Background process check callback

README.md

@@ -46,14 +46,15 @@ Using refresh as a library also opens the ability to add a [Callback](https://gi
 ### Structs
 ```go
 type Config struct {
-	RootPath       string   `toml:"root_path"`
-	BackgroundExec string   `toml:"background_exec"` // Execute that stays running and is unaffected by any reloads npm run dev for example
-	Ignore         Ignore   `toml:"ignore"`
-	ExecList       []string `toml:"exec_list"` // See [Execute Lifecycle](https://github.com/atterpac/refresh#execute-lifecycle)
-	LogLevel       string   `toml:"log_level"`
-	Debounce       int      `toml:"debounce"`
-	Callback       func(*EventCallback) EventHandle
-	Slog           *slog.Logger
+	RootPath        string   `toml:"root_path"`
+	BackgroundExec  string   `toml:"background_exec"` // Execute that stays running and is unaffected by any reloads npm run dev for example
+    BackgroundCheck bool     `toml:"background_check"`
+	Ignore          Ignore   `toml:"ignore"`
+	ExecList        []string `toml:"exec_list"` // See [Execute Lifecycle](https://github.com/atterpac/refresh#execute-lifecycle)
+	LogLevel        string   `toml:"log_level"`
+	Debounce        int      `toml:"debounce"`
+	Callback        func(*EventCallback) EventHandle
+	Slog            *slog.Logger
 }
 
 type Ignore struct {
@@ -64,9 +65,11 @@ type Ignore struct {
 }
 
 type Execute struct {
-	Cmd        string
-	IsBlocking bool // Should the next command wait for this command to finish 
-	IsPrimary  bool // Only one primary command can be run at a time
+	Cmd          string      `toml:"cmd" yaml:"cmd"`                     // Execute command
+	ChangeDir    string      `toml:"dir" yaml:"dir"`                     // If directory needs to be changed to call this command relative to the root path
+	IsBlocking   bool        `toml:"blocking" yaml:"blocking"`           // Should the following executes wait for this one to complete
+	IsPrimary    bool        `toml:"primary" yaml:"primary"`             // Only one primary command can be run at a time
+	DelayNext    int         `toml:"delay_next" yaml:"delay_next"`       // Delay in milliseconds before running command
 }
 ```
 
@@ -256,6 +259,8 @@ log_level = "info"
 # Debounce setting for ignoring reptitive file system notifications
 debounce = 1000 # Milliseconds
 # Sets what files the watcher should ignore
+background_check = true
+
 [config.ignore]
 # Ignore follows normal pattern matching including /**/
 # Directories to ignore
@@ -268,6 +273,8 @@ watched_extensions = ["*.go"]
 git_ignore = true
 
 # Runs process in the background and doesnt restart when a refresh is triggered
+# Vite dev and other processes take varying durations and the following commands might rely on them being "complete"
+# This is where setting background_check = true and using a callback in golang library to confirm its state
 [config.background]
 cmd="vite dev"
 
@@ -295,6 +302,16 @@ cmd="./app"
 primary=true
 ```
 
+### Background Check Callback
+There are instances where you want to wait for the "build" steps for something like vite or a server connection that could take a varying amount
+of time to reach a ready state. Refresh adds `engine.AttachBackgroundCallback()` which will hault the execute commands until the callback returns 
+true (or false for error and shutting down). This could be used along side a ping to the vite port for example to ensure it is reached before 
+running commands that rely on it. This requires 3 things
+
+- `background_check = true` in your config.toml or setting the equivalent in golang structs
+-  A callback function that is `func() bool` and returns true when ready and false when errored or exited 
+-  Attaching the callback via `engine.AttachBackgroundCallback()` prior to running `engine.Start()`
+
 #### Flags
 This method is possible but not the most verbose and controlled way to use refresh
 

cmd/refresh/main.go

@@ -11,7 +11,7 @@ import (
 )
 
 func main() {
-	var version string = "0.4.3"
+	var version string = "0.4.4"
 
 	var rootPath string
 	var execCommand string

engine/config.go

@@ -13,21 +13,22 @@ import (
 )
 
 type Config struct {
-	RootPath         string    `toml:"root_path" yaml:"root_path"`
-	BackgroundStruct Execute   `toml:"background" yaml:"background"`
-	Ignore           Ignore    `toml:"ignore" yaml:"ignore"`
-	ExecStruct       []Execute `toml:"executes" yaml:"executes"`
-	ExecList         []string  `toml:"exec_list" yaml:"exec_list"`
-	LogLevel         string    `toml:"log_level" yaml:"log_level"`
-	Debounce         int       `toml:"debounce" yaml:"debounce"`
-	Callback         func(*EventCallback) EventHandle
-	Slog             *slog.Logger
-	ignoreMap        ignoreMap
-	externalSlog     bool
+	RootPath           string      `toml:"root_path" yaml:"root_path"`
+	BackgroundStruct   Execute     `toml:"background" yaml:"background"`
+	BackgroundCallback func() bool `toml:"-" yaml:"-"`
+	Ignore             Ignore      `toml:"ignore" yaml:"ignore"`
+	ExecStruct         []Execute   `toml:"executes" yaml:"executes"`
+	ExecList           []string    `toml:"exec_list" yaml:"exec_list"`
+	LogLevel           string      `toml:"log_level" yaml:"log_level"`
+	Debounce           int         `toml:"debounce" yaml:"debounce"`
+	Callback           func(*EventCallback) EventHandle
+	Slog               *slog.Logger
+	ignoreMap          ignoreMap
+	externalSlog       bool
 }
 
 // Reads a config.toml file and returns the engine
-func (engine *Engine) readConfigFile(path string) *Engine{
+func (engine *Engine) readConfigFile(path string) *Engine {
 	if _, err := toml.DecodeFile(path, &engine); err != nil {
 		slog.Error("Error reading config file")
 		slog.Error(err.Error())
@@ -48,7 +49,6 @@ func (engine *Engine) readConfigYaml(path string) *Engine {
 	}
 	return engine
 }
-
 
 // Verify required data is present in config
 func (engine *Engine) verifyConfig() {
@@ -161,3 +161,4 @@ func changeWorkingDirectory(path string) {
 		slog.Error("Setting new directory", "dir", path)
 	}
 }
+

engine/engine.go

@@ -29,16 +29,27 @@ func (engine *Engine) Start() error {
 		engine.Config.ignoreMap.git = readGitIgnore(engine.Config.RootPath)
 	}
 	go backgroundExec(engine.Config.BackgroundStruct.Cmd)
+	if engine.Config.BackgroundStruct.BackgroundCheck {
+		if engine.Config.BackgroundCallback == nil {
+			slog.Error("Background Callback not set")
+			return errors.New("Background Callback not set")
+		}
+		ok := engine.Config.BackgroundCallback()
+		if !ok {
+			slog.Error("Background Callback Failed")
+			return errors.New("Background Callback Failed")
+		}
+	}
 	waitTime := time.Duration(engine.Config.BackgroundStruct.DelayNext) * time.Millisecond
 	time.Sleep(waitTime)
 	go engine.reloadProcess()
 	trapChan := make(chan error)
-	go engine.SigTrap(trapChan)
+	go engine.sigTrap(trapChan)
 	go engine.watch()
 	return <-trapChan
 }
 
-func (engine *Engine) SigTrap(ch chan error) {
+func (engine *Engine) sigTrap(ch chan error) {
 	signalChan := make(chan os.Signal, 1)
 	signal.Notify(signalChan, os.Interrupt)
 	go func() {
@@ -98,3 +109,8 @@ func NewEngineFromYAML(confPath string) *Engine {
 	engine.verifyConfig()
 	return &engine
 }
+
+func (engine *Engine) AttachBackgroundCallback(callback func() bool) *Engine {
+	engine.Config.BackgroundCallback = callback
+	return engine
+}

engine/execute.go

@@ -10,12 +10,13 @@ import (
 )
 
 type Execute struct {
-	Cmd        string      `toml:"cmd" yaml:"cmd"`               // Execute command
-	ChangeDir  string      `toml:"dir" yaml:"dir"`               // If directory needs to be changed to call this command relative to the root path
-	IsBlocking bool        `toml:"blocking" yaml:"blocking"`     // Should the following executes wait for this one to complete
-	IsPrimary  bool        `toml:"primary" yaml:"primary"`       // Only one primary command can be run at a time
-	DelayNext  int         `toml:"delay_next" yaml:"delay_next"` // Delay in milliseconds before running command
-	process    *os.Process // Stores the Exec.Start() process
+	Cmd             string      `toml:"cmd" yaml:"cmd"`                           // Execute command
+	ChangeDir       string      `toml:"dir" yaml:"dir"`                           // If directory needs to be changed to call this command relative to the root path
+	IsBlocking      bool        `toml:"blocking" yaml:"blocking"`                 // Should the following executes wait for this one to complete
+	IsPrimary       bool        `toml:"primary" yaml:"primary"`                   // Only one primary command can be run at a time
+	DelayNext       int         `toml:"delay_next" yaml:"delay_next"`             // Delay in milliseconds before running command
+	BackgroundCheck bool        `toml:"background_check" yaml:"background_check"` // Should the background callback be run
+	process         *os.Process // Stores the Exec.Start() process
 }
 
 var KILL_STALE = Execute{

example/example.toml

@@ -9,6 +9,7 @@ root_path = "./test"
 log_level = "debug" 
 # Debounce setting for ignoring reptitive file system notifications
 debounce = 1000 # Milliseconds
+
 # Sets what files the watcher should ignore
 [config.ignore]
 # Directories to ignore
@@ -21,6 +22,8 @@ watched_extension = ["*.go"]
 # Background commands are run in the background and are not affected by any file changes
 [config.background]
 cmd="pwd"
+# Engine will check for a callback that has to be added in golang to verify if the background process was successful before starting the next command
+background_check=true
 # Executes are run in order
 # cmd is the command to run
 # blocking will block the next command from running until it is complete

example/example.yaml

@@ -13,6 +13,7 @@ config:
       - '*.go'
   background:
     cmd: pwd
+    background_check: true
   executes:
     - cmd: go mod tidy
       blocking: true

example/go.mod

@@ -6,6 +6,7 @@ require github.com/atterpac/refresh v0.1.0
 
 require (
 	github.com/BurntSushi/toml v1.3.2 // indirect
+	github.com/alexbrainman/ps v0.0.0-20171229230509-b3e1b4a15894 // indirect
 	github.com/lmittmann/tint v1.0.3 // indirect
 	github.com/rjeczalik/notify v0.9.3 // indirect
 	golang.org/x/sys v0.14.0 // indirect

example/go.sum

@@ -1,5 +1,7 @@
 github.com/BurntSushi/toml v1.3.2 h1:o7IhLm0Msx3BaB+n3Ag7L8EVlByGnpq14C4YWiu/gL8=
 github.com/BurntSushi/toml v1.3.2/go.mod h1:CxXYINrC8qIiEnFrOxCa7Jy5BFHlXnUU2pbicEuybxQ=
+github.com/alexbrainman/ps v0.0.0-20171229230509-b3e1b4a15894 h1:A6LgNoQeWttVPnIRYzKsbex/HePFxYT9ygCZvgVJDU0=
+github.com/alexbrainman/ps v0.0.0-20171229230509-b3e1b4a15894/go.mod h1:Wgrp3f69GNEJz6CdHKtBqKAWdmYTd1K9IlOV+uuv4Uw=
 github.com/lmittmann/tint v1.0.3 h1:W5PHeA2D8bBJVvabNfQD/XW9HPLZK1XoPZH0cq8NouQ=
 github.com/lmittmann/tint v1.0.3/go.mod h1:HIS3gSy7qNwGCj+5oRjAutErFBl4BzdQP6cJZ0NfMwE=
 github.com/rjeczalik/notify v0.9.3 h1:6rJAzHTGKXGj76sbRgDiDcYj/HniypXmSJo1SWakZeY=

example/main.go

@@ -1,6 +1,8 @@
 package main
 
 import (
+	"time"
+
 	refresh "github.com/atterpac/refresh/engine"
 )
 
@@ -43,9 +45,16 @@ func main() {
 	}
 
 	// watch := refresh.NewEngineFromConfig(config)
-	watch := refresh.NewEngineFromYAML("./example.yaml")
+	watch := refresh.NewEngineFromTOML("./example.toml")
 
-	watch.Start()
+	watch.AttachBackgroundCallback(func() bool {
+		time.Sleep(5000 * time.Millisecond)
+		return true
+	})
+	err := watch.Start()
+	if err != nil {
+		panic(err)
+	}
 
 	<-make(chan struct{})
 }