init repository

client/client.go

@@ -0,0 +1,64 @@
+package client
+
+import (
+	"context"
+	"errors"
+	"time"
+
+	"github.com/docker/docker/client"
+	"github.com/rs/zerolog/log"
+)
+
+const (
+	WaitConnectionFailed time.Duration = 5 * time.Second
+
+	DockerSwarmHostURL string = "tcp://127.0.0.1:4523"
+	DockerHostURL      string = "unix:///var/run/docker.sock"
+
+	ClientConnectionAttempts int = 4
+)
+
+var ErrSwarmClientError = errors.New("unable to connect to the swarm")
+
+func GetSwarmClient() (*client.Client, error) {
+	return initClientWithRetry(DockerSwarmHostURL, ClientConnectionAttempts)
+}
+
+func GetHostClient() (*client.Client, error) {
+	return initClientWithRetry(DockerHostURL, ClientConnectionAttempts)
+}
+
+func initClient(url string) (*client.Client, error) {
+	cli, err := client.NewClientWithOpts(
+		client.WithHost(url),
+		client.WithAPIVersionNegotiation(),
+	)
+	if err != nil {
+		return cli, err
+	}
+
+	return cli, nil
+}
+
+func initClientWithRetry(url string, attempt int) (*client.Client, error) {
+	var i int
+	for {
+		if i == attempt {
+			return nil, ErrSwarmClientError
+		}
+
+		cli, err := initClient(url)
+		if err != nil {
+			return nil, err
+		}
+
+		if _, err := cli.Ping(context.TODO()); err != nil {
+			log.Error().Str("url", url).Msg("unable to connect to the swarm, retrying...")
+			time.Sleep(WaitConnectionFailed)
+			i++
+			continue
+		}
+
+		return cli, nil
+	}
+}