misc: add test for api readiness

test/api-startup/main.go

+package main
+
+import (
+	"fmt"
+	"log"
+	"net/http"
+	"sync"
+	"time"
+)
+
+func main() {
+	when := make(chan (time.Time), 2)
+	var wg sync.WaitGroup
+	wg.Add(2)
+	for _, port := range []string{"5001", "8080"} {
+		go func(port string) {
+			defer wg.Done()
+			for {
+				r, err := http.Get(fmt.Sprintf("http://127.0.0.1:%s", port))
+				if err != nil {
+					continue
+				}
+				t := time.Now()
+				when <- t
+				log.Println(port, t, r.StatusCode)
+				break
+			}
+		}(port)
+	}
+	wg.Wait()
+	first := <-when
+	second := <-when
+	log.Println(second.Sub(first))
+}