[WIP] Refactor podman system connection

* Add support to manage multiple connections
  * Add connection
  * Remove connection
  * Rename connection
  * Set connection as default
  * Add markdown/man pages
* Fix recursion in hack/xref-helpmsgs-manpages

Signed-off-by: Jhon Honce <jhonce@redhat.com>

1 files changed, 13 insertions, 188 deletions

diff --git a/cmd/podman/system/connection.go b/cmd/podman/system/connection.go
index 9f26a0df6..b1c538803 100644
--- a/cmd/podman/system/connection.go
+++ b/cmd/podman/system/connection.go
@@ -1,209 +1,34 @@
 package system
 
 import (
-	"bytes"
-	"fmt"
-	"net"
-	"net/url"
-	"os"
-	"os/user"
-	"regexp"
-
-	"github.com/containers/common/pkg/config"
 	"github.com/containers/libpod/v2/cmd/podman/registry"
-	"github.com/containers/libpod/v2/libpod/define"
+	"github.com/containers/libpod/v2/cmd/podman/validate"
 	"github.com/containers/libpod/v2/pkg/domain/entities"
-	"github.com/containers/libpod/v2/pkg/terminal"
-	"github.com/pkg/errors"
-	"github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
-	"golang.org/x/crypto/ssh"
-	"golang.org/x/crypto/ssh/agent"
 )
 
-const schemaPattern = "^[A-Za-z][A-Za-z0-9+.-]*:"
-
 var (
-	// Skip creating engines since this command will obtain connection information to engine
+	// Skip creating engines since this command will obtain connection information to said engines
 	noOp = func(cmd *cobra.Command, args []string) error {
 		return nil
 	}
-	connectionCmd = &cobra.Command{
-		Use:  "connection [flags] DESTINATION",
-		Args: cobra.ExactArgs(1),
-		Long: `Store ssh destination information in podman configuration.
-  "destination" is of the form [user@]hostname or
-  an URI of the form ssh://[user@]hostname[:port]
-`,
-		Short:              "Record remote ssh destination",
-		PersistentPreRunE:  noOp,
-		PersistentPostRunE: noOp,
-		TraverseChildren:   false,
-		RunE:               connection,
-		Example: `podman system connection server.fubar.com
-  podman system connection --identity ~/.ssh/dev_rsa ssh://root@server.fubar.com:2222
-  podman system connection --identity ~/.ssh/dev_rsa --port 22 root@server.fubar.com`,
-	}
 
-	cOpts = struct {
-		Identity string
-		Port     int
-		UDSPath  string
-	}{}
+	ConnectionCmd = &cobra.Command{
+		Use:                   "connection",
+		Short:                 "Manage remote ssh destinations",
+		Long:                  `Manage ssh destination information in podman configuration`,
+		DisableFlagsInUseLine: true,
+		PersistentPreRunE:     noOp,
+		RunE:                  validate.SubCommandExists,
+		PersistentPostRunE:    noOp,
+		TraverseChildren:      false,
+	}
 )
 
 func init() {
 	registry.Commands = append(registry.Commands, registry.CliCommand{
 		Mode:    []entities.EngineMode{entities.ABIMode, entities.TunnelMode},
-		Command: connectionCmd,
+		Command: ConnectionCmd,
 		Parent:  systemCmd,
 	})
-
-	flags := connectionCmd.Flags()
-	flags.IntVarP(&cOpts.Port, "port", "p", 22, "SSH port number for destination")
-	flags.StringVar(&cOpts.Identity, "identity", "", "path to SSH identity file")
-	flags.StringVar(&cOpts.UDSPath, "socket-path", "", "path to podman socket on remote host. (default '/run/podman/podman.sock' or '/run/user/{uid}/podman/podman.sock)")
-}
-
-func connection(cmd *cobra.Command, args []string) error {
-	// Default to ssh: schema if none given
-	dest := []byte(args[0])
-	if match, err := regexp.Match(schemaPattern, dest); err != nil {
-		return errors.Wrapf(err, "internal regex error %q", schemaPattern)
-	} else if !match {
-		dest = append([]byte("ssh://"), dest...)
-	}
-
-	uri, err := url.Parse(string(dest))
-	if err != nil {
-		return errors.Wrapf(err, "failed to parse %q", string(dest))
-	}
-
-	if uri.User.Username() == "" {
-		if uri.User, err = getUserInfo(uri); err != nil {
-			return err
-		}
-	}
-
-	if cmd.Flag("socket-path").Changed {
-		uri.Path = cmd.Flag("socket-path").Value.String()
-	}
-
-	if cmd.Flag("port").Changed {
-		uri.Host = net.JoinHostPort(uri.Hostname(), cmd.Flag("port").Value.String())
-	}
-
-	if uri.Port() == "" {
-		uri.Host = net.JoinHostPort(uri.Hostname(), cmd.Flag("port").DefValue)
-	}
-
-	if uri.Path == "" {
-		if uri.Path, err = getUDS(cmd, uri); err != nil {
-			return errors.Wrapf(err, "failed to connect to  %q", uri.String())
-		}
-	}
-
-	custom, err := config.ReadCustomConfig()
-	if err != nil {
-		return err
-	}
-
-	if cmd.Flag("identity").Changed {
-		custom.Engine.RemoteIdentity = cOpts.Identity
-	}
-
-	custom.Engine.RemoteURI = uri.String()
-	return custom.Write()
-}
-
-func getUserInfo(uri *url.URL) (*url.Userinfo, error) {
-	var (
-		usr *user.User
-		err error
-	)
-	if u, found := os.LookupEnv("_CONTAINERS_ROOTLESS_UID"); found {
-		usr, err = user.LookupId(u)
-		if err != nil {
-			return nil, errors.Wrapf(err, "failed to find user %q", u)
-		}
-	} else {
-		usr, err = user.Current()
-		if err != nil {
-			return nil, errors.Wrapf(err, "failed to obtain current user")
-		}
-	}
-
-	pw, set := uri.User.Password()
-	if set {
-		return url.UserPassword(usr.Username, pw), nil
-	}
-	return url.User(usr.Username), nil
-}
-
-func getUDS(cmd *cobra.Command, uri *url.URL) (string, error) {
-	var authMethods []ssh.AuthMethod
-	passwd, set := uri.User.Password()
-	if set {
-		authMethods = append(authMethods, ssh.Password(passwd))
-	}
-
-	ident := cmd.Flag("identity")
-	if ident.Changed {
-		auth, err := terminal.PublicKey(ident.Value.String(), []byte(passwd))
-		if err != nil {
-			return "", errors.Wrapf(err, "Failed to read identity %q", ident.Value.String())
-		}
-		authMethods = append(authMethods, auth)
-	}
-
-	if sock, found := os.LookupEnv("SSH_AUTH_SOCK"); found {
-		logrus.Debugf("Found SSH_AUTH_SOCK %q, ssh-agent signer enabled", sock)
-
-		c, err := net.Dial("unix", sock)
-		if err != nil {
-			return "", err
-		}
-		a := agent.NewClient(c)
-		authMethods = append(authMethods, ssh.PublicKeysCallback(a.Signers))
-	}
-
-	config := &ssh.ClientConfig{
-		User:            uri.User.Username(),
-		Auth:            authMethods,
-		HostKeyCallback: ssh.InsecureIgnoreHostKey(),
-	}
-	dial, err := ssh.Dial("tcp", uri.Host, config)
-	if err != nil {
-		return "", errors.Wrapf(err, "failed to connect to %q", uri.Host)
-	}
-	defer dial.Close()
-
-	session, err := dial.NewSession()
-	if err != nil {
-		return "", errors.Wrapf(err, "failed to create new ssh session on %q", uri.Host)
-	}
-	defer session.Close()
-
-	// Override podman binary for testing etc
-	podman := "podman"
-	if v, found := os.LookupEnv("PODMAN_BINARY"); found {
-		podman = v
-	}
-	run := podman + " info --format=json"
-
-	var buffer bytes.Buffer
-	session.Stdout = &buffer
-	if err := session.Run(run); err != nil {
-		return "", errors.Wrapf(err, "failed to run %q", run)
-	}
-
-	var info define.Info
-	if err := json.Unmarshal(buffer.Bytes(), &info); err != nil {
-		return "", errors.Wrapf(err, "failed to parse 'podman info' results")
-	}
-
-	if info.Host.RemoteSocket == nil || len(info.Host.RemoteSocket.Path) == 0 {
-		return "", fmt.Errorf("remote podman %q failed to report its UDS socket", uri.Host)
-	}
-	return info.Host.RemoteSocket.Path, nil
 }