Add remaining (sans spawn, testbench)

exec/exec.go

@@ -0,0 +1,26 @@
+package exec
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"syscall"
+)
+
+func Exec() {
+	defer fmt.Println("defer println")
+	lsPath, err := exec.LookPath("ls")
+	if err != nil {
+		panic(err)
+	}
+
+	envs := os.Environ()
+
+	// Exec replaces currently running go program and doesn't seem to care for `defer`s either
+	execErr := syscall.Exec(lsPath, []string{"-l", "-a", "-h", "/"}, envs)
+	if execErr != nil {
+		panic(execErr)
+	}
+
+	fmt.Println("Stopping the program")
+}

httpctx/httpctx.go

@@ -0,0 +1,30 @@
+package httpctx
+
+import (
+	"fmt"
+	"log"
+	"net/http"
+	"time"
+)
+
+func helloHandler(w http.ResponseWriter, req *http.Request) {
+	log.Println("hello handler started")
+	ctx := req.Context()
+	defer log.Println("hello handler finishing")
+
+	select {
+	case <-time.After(10 * time.Second):
+		fmt.Fprintln(w, "hello there!")
+	case <-ctx.Done():
+		err := ctx.Err()
+		log.Println("hello error:", err.Error())
+		internalError := http.StatusInternalServerError
+		http.Error(w, err.Error(), internalError)
+	}
+}
+
+func HttpCtx() {
+	log.Println("Server listening on :8002")
+	http.HandleFunc("/hello", helloHandler)
+	http.ListenAndServe(":8002", nil)
+}

main.go

@@ -47,7 +47,10 @@ import (
 	// "git.sangeeth.dev/gobyexample/env"
 	// "git.sangeeth.dev/gobyexample/logging"
 	// "git.sangeeth.dev/gobyexample/httpclient"
-	"git.sangeeth.dev/gobyexample/httpserver"
+	// "git.sangeeth.dev/gobyexample/httpserver"
+	// "git.sangeeth.dev/gobyexample/httpctx"
+	// "git.sangeeth.dev/gobyexample/exec"
+	"git.sangeeth.dev/gobyexample/signals"
 )
 
 func main() {
@@ -97,5 +100,8 @@ func main() {
 	// env.Env()
 	// logging.Logging()
 	// httpclient.HttpClient()
-	httpserver.HttpServer()
+	// httpserver.HttpServer()
+	// httpctx.HttpCtx()
+	// exec.Exec()
+	signals.Signals()
 }

signals/signals.go

@@ -0,0 +1,30 @@
+package signals
+
+import (
+	"fmt"
+	"os"
+	"os/signal"
+	"syscall"
+)
+
+func Signals() {
+	// chan MUST be buffered
+	signals := make(chan os.Signal, 1)
+
+	signal.Notify(signals, syscall.SIGINT, syscall.SIGTERM)
+
+	done := make(chan bool, 1)
+
+	go doWork(done, signals)
+
+	fmt.Println("Awaiting signal")
+	<-done
+	fmt.Println("Received done, program exiting")
+}
+
+func doWork(done chan<- bool, signals <-chan os.Signal) {
+	sig := <-signals
+	fmt.Println()
+	fmt.Println("Received signal:", sig)
+	done <- true
+}