add luna.restart functionHEADmaster

5 files changed, 141 insertions, 45 deletions

diff --git a/lua.go b/lua.go
index 11eec3e..79b5ba3 100644
--- a/lua.go
+++ b/lua.go
@@ -36,6 +36,7 @@ type Lua struct {
 	running **Lua
 	yield func()
 	resume func() bool
+	deferred func()
 }
 
 //export luna_run_go_func
@@ -46,19 +47,26 @@ func luna_run_go_func(f C.uintptr_t) C.int {
 }
 
 // Start opens the Lua context with all built-in libraries.
-func (l *Lua) Start() {
+func (l *Lua) Start() error {
+	if l.l != nil {
+		return errors.New("already started")
+	}
 	l.l = C.luaL_newstate()
 	l.running = &l
+	l.yield = nil
+	l.resume = nil
 	C.luaL_openlibs(l.l)
 
 	// Put traceback function at the start of the stack so it's always
 	// possible to refer to it via stack index 1.
 	l.PushGoFunction(TracebackHandler)
+	return nil
 }
 
 // Close closes the Lua context.
 func (l *Lua) Close() {
 	C.lua_close(l.l)
+	l.l = nil
 }
 
 // PCall calls a function with the stack index (-nargs-1) expecting nresults
@@ -71,8 +79,13 @@ func (l *Lua) PCall(nargs int, nresults int, errfunc int) error {
 	if res != C.LUA_OK {
 		errMsg := l.ToString(-1)
 		l.Pop(1)
+		l.deferred = nil
 		return errors.New(errMsg)
 	}
+	if l.deferred != nil {
+		l.deferred()
+		l.deferred = nil
+	}
 	return nil
 }
 
@@ -271,11 +284,7 @@ func (l *Lua) LoadAndCall(code string) error {
 		l.Pop(1)
 		return errors.New(errMsg)
 	}
-	err := l.PCall(0, C.LUA_MULTRET, 1)
-	if err != nil {
-		return err
-	}
-	return nil
+	return l.PCall(0, C.LUA_MULTRET, 1)
 }
 
 // SetGlobal sets a global value at the -1 stack index with the name.
diff --git a/lua_common.go b/lua_common.go
index 29fdab9..616beea 100644
--- a/lua_common.go
+++ b/lua_common.go
@@ -42,12 +42,12 @@ func (l *Lua) PushAny(v any) error {
 	switch v.(type) {
 	case nil:
 		l.PushNil()
-	case string:
-		v, _ := v.(string)
-		l.PushString(v)
 	case func (l *Lua) int:
 		v, _ := v.(func (l *Lua) int)
 		l.PushGoFunction(v)
+	case string:
+		v, _ := v.(string)
+		l.PushString(v)
 	case int:
 		v, _ := v.(int)
 		l.PushNumber(v)
diff --git a/luajit.go b/luajit.go
index 0b1fb55..4c88ccf 100644
--- a/luajit.go
+++ b/luajit.go
@@ -36,6 +36,7 @@ type Lua struct {
 	running **Lua
 	yield func()
 	resume func() bool
+	deferred func()
 }
 
 //export luna_run_go_func
@@ -46,19 +47,26 @@ func luna_run_go_func(f C.uintptr_t) C.int {
 }
 
 // Start opens the Lua context with all built-in libraries.
-func (l *Lua) Start() {
+func (l *Lua) Start() error {
+	if l.l != nil {
+		return errors.New("already started")
+	}
 	l.l = C.luaL_newstate()
 	l.running = &l
+	l.yield = nil
+	l.resume = nil
 	C.luaL_openlibs(l.l)
 
 	// Put traceback function at the start of the stack so it's always
 	// possible to refer to it via stack index 1.
 	l.PushGoFunction(TracebackHandler)
+	return nil
 }
 
 // Close closes the Lua context.
 func (l *Lua) Close() {
 	C.lua_close(l.l)
+	l.l = nil
 }
 
 // PCall calls a function with the stack index (-nargs-1) expecting nresults
@@ -69,8 +77,13 @@ func (l *Lua) PCall(nargs int, nresults int, errfunc int) error {
 	if res != C.LUA_OK {
 		errMsg := l.ToString(-1)
 		l.Pop(1)
+		l.deferred = nil
 		return errors.New(errMsg)
 	}
+	if l.deferred != nil {
+		l.deferred()
+		l.deferred = nil
+	}
 	return nil
 }
 
@@ -268,11 +281,7 @@ func (l *Lua) LoadAndCall(code string) error {
 		l.Pop(1)
 		return errors.New(errMsg)
 	}
-	err := l.PCall(0, C.LUA_MULTRET, 1)
-	if err != nil {
-		return err
-	}
-	return nil
+	return l.PCall(0, C.LUA_MULTRET, 1)
 }
 
 // SetGlobal sets a global value at the -1 stack index with the name.
diff --git a/main.go b/main.go
index 33d1cee..5d9b66b 100644
--- a/main.go
+++ b/main.go
@@ -613,6 +613,34 @@ func main() {
 	module["fs"] = fsModule
 	module["image"] = imageModule
 	module["crypto"] = cryptoModule
+	module["restart"] = func (l *Lua) int {
+		running := false
+		l.deferred = func () {
+			if running {
+				return
+			}
+			for i, wrk := range wrks {
+				if wrk.HasSameLua(l) == false {
+					continue
+				}
+				running = true
+				start := time.Now()
+				err := wrk.Restart()
+				if err != nil {
+					log.Printf("error restarting:\n%s\n", err.Error())
+					return
+				}
+				log.Printf(
+					"worker %d restarted in %s\n",
+					i,
+					time.Now().Sub(start),
+				)
+				go wrk.Listen(msgs)
+			}
+		}
+
+		return luaOk(l, nil)
+	}
 	module["on-eval"] = func (l *Lua) int {
 		var evalFn LuaRef
 		err := l.Scan(&evalFn)
@@ -638,12 +666,16 @@ func main() {
 		wrk := NewWorker()
 		wrks = append(wrks, wrk)
 		go func () {
+			start := time.Now()
 			err := wrk.Start(luaArgv, module)
 			if err != nil {
 				log.Fatal(err)
 			}
-			wrks = append(wrks, wrk)
-			log.Printf("worker %d started\n", i)
+			log.Printf(
+				"worker %d started in %s\n",
+				i,
+				time.Now().Sub(start),
+			)
 			wg.Add(-1)
 			wrk.Listen(msgs)
 		}()
diff --git a/worker.go b/worker.go
index ea4892a..a9d7bc6 100644
--- a/worker.go
+++ b/worker.go
@@ -3,12 +3,12 @@ package main
 import (
 	_ "embed"
 	"errors"
+	"fmt"
 	"io"
 	"log"
 	"net/http"
 	"os"
 	"strings"
-	"sync"
 )
 
 type HTTPRequest struct {
@@ -45,16 +45,15 @@ type Worker struct {
 	lua *Lua
 	routes map[string]LuaRef
 	started bool
-	mu sync.Mutex
+	argv []string
+	module map[string]any
+	stop chan bool
 	evalFn *LuaRef
 }
 
 // NewWorker creates a new instance of Worker type.
 func NewWorker() *Worker {
-	return &Worker {
-		routes: make(map[string]LuaRef),
-		lua: &Lua{},
-	}
+	return &Worker { routes: make(map[string]LuaRef) }
 }
 
 // Start starts the worker:
@@ -66,13 +65,15 @@ func (w *Worker) Start(argv []string, module map[string]any) error {
 	if len(argv) == 0 {
 		return errors.New("argv must at least contain lua file name")
 	}
-	w.mu.Lock()
-	defer w.mu.Unlock()
-
 	if w.started {
 		return errors.New("already started")
 	}
-	w.lua.Start()
+
+	w.lua = &Lua{}
+	err := w.lua.Start()
+	if err != nil {
+		return fmt.Errorf("lua error: %w", err)
+	}
 	defer w.lua.RestoreStackFunc()()
 
 	// emulate passing arguments to the loaded chunk
@@ -80,7 +81,7 @@ func (w *Worker) Start(argv []string, module map[string]any) error {
 	for _, arg := range argv {
 		args = append(args, arg)
 	}
-	err := w.lua.PushArray(args)
+	err = w.lua.PushArray(args)
 	if err != nil {
 		return err
 	}
@@ -123,11 +124,51 @@ func (w *Worker) Start(argv []string, module map[string]any) error {
 	}
 
 	w.started = true
+	w.argv = argv
+	w.module = module
+	return nil
+}
+
+// Stop stops the worker closing the Lua context.
+func (w *Worker) Stop() error {
+	if !w.started {
+		return errors.New("not started yet")
+	}
+	if w.stop != nil {
+		w.stop <- true
+	}
+	w.started = false
+	w.evalFn = nil
+	w.routes = make(map[string]LuaRef)
+	w.lua.Close()
+	return nil
+}
+
+// Restart restarts worker with previous arguments.
+func (w *Worker) Restart() error {
+	if !w.started {
+		return errors.New("not started yet")
+	}
+	oldLua := w.lua
+	w.started = false
+	w.routes = make(map[string]LuaRef)
+	err := w.Start(w.argv, w.module)
+	if err != nil {
+		w.lua.Close()
+		w.lua = oldLua
+		w.started = true
+		return err
+	}
+	if w.stop != nil {
+		w.stop <- true
+	}
+	oldLua.Close()
 	return nil
 }
 
 // Listen starts handling HTTP requests from the queue.
 func (w *Worker) Listen(queue chan *HTTPRequest) {
+	w.stop = make(chan bool)
 	stringListToAny := func(slice []string) []any {
 		res := []any{}
 		for _, v := range slice {
@@ -169,6 +210,12 @@ func (w *Worker) Listen(queue chan *HTTPRequest) {
 			flatQr[k] = stringListToAny(qr[k])
 		}
 		res["query"] = flatQr
+
+		cookies := make(map[string]any)
+		for _, cookie := range req.Cookies() {
+			cookies[cookie.Name] = cookie.Value
+		}
+		res["cookies"] = cookies
 		
 		// if request body is a multipart form: automatically parse it,
 		// save the files and form values and put them in to the
@@ -278,7 +325,7 @@ func (w *Worker) Listen(queue chan *HTTPRequest) {
 			return
 		}
 
-		// TODO: probably it would be better to just use l.Scan()
+		// probably it would be better to just use l.Scan()
 		// here but i'm not really sure if we want to have that
 		// overhead here.
 		code := l.ToInt(-3)
@@ -307,24 +354,26 @@ func (w *Worker) Listen(queue chan *HTTPRequest) {
 		}
 	}
 
-	resCh := make(chan func() bool, 4096)
+	corQueue := make(chan func() bool, 4096)
 outer:
 	for {
 		select {
-		case r, ok := <- queue:
+		case <- w.stop:
+			break outer
+		case req, ok := <- queue:
 			// accept new requests
 			if !ok {
 				break outer
 			}
-			resCh <- NewCoroutine(
+			corQueue <- NewCoroutine(
 				func(yield func(), resume func() bool) {
-					handle(r, yield, func () bool {
-						resCh <- resume
+					handle(req, yield, func () bool {
+						corQueue <- resume
 						return true
 					})
 				},
 			)
-		case resume, ok := <-resCh:
+		case resume, ok := <-corQueue:
 			// coroutine executor
 			if !ok {
 				break outer
@@ -332,14 +381,19 @@ outer:
 			resume()
 		}
 	}
+
+	// exhaust queue with coroutines so every request that started
+	// processing will be answered
+	for i := 0; i < len(corQueue); i++ {
+		resume := <- corQueue
+		resume()
+	}
 }
 
 // Eval evaluates the code in the Lua context. Not safe for execution when
 // there are requests in the processing queue, only meant for development
 // purposes.
 func (w *Worker) Eval(code string) error {
-	w.mu.Lock()
-	defer w.mu.Unlock()
 	if w.evalFn != nil {
 		// FIXME: does this branch pollute stack?
 		w.lua.PushFromRef(*w.evalFn)
@@ -355,14 +409,6 @@ func (w *Worker) SetRoute(route string, handler LuaRef) {
 	w.routes[route] = handler
 }
 
-// Stop stops the worker closing the Lua context. TODO: stop Listen goroutine
-// as well.
-func (w *Worker) Stop() {
-	w.mu.Lock()
-	defer w.mu.Unlock()
-	w.lua.Close()
-}
-
 // HasSameLua checks if the Lua context belongs to the worker.
 func (w *Worker) HasSameLua(l *Lua) bool {
 	return w.lua == l