fix: set connection timeouts + clean up bad contexts

Closes coop-cloud/organising#205.

pkg/client/connection.go

@@ -1,15 +1,53 @@
 package client
 
 import (
+	"context"
+	"net"
+	"net/url"
+
+	commandconnPkg "coopcloud.tech/abra/pkg/client/commandconn"
 	"github.com/docker/cli/cli/connhelper"
+	"github.com/docker/cli/cli/connhelper/ssh"
 	"github.com/docker/cli/cli/context/docker"
 	dCliContextStore "github.com/docker/cli/cli/context/store"
 	dClient "github.com/docker/docker/client"
+	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 )
 
+// GetConnectionHelper returns Docker-specific connection helper for the given URL.
+// GetConnectionHelper returns nil without error when no helper is registered for the scheme.
+//
+// ssh://<user>@<host> URL requires Docker 18.09 or later on the remote host.
+func GetConnectionHelper(daemonURL string) (*connhelper.ConnectionHelper, error) {
+	return getConnectionHelper(daemonURL, nil)
+}
+
+func getConnectionHelper(daemonURL string, sshFlags []string) (*connhelper.ConnectionHelper, error) {
+	u, err := url.Parse(daemonURL)
+	if err != nil {
+		return nil, err
+	}
+	switch scheme := u.Scheme; scheme {
+	case "ssh":
+		sp, err := ssh.ParseURL(daemonURL)
+		if err != nil {
+			return nil, errors.Wrap(err, "ssh host connection is not valid")
+		}
+		return &connhelper.ConnectionHelper{
+			Dialer: func(ctx context.Context, network, addr string) (net.Conn, error) {
+				return commandconnPkg.New(ctx, "ssh", append(sshFlags, sp.Args("docker", "system", "dial-stdio")...)...)
+			},
+			Host: daemonURL,
+		}, nil
+	}
+	// Future version may support plugins via ~/.docker/config.json. e.g. "dind"
+	// See docker/cli#889 for the previous discussion.
+	return nil, err
+}
+
 func newConnectionHelper(daemonURL string) *connhelper.ConnectionHelper {
-	helper, err := connhelper.GetConnectionHelper(daemonURL)
+	helper, err := GetConnectionHelper(daemonURL)
 	if err != nil {
 		logrus.Fatal(err)
 	}