wip: daemon

config/config.go

@@ -16,8 +16,8 @@ const (
 	defaultPath = "/etc/wingmate/"
 	defaultName = "config"
 
-	serviceKey = "service"
+	ServiceKey = "service"
-	cronKey    = "cron"
+	CronKey    = "cron"
 )
 
 var (

config/config_test.go

@@ -1,39 +1,92 @@
 package config
 
 import (
+	"gitea.suyono.dev/suyono/wingmate/files/testconfig"
 	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
 	"os"
 	"strings"
 	"testing"
 )
 
+type testReadArgs struct {
+	cmd  *cobra.Command
+	args []string
+}
+
+type testRead struct {
+	name    string
+	env     map[string]string
+	args    testReadArgs
+	wantErr bool
+	pre     func(t *testing.T, tc *testRead)
+	post    func(t *testing.T, tc *testRead)
+}
+
 func TestRead(t *testing.T) {
 	type args struct {
 		cmd  *cobra.Command
 		args []string
 	}
-	tests := []struct {
+	tests := []testRead{
-		name    string
-		env     map[string]string
-		args    args
-		wantErr bool
-	}{
 		{
 			name: "env",
 			env: map[string]string{
 				strings.ToUpper(envPrefix + "_" + configPathKey):       "/path/to/config",
 				strings.ToUpper(envPrefix + "_" + configSearchPathKey): "/path/one,/path/two",
 			},
-			args: args{
+			args: testReadArgs{
 				nil,
 				[]string{},
 			},
 			wantErr: true,
 		},
+		{
+			name: "env exist",
+			args: testReadArgs{
+				nil,
+				[]string{},
+			},
+			wantErr: false,
+			pre: func(t *testing.T, tc *testRead) {
+				var (
+					f     *os.File
+					err   error
+					fname string
+				)
+				if f, err = os.CreateTemp("", "config-*.yml"); err != nil {
+					t.Fatal("create temp:", err)
+				}
+				fname = f.Name()
+				if _, err = f.WriteString(testconfig.One); err != nil {
+					t.Fatal("writing temp:", err)
+				}
+				if err = f.Close(); err != nil {
+					t.Fatal("closing temp:", err)
+				}
+
+				tc.env = map[string]string{
+					strings.ToUpper(envPrefix + "_" + configPathKey): fname,
+				}
+
+				tc.post = func(t *testing.T, tc *testRead) {
+					_ = os.Remove(fname)
+				}
+			},
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			var err error
+
+			if tt.pre != nil {
+				tt.pre(t, &tt)
+			}
+
+			if tt.post != nil {
+				defer tt.post(t, &tt)
+			}
+
 			for k, v := range tt.env {
 				if err = os.Setenv(k, v); err != nil {
 					t.Fatal("failed", err)
@@ -57,3 +110,82 @@ func TestRead(t *testing.T) {
 		})
 	}
 }
+
+func TestGet(t *testing.T) {
+	type args struct {
+		cmd  *cobra.Command
+		args []string
+	}
+	tests := []testRead{
+		{
+			name: "env exist",
+			args: testReadArgs{
+				nil,
+				[]string{},
+			},
+			wantErr: false,
+			pre: func(t *testing.T, tc *testRead) {
+				var (
+					f     *os.File
+					err   error
+					fname string
+				)
+				if f, err = os.CreateTemp("", "config-*.yml"); err != nil {
+					t.Fatal("create temp:", err)
+				}
+				fname = f.Name()
+				if _, err = f.WriteString(testconfig.One); err != nil {
+					t.Fatal("writing temp:", err)
+				}
+				if err = f.Close(); err != nil {
+					t.Fatal("closing temp:", err)
+				}
+
+				tc.env = map[string]string{
+					strings.ToUpper(envPrefix + "_" + configPathKey): fname,
+				}
+
+				tc.post = func(t *testing.T, tc *testRead) {
+					_ = os.Remove(fname)
+				}
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var err error
+
+			if tt.pre != nil {
+				tt.pre(t, &tt)
+			}
+
+			if tt.post != nil {
+				defer tt.post(t, &tt)
+			}
+
+			for k, v := range tt.env {
+				if err = os.Setenv(k, v); err != nil {
+					t.Fatal("failed", err)
+				}
+			}
+			defer func() {
+				for k := range tt.env {
+					if err = os.Unsetenv(k); err != nil {
+						t.Fatal("failed", err)
+					}
+				}
+			}()
+
+			if err = Read(tt.args.cmd, tt.args.args); err != nil {
+				t.Fatal("fail to read config:", err)
+			}
+
+			t.Log(viper.AllKeys())
+			m := viper.GetStringMap(ServiceKey)
+			for s := range m {
+				t.Log(s)
+				t.Log(viper.GetStringMap(ServiceKey + "." + s))
+			}
+		})
+	}
+}

daemon/daemon.go

@@ -1,9 +1,71 @@
 package daemon
 
-import "github.com/spf13/cobra"
+import (
+	"gitea.suyono.dev/suyono/wingmate/config"
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+	"os/exec"
+)
+
+type InstanceType int
+
+type WingMateDescriptor interface {
+	String() string
+	Name() string
+	InstanceName() string
+	InstanceType() InstanceType
+	Error() string // so the descriptor can be wrapped inside an error
+}
+
+type process struct {
+	cmd        *exec.Cmd
+	descriptor WingMateDescriptor
+}
+
+type daemon struct {
+	running   map[string]process
+	available map[string]process
+	services  map[string]WingMateDescriptor
+	cron      map[string]WingMateDescriptor
+}
+
+const (
+	Service InstanceType = iota
+	Cron
+)
+
+func (t InstanceType) String() string {
+	switch t {
+	case Service:
+		return config.ServiceKey
+	case Cron:
+		return config.CronKey
+	default:
+		return "[unknown instance type]"
+	}
+}
 
 func Start(cmd *cobra.Command, args []string) error {
+	var (
+		err error
+	)
 	_, _ = cmd, args // prevent warnings for unused arguments
 
+	d := &daemon{
+		running:   make(map[string]process),
+		available: make(map[string]process),
+		services:  make(map[string]WingMateDescriptor),
+		cron:      make(map[string]WingMateDescriptor),
+	}
+	if err = d.buildServiceMap(); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (d *daemon) buildServiceMap() error {
+	for s := range viper.GetStringMap(Service.String()) {
+		_ = s //TODO: resume work
+	}
 	return nil
 }

daemon/process.go

@@ -1,23 +1,117 @@
 package daemon
 
 import (
+	"bufio"
 	"fmt"
+	"gitea.suyono.dev/suyono/wingmate/debugframes"
+	"io"
+	"os"
 	"os/exec"
 )
 
 type ProcessConfig interface {
+	Descriptor() WingMateDescriptor
+
+	// Name returns the binary name to be executed, to be passed in to exec.Command
 	Name() string
+
+	// Args returns the arguments for the process, to be passed in to exec.Command
 	Args() []string
 	Env() map[string]string
-	Dir() string
+	WorkingDir() string
+	LogChannel() chan<- any
+	ControlChannel() chan<- any
 }
 
-func StartProcess(config ProcessConfig) error {
+type StreamID int
-	cmd := exec.Command(config.Name(), config.Args()...)
+
-	for k, v := range config.Env() {
+type ProcessLogEntry struct {
+	ID       WingMateDescriptor
+	LogEntry string
+}
+
+const (
+	Stdout StreamID = iota
+	Stderr
+)
+
+func (s StreamID) String() string {
+	switch s {
+	case Stdout:
+		return "stdout"
+	case Stderr:
+		return "stderr"
+	default:
+		return "[unknown stream]"
+	}
+}
+
+func StartProcess(config ProcessConfig) (*exec.Cmd, error) {
+	var (
+		err                    error
+		cmd                    *exec.Cmd
+		k, v                   string
+		stdoutPipe, stderrPipe io.ReadCloser
+	)
+	cmd = exec.Command(config.Name(), config.Args()...)
+	cmd.Env = os.Environ()
+	for k, v = range config.Env() {
 		cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%s", k, v))
 	}
-	cmd.Dir = config.Dir()
+	cmd.Dir = config.WorkingDir()
+	if stdoutPipe, err = cmd.StdoutPipe(); err != nil {
+		return nil, fmt.Errorf("set up stdout pipe on process %w: %w %w", config.Descriptor(), err, debugframes.GetTraces())
+	}
+	if stderrPipe, err = cmd.StderrPipe(); err != nil {
+		return nil, fmt.Errorf("set up stderr pipe on process %w: %w %w", config.Descriptor(), err, debugframes.GetTraces())
+	}
 
-	return nil
+	if err = cmd.Start(); err != nil {
+		return nil, fmt.Errorf("starting process %w: %w %w", config.Descriptor(), err, debugframes.GetTraces())
+	}
+
+	go serviceLogReader(config, stdoutPipe, Stdout)
+	go serviceLogReader(config, stderrPipe, Stderr)
+
+	go serviceWaiter(config, cmd)
+
+	return cmd, nil
+}
+
+func serviceLogReader(config ProcessConfig, stream io.Reader, id StreamID) {
+	out := config.LogChannel()
+	defer func() {
+		if o := recover(); o != nil {
+			out <- o
+			//TODO: include stack trace, make the return object an error
+		}
+	}()
+
+	scanner := bufio.NewScanner(stream)
+	for scanner.Scan() {
+		out <- ProcessLogEntry{
+			ID:       config.Descriptor(),
+			LogEntry: scanner.Text(),
+		}
+	}
+
+	if err := scanner.Err(); err != nil {
+		out <- fmt.Errorf("read stream from %w: %w %w", config.Descriptor(), err, debugframes.GetTraces())
+	}
+}
+
+func serviceWaiter(config ProcessConfig, cmd *exec.Cmd) {
+	ctrl := config.ControlChannel()
+	defer func() {
+		if o := recover(); o != nil {
+			ctrl <- o
+			//TODO: include stack trace
+		}
+	}()
+
+	if err := cmd.Wait(); err != nil {
+		ctrl <- fmt.Errorf("wait error on service %w: %w", config.Descriptor(), err)
+	} else {
+		ctrl <- config.Descriptor()
+	}
 }

daemon/process_unix.go

@@ -1,4 +1,12 @@
 package daemon
 
-func DetectDeadChildProcess() {
+import "golang.org/x/sys/unix"
+
+const (
+	anyChildProcess = -1
+)
+
+func WaitChildProcess() (int, error) {
+	var ws unix.WaitStatus
+	return unix.Wait4(anyChildProcess, &ws, 0, nil)
 }

daemon/process_unix_test.go

@@ -15,7 +15,6 @@ func TestWait(t *testing.T) {
 		err     error
 		pid     int
 		testpid int
-		ws      unix.WaitStatus
 	)
 
 	cmd := exec.Command("sleep", "10")
@@ -37,22 +36,14 @@ func TestWait(t *testing.T) {
 		}
 	}()
 
-	testpid, err = unix.Wait4(-1, &ws, 0, nil)
+	testpid, err = WaitChildProcess()
 	if err != nil {
 		t.Fatal("wait4 error:", err)
 	}
 
-	if ws.Signaled() {
+	//if err = cmd.Wait(); err != nil {
-		t.Log("the child process got signal:", ws.Signal())
-	}
-
-	if ws.Exited() {
-		t.Log("the child process exit with status:", ws.ExitStatus())
-	}
-
-	// if err = cmd.Wait(); err != nil {
 	//	t.Fatal("is this expected?", err)
-	// }
+	//}
 
 	assert.Equal(t, pid, testpid)
 }

files/testconfig/one.go

@@ -0,0 +1,9 @@
+package testconfig
+
+var One = `service:
+  one:
+    command: "mycommand -o output"
+  two:
+    command: ["cmd", "now"]
+    workdir: /
+`

files/testconfig/one.yml

@@ -0,0 +1,6 @@
+service:
+  one:
+    command: "mycommand -o output"
+  two:
+    command: ["cmd", "now"]
+    workdir: /