GCP Cloud Run と AWS App Runner のスケーリングの様子をみる

Dockerfile

FROM golang:latest as builder

WORKDIR /opt/server
COPY . .
RUN CGO_ENABLED=0 GOOS=linux go build -o app main.go

FROM alpine:latest
EXPOSE 8080
COPY --from=builder /opt/server/app /opt/server/app
CMD ["/opt/server/app"]

go.mod

module server

go 1.16

loop.sh

#!/bin/bash

URL=$1

while true
do
  printf '%(%H:%M:%S)T: '
  curl -s $URL -w ", time: %{time_starttransfer} s\n"
done

main.go

package main

import (
	"fmt"
	"net/http"
	"os"
	"time"
)

func handler(w http.ResponseWriter, r *http.Request) {
	time.Sleep(time.Second * 1)
	fmt.Fprintf(w, "%#v", os.Environ())
}

func main() {
	http.HandleFunc("/", handler)
	http.ListenAndServe(":8080", nil)
}