feat: remove old app configs

See #577

pkg/client/configs.go

@@ -0,0 +1,38 @@
+package client
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/docker/docker/api/types/filters"
+	"github.com/docker/docker/api/types/swarm"
+	"github.com/docker/docker/client"
+)
+
+func GetConfigs(cl *client.Client, ctx context.Context, server string, fs filters.Args) ([]swarm.Config, error) {
+	configList, err := cl.ConfigList(ctx, swarm.ConfigListOptions{Filters: fs})
+	if err != nil {
+		return configList, err
+	}
+
+	return configList, nil
+}
+
+func GetConfigNames(configs []swarm.Config) []string {
+	var confNames []string
+
+	for _, conf := range configs {
+		confNames = append(confNames, conf.Spec.Name)
+	}
+
+	return confNames
+}
+
+func RemoveConfigs(cl *client.Client, ctx context.Context, configNames []string, force bool) error {
+	for _, confName := range configNames {
+		if err := cl.ConfigRemove(context.Background(), confName); err != nil {
+			return fmt.Errorf("conf %s: %s", confName, err)
+		}
+	}
+	return nil
+}