTWOzhPopBRo=
 github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 h1:C3w9PqII01/Oq1c1nUAm88MOHcQC9l5mIlSMApZMrHA=
 github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822/go.mod h1:+n7T8mK8HuQTcFwEeznm/DIxMOiR9yIdICNftLE1DvQ=
+github.com/onkernel/kernel-images/server v0.0.0-20250912023508-e0ca1d95b771 h1:Z+Zu7ILww5/4q70h1oA+CYBCM0QCuNtAtGDUxjIyp1A=
+github.com/onkernel/kernel-images/server v0.0.0-20250912023508-e0ca1d95b771/go.mod h1:8BxVW6vmlK9as98BTOYIjsVPpXObs+b4aZyZ23JZf4Y=
 github.com/pelletier/go-toml/v2 v2.2.4 h1:mye9XuhQ6gvn5h28+VilKrrPoQVanw5PMw/TB0t5Ec4=
 github.com/pelletier/go-toml/v2 v2.2.4/go.mod h1:2gIqNv+qfxSVS7cM2xJQKtLSTLUE9V8t9Stt+h56mCY=
 github.com/pion/datachannel v1.5.10 h1:ly0Q26K1i6ZkGf42W7D4hQYR90pZwzFOjTq5AuCKk4o=

server/internal/plugins/manager.go

@@ -13,6 +13,7 @@ import (
 	"github.com/m1k1o/neko/server/internal/config"
 	"github.com/m1k1o/neko/server/internal/plugins/chat"
 	"github.com/m1k1o/neko/server/internal/plugins/filetransfer"
+	"github.com/m1k1o/neko/server/internal/plugins/scaletozero"
 	"github.com/m1k1o/neko/server/pkg/types"
 )
 
@@ -47,6 +48,7 @@ func New(config *config.Plugins) *ManagerCtx {
 	// add built-in plugins
 	manager.plugins.addPlugin(filetransfer.NewPlugin())
 	manager.plugins.addPlugin(chat.NewPlugin())
+	manager.plugins.addPlugin(scaletozero.NewPlugin())
 
 	return manager
 }

server/internal/plugins/scaletozero/config.go

@@ -0,0 +1,23 @@
+package scaletozero
+
+import (
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+)
+
+type Config struct {
+	Enabled bool
+}
+
+func (Config) Init(cmd *cobra.Command) error {
+	cmd.PersistentFlags().Bool("scaletozero.enabled", false, "enable scale-to-zero")
+	if err := viper.BindPFlag("scaletozero.enabled", cmd.PersistentFlags().Lookup("scaletozero.enabled")); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (c *Config) Set() {
+	c.Enabled = viper.GetBool("scaletozero.enabled")
+}

server/internal/plugins/scaletozero/manager.go

@@ -0,0 +1,81 @@
+package scaletozero
+
+import (
+	"context"
+	"sync"
+
+	"github.com/m1k1o/neko/server/pkg/types"
+	"github.com/onkernel/kernel-images/server/lib/scaletozero"
+	"github.com/rs/zerolog"
+	"github.com/rs/zerolog/log"
+)
+
+func NewManager(
+	sessions types.SessionManager,
+	config *Config,
+) *Manager {
+	logger := log.With().Str("module", "scaletozero").Logger()
+
+	return &Manager{
+		logger:   logger,
+		config:   config,
+		sessions: sessions,
+		ctrl:     scaletozero.NewUnikraftCloudController(),
+	}
+}
+
+type Manager struct {
+	logger   zerolog.Logger
+	config   *Config
+	sessions types.SessionManager
+	ctrl     scaletozero.Controller
+	mu       sync.Mutex
+	shutdown bool
+	pending  int
+}
+
+func (m *Manager) Start() error {
+	if !m.config.Enabled {
+		return nil
+	}
+	m.logger.Info().Msg("scale-to-zero plugin enabled")
+
+	m.sessions.OnConnected(func(session types.Session) {
+		m.mu.Lock()
+		defer m.mu.Unlock()
+		if m.shutdown {
+			return
+		}
+
+		m.pending++
+		m.logger.Info().Msgf("connection started, disabling scale-to-zero (pending: %d)", m.pending)
+		m.ctrl.Disable(context.Background())
+	})
+
+	m.sessions.OnDisconnected(func(session types.Session) {
+		m.mu.Lock()
+		defer m.mu.Unlock()
+		if m.shutdown {
+			return
+		}
+
+		m.pending--
+		m.logger.Info().Msgf("connection started, disabling scale-to-zero (pending: %d)", m.pending)
+		m.ctrl.Enable(context.Background())
+	})
+
+	return nil
+}
+
+func (m *Manager) Shutdown() error {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	m.shutdown = true
+
+	m.logger.Info().Msgf("shutdown started, re-enabling scale-to-zero (pending: %d)", m.pending)
+	for i := 0; i < m.pending; i++ {
+		m.ctrl.Enable(context.Background())
+	}
+
+	return nil
+}

server/internal/plugins/scaletozero/plugin.go

@@ -0,0 +1,33 @@
+package scaletozero
+
+import (
+	"github.com/m1k1o/neko/server/pkg/types"
+)
+
+type Plugin struct {
+	config  *Config
+	manager *Manager
+}
+
+func NewPlugin() *Plugin {
+	return &Plugin{
+		config: &Config{},
+	}
+}
+
+func (p *Plugin) Name() string {
+	return PluginName
+}
+
+func (p *Plugin) Config() types.PluginConfig {
+	return p.config
+}
+
+func (p *Plugin) Start(m types.PluginManagers) error {
+	p.manager = NewManager(m.SessionManager, p.config)
+	return p.manager.Start()
+}
+
+func (p *Plugin) Shutdown() error {
+	return p.manager.Shutdown()
+}