refactor!: consolidate SSH handling

Closes coop-cloud/organising#389.
Closes coop-cloud/organising#341.
Closes coop-cloud/organising#326.
Closes coop-cloud/organising#380.
Closes coop-cloud/organising#360.

pkg/upstream/commandconn/connection.go

@@ -2,19 +2,15 @@ package commandconn
 
 import (
 	"context"
-	"fmt"
 	"net"
 	"net/url"
 
-	ctxPkg "coopcloud.tech/abra/pkg/context"
-	sshPkg "coopcloud.tech/abra/pkg/ssh"
 	"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.
@@ -37,29 +33,6 @@ func getConnectionHelper(daemonURL string, sshFlags []string) (*connhelper.Conne
 			return nil, errors.Wrap(err, "ssh host connection is not valid")
 		}
 
-		if err := ctxPkg.HasDockerContext("", ctxConnDetails.Host); err != nil {
-			return nil, err
-		}
-
-		if err := sshPkg.EnsureHostKey(ctxConnDetails.Host); err != nil {
-			return nil, err
-		}
-
-		hostConfig, err := sshPkg.GetHostConfig(
-			ctxConnDetails.Host,
-			ctxConnDetails.User,
-			ctxConnDetails.Port,
-			false,
-		)
-		if err != nil {
-			return nil, err
-		}
-		if hostConfig.IdentityFile != "" {
-			msg := "discovered %s as identity file for %s, using for ssh connection"
-			logrus.Debugf(msg, hostConfig.IdentityFile, ctxConnDetails.Host)
-			sshFlags = append(sshFlags, fmt.Sprintf("-o IdentityFile=%s", hostConfig.IdentityFile))
-		}
-
 		return &connhelper.ConnectionHelper{
 			Dialer: func(ctx context.Context, network, addr string) (net.Conn, error) {
 				return New(ctx, "ssh", append(sshFlags, ctxConnDetails.Args("docker", "system", "dial-stdio")...)...)