[cherry-pick] /cherry-pick (#271) (#283)

Signed-off-by: Emruz Hossain <emruz@appscode.com>

Makefile

@@ -572,3 +572,10 @@ release:
 .PHONY: clean
 clean:
 	rm -rf .go bin
+
+# make and load docker image to kind cluster
+.PHONY: push-to-kind
+push-to-kind: container
+	@echo "Loading docker image into kind cluster...."
+	@kind load docker-image $(REGISTRY)/stash-mysql:$(TAG)
+	@echo "Image has been pushed successfully into kind cluster."

pkg/utils.go

@@ -18,13 +18,15 @@ package pkg
 
 import (
 	"fmt"
+	"time"
 
 	stash "stash.appscode.dev/apimachinery/client/clientset/versioned"
 	"stash.appscode.dev/apimachinery/pkg/restic"
 
 	"github.com/codeskyblue/go-sh"
 	"gomodules.xyz/x/log"
 	core "k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/util/wait"
 	"k8s.io/client-go/kubernetes"
 	"kmodules.xyz/custom-resources/apis/appcatalog/v1alpha1"
 	appcatalog_cs "kmodules.xyz/custom-resources/client/clientset/versioned"
@@ -61,13 +63,24 @@ func waitForDBReady(appBinding *v1alpha1.AppBinding, secret *core.Secret, waitTi
 	shell := sh.NewSession()
 	shell.SetEnv(EnvMySqlPassword, string(secret.Data[MySqlPassword]))
 	args := []interface{}{
-		"ping",
 		"--host", appBinding.Spec.ClientConfig.Service.Name,
-		"--user=root",
-		fmt.Sprintf("--wait=%d", waitTimeout),
+		"-u", string(secret.Data[MySqlUser]),
 	}
 	if appBinding.Spec.ClientConfig.Service.Port != 0 {
 		args = append(args, fmt.Sprintf("--port=%d", appBinding.Spec.ClientConfig.Service.Port))
 	}
-	return shell.Command("mysqladmin", args...).Run()
+
+	// Execute "SELECT 1" query to the database. It should return an error when mysqld is not ready.
+	args = append(args, "-e", "SELECT 1;")
+
+	// don't show the output of the query
+	shell.Stdout = nil
+	return wait.PollImmediate(5*time.Second, time.Duration(waitTimeout)*time.Second, func() (done bool, err error) {
+		if err := shell.Command("mysql", args...).Run(); err == nil {
+			log.Infoln("Database is accepting connection....")
+			return true, nil
+		}
+		log.Infoln("Retrying after 5 seconds....")
+		return false, nil
+	})
 }