wait for server to be ready before testing

cmd/archeio/main_test.go

@@ -21,9 +21,11 @@ package main
 
 import (
 	"context"
+	"net/http"
 	"os"
 	"os/exec"
 	"testing"
+	"time"
 
 	"sigs.k8s.io/oci-proxy/internal/integration"
 )
@@ -62,11 +64,17 @@ func TestIntegrationMain(t *testing.T) {
 		serverErrChan <- serverCmd.Wait()
 	}()
 
-	// TODO: wait for readyz or similar ...
+	// wait for server to be up and running
 	startErr := <-serverErrChan
 	if startErr != nil {
 		t.Fatalf("Failed to start archeio: %v", err)
 	}
+	if !tryUntil(time.Now().Add(time.Second), func() bool {
+		_, err := http.Get("http://" + testAddr + "/v2/")
+		return err == nil
+	}) {
+		t.Fatal("timed out waiting for archeio to be ready")
+	}
 
 	// TODO: fake being on AWS
 	testPull := func(image string) {
@@ -94,3 +102,15 @@ func TestIntegrationMain(t *testing.T) {
 		t.Fatalf("archeio did not exit cleanly: %v", err)
 	}
 }
+
+// helper that calls `try()`` in a loop until the deadline `until`
+// has passed or `try()`returns true, returns whether try ever returned true
+func tryUntil(until time.Time, try func() bool) bool {
+	for until.After(time.Now()) {
+		if try() {
+			return true
+		}
+		time.Sleep(time.Millisecond * 10)
+	}
+	return false
+}