feat: parameterize CI pipeline

cfg/config.go

@@ -0,0 +1,44 @@
+package cfg
+
+import (
+	"log"
+	"os/exec"
+	"strings"
+
+	"github.com/joho/godotenv"
+	"github.com/kelseyhightower/envconfig"
+)
+
+type Config struct {
+	ScriptBinaryPath  string `required:"true" split_words:"true"`
+	WebhookScriptPath string `required:"true" split_words:"true"`
+	FileToWatchPath   string `required:"true" split_words:"true"`
+}
+
+func rootDir() string {
+	cmdOut, err := exec.Command("git", "rev-parse", "--show-toplevel").Output()
+	if err != nil {
+		log.Fatalf("exec.Command: %s", err)
+		return ""
+	}
+
+	rootDir := strings.TrimSpace(string(cmdOut))
+	return rootDir
+}
+
+func NewConfig(isProd bool) *Config {
+	if !isProd {
+		err := godotenv.Load(rootDir() + "/.env")
+		if err != nil {
+			log.Fatalf("environment variable ENV is empty and an error occurred while loading the .env file\n")
+		}
+	}
+
+	cfg := &Config{}
+	err := envconfig.Process("", cfg)
+	if err != nil {
+		log.Fatalf("envconfig.Process: %s\n", err)
+	}
+
+	return cfg
+}

go.mod

@@ -0,0 +1,11 @@
+module filelistener
+
+go 1.19
+
+require (
+	github.com/fsnotify/fsnotify v1.6.0
+	github.com/joho/godotenv v1.5.1
+	github.com/kelseyhightower/envconfig v1.4.0
+)
+
+require golang.org/x/sys v0.0.0-20220908164124-27713097b956 // indirect

go.sum

@@ -0,0 +1,8 @@
+github.com/fsnotify/fsnotify v1.6.0 h1:n+5WquG0fcWoWp6xPWfHdbskMCQaFnG6PfBrh1Ky4HY=
+github.com/fsnotify/fsnotify v1.6.0/go.mod h1:sl3t1tCWJFWoRz9R8WJCbQihKKwmorjAbSClcnxKAGw=
+github.com/joho/godotenv v1.5.1 h1:7eLL/+HRGLY0ldzfGMeQkb7vMd0as4CfYvUVzLqw0N0=
+github.com/joho/godotenv v1.5.1/go.mod h1:f4LDr5Voq0i2e/R5DDNOoa2zzDfwtkZa6DnEwAbqwq4=
+github.com/kelseyhightower/envconfig v1.4.0 h1:Im6hONhd3pLkfDFsbRgu68RDNkGF1r3dvMUtDTo2cv8=
+github.com/kelseyhightower/envconfig v1.4.0/go.mod h1:cccZRl6mQpaq41TPp5QxidR+Sa3axMbJDNb//FQX6Gg=
+golang.org/x/sys v0.0.0-20220908164124-27713097b956 h1:XeJjHH1KiLpKGb6lvMiksZ9l0fVUh+AmGcm0nOMEBOY=
+golang.org/x/sys v0.0.0-20220908164124-27713097b956/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=

main .go

@@ -0,0 +1,81 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"os/exec"
+
+	"filelistener/cfg"
+
+	"github.com/fsnotify/fsnotify"
+)
+
+func main() {
+	isProd := os.Getenv("ENV") == "prod"
+	config := cfg.NewConfig(isProd)
+
+	// Create new watcher.
+	watcher, err := fsnotify.NewWatcher()
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer watcher.Close()
+
+	// Start listening for events.
+	go func() {
+		for {
+			select {
+			case event, ok := <-watcher.Events:
+				if !ok {
+					log.Printf("<-watcher.Events: %s\n", err)
+					return
+				}
+				if !event.Has(fsnotify.Write) {
+					log.Printf("is not Write: %s\n", event.Name)
+					continue
+				}
+
+				if err := deploy(config.ScriptBinaryPath, config.WebhookScriptPath); err != nil {
+					log.Printf("deploy: %s\n", err)
+					continue
+				}
+			case err, ok := <-watcher.Errors:
+				if !ok {
+					return
+				}
+				log.Printf("<-watcher.Errors: %s\n", err)
+			}
+		}
+	}()
+
+	// Add a path.
+	err = watcher.Add(config.FileToWatchPath)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	// Block main goroutine forever.
+	<-make(chan struct{})
+}
+
+func deploy(binaryPath, scriptPath string) error {
+	err := execute(binaryPath, scriptPath)
+	if err != nil {
+		return fmt.Errorf("execute: %s", err)
+	}
+	log.Println("deploy done")
+	return nil
+}
+
+func execute(binaryPath, scriptPath string) error {
+	cmd := exec.Command(binaryPath, scriptPath)
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+
+	if err := cmd.Run(); err != nil {
+		return fmt.Errorf("cmd.Run %s", err)
+	}
+
+	return nil
+}