Merge pull request #1 from ryodocx/dev

first release

Author: ryodocx

.github/workflows/docker.yaml

@@ -0,0 +1,33 @@
+on:
+  push:
+    branches-ignore:
+      - "**"
+    tags:
+      - "v*"
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: docker/setup-qemu-action@v2
+      - uses: docker/setup-buildx-action@v2
+      - uses: docker/metadata-action@v3
+        id: meta
+        with:
+          images: ghcr.io/ryodocx/testserver
+          tags: |
+            type=semver,pattern={{version}}
+            type=semver,pattern={{major}}.{{minor}}
+      - uses: docker/login-action@v2
+        with:
+          registry: ghcr.io
+          username: ryodocx
+          password: ${{ secrets.GITHUB_TOKEN }}
+      - uses: docker/build-push-action@v3
+        with:
+          context: .
+          push: true
+          platforms: linux/amd64,linux/arm64
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}

Dockerfile

@@ -0,0 +1,9 @@
+FROM golang:1.18.3-alpine
+COPY *.go .
+ENV CGO_ENABLED=0
+RUN go build -o server *.go
+
+FROM scratch
+ENV LISTEN_ADDR=0.0.0.0:8080
+COPY --from=0 /go/server .
+CMD [ "/server" ]

README.md

@@ -1,2 +1,22 @@
 # testserver
 HTTP Server for graceful-shutdown testing
+
+## Usage
+
+```sh
+# go install
+go install github.com/ryodocx/testserver@latest
+
+# docker
+docker run --rm -it -p 8080:8080 ghcr.io/ryodocx/testserver
+```
+
+## Environment variables
+
+| env            | default                  | example                                                                                                     | description                                                           |
+|----------------|--------------------------|-------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------|
+| LISTEN_ADDR    | `0.0.0.0:8080`           | `127.0.0.1:8080`                                                                                            | Listen address                                                        |
+| RESPONSE_BODY  | `I'm a testserver`       | `hello world`                                                                                               | HTTP response body                                                    |
+| RESPONSE_SLEEP | `50ms`                   | `0` (without sleep) <br> `200ms` `5s` `0.01h`                                                               | Sleep time during HTTP response                                       |
+| TRAP_SIGNALS   | `[interrupt terminated]` | `0` (disable graceful shutdown) <br> `1,2,15` (enable graceful shutdown for SIGHUP/SIGINT/SIGTERM at Linux) | Trapped Signals for graceful shutdown                                 |
+| GRACE_PERIOD   | `1s`                     | `0` (no wait) <br> `5s` `1m`                                                                                | Grace period before starting shutdown (ignored when `TRAP_SIGNALS=0`) |

main.go

@@ -0,0 +1,109 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"net/http"
+	"os"
+	"os/signal"
+	"strconv"
+	"strings"
+	"syscall"
+	"time"
+)
+
+// default config
+var listenAddr = "127.0.0.1:8080"
+var responseBody []byte = []byte("I'm a testserver")
+var responseSleep time.Duration = 50 * time.Millisecond
+var trapSignals []os.Signal = []os.Signal{syscall.SIGINT, syscall.SIGTERM}
+var gracePeriod time.Duration = 1 * time.Second
+
+func init() {
+	// override default config
+	if v := os.Getenv("LISTEN_ADDR"); v != "" {
+		listenAddr = v
+	}
+	if v := os.Getenv("RESPONSE_BODY"); v != "" {
+		responseBody = []byte(v)
+	}
+	if v, err := time.ParseDuration(os.Getenv("RESPONSE_SLEEP")); err == nil {
+		responseSleep = v
+	}
+	if v := os.Getenv("TRAP_SIGNALS"); v != "" {
+		trapSignals = []os.Signal{}
+		if v == "0" {
+			// disable graceful shutdown
+		} else {
+			// enable graceful shutdown
+			for _, s := range strings.Split(v, ",") {
+				i, err := strconv.Atoi(s)
+				if err != nil {
+					log.Fatalln("invalid 'TRAP_SIGNALS':", s)
+				}
+				trapSignals = append(trapSignals, syscall.Signal(i))
+			}
+		}
+	}
+	if v, err := time.ParseDuration(os.Getenv("GRACE_PERIOD")); err == nil {
+		gracePeriod = v
+	}
+}
+
+func handler(w http.ResponseWriter, req *http.Request) {
+	time.Sleep(responseSleep)
+	w.Write(responseBody)
+}
+
+func main() {
+	fmt.Println("pid =", os.Getpid())
+	fmt.Println("############# Configuration #############")
+	print := func(key string, val interface{}) { fmt.Printf("%-19s%v\n", key, val) }
+	print("LISTEN_ADDR", listenAddr)
+	print("RESPONSE_SLEEP", responseSleep)
+	print("TRAP_SIGNALS", trapSignals)
+	print("GRACE_PERIOD", gracePeriod)
+	fmt.Println("#########################################")
+
+	var srv http.Server
+	srv.Addr = listenAddr
+	http.HandleFunc("/", handler)
+
+	idleConnsClosed := make(chan struct{})
+	go func() {
+
+		// signal monitoring
+		for {
+			sigChan := make(chan os.Signal, 1)
+			signal.Notify(sigChan)
+			signal.Ignore(syscall.SIGURG) // https://golang.hateblo.jp/entry/golang-signal-urgent-io-condition
+			recievedSignal := <-sigChan
+			log.Println("signal recieved:", fmt.Sprintf("%d(%s)", recievedSignal, recievedSignal.String()))
+
+			for _, s := range trapSignals {
+				if recievedSignal == s {
+					goto shutdown
+				}
+			}
+		}
+
+		// graceful shutdown
+	shutdown:
+		log.Println("waiting for shutdown:", gracePeriod)
+		time.Sleep(gracePeriod)
+		log.Println("shutting down...")
+		if err := srv.Shutdown(context.Background()); err != nil {
+			log.Printf("HTTP server Shutdown: %v", err)
+		}
+		close(idleConnsClosed)
+	}()
+
+	// start
+	log.Println("start servering")
+	if err := srv.ListenAndServe(); err != http.ErrServerClosed {
+		log.Fatalf("HTTP server ListenAndServe: %v", err)
+	}
+
+	<-idleConnsClosed
+}