Merge pull request #4105 from technosophos/feature/deisctl-ssh-exec-docker

feat(deisctl): extend SSH to allow exec and docker

Author: technosophos

deisctl/backend/backend.go

@@ -13,6 +13,7 @@ type Backend interface {
 	Stop([]string, *sync.WaitGroup, io.Writer, io.Writer)
 	Scale(string, int, *sync.WaitGroup, io.Writer, io.Writer)
 	SSH(string) error
+	SSHExec(string, string) error
 	ListUnits() error
 	ListUnitFiles() error
 	Status(string) error

deisctl/backend/fleet/ssh.go

@@ -13,51 +13,66 @@ import (
 )
 
 // SSH opens an interactive shell to a machine in the cluster
-func (c *FleetClient) SSH(name string) (err error) {
-	var sshClient *ssh.SSHForwardingClient
+func (c *FleetClient) SSH(name string) error {
+	sshClient, err := c.sshConnect(name)
+	if err != nil {
+		return err
+	}
+
+	defer sshClient.Close()
+	err = ssh.Shell(sshClient)
+	return err
+}
+
+func (c *FleetClient) SSHExec(name, cmd string) error {
+	fmt.Printf("Excuting '%s' on container '%s'\n", cmd, name)
+
+	conn, err := c.sshConnect(name)
+	if err != nil {
+		return err
+	}
+
+	err, _ = ssh.Execute(conn, cmd)
+	return err
+}
+
+func (c *FleetClient) sshConnect(name string) (*ssh.SSHForwardingClient, error) {
 
 	timeout := time.Duration(Flags.SSHTimeout*1000) * time.Millisecond
 
 	ms, err := c.machineState(name)
 	if err != nil {
-		return err
+		return nil, err
 	}
 
 	// If name isn't a machine ID, try it as a unit instead
 	if ms == nil {
 		units, err := c.Units(name)
 
 		if err != nil {
-			return err
+			return nil, err
 		}
 
 		machID, err := c.findUnit(units[0])
 
 		if err != nil {
-			return err
+			return nil, err
 		}
 
 		ms, err = c.machineState(machID)
 
 		if err != nil || ms == nil {
-			return err
+			return nil, err
 		}
 	}
 
 	addr := ms.PublicIP
 
 	if tun := getTunnelFlag(); tun != "" {
-		sshClient, err = ssh.NewTunnelledSSHClient("core", tun, addr, getChecker(), false, timeout)
-	} else {
-		sshClient, err = ssh.NewSSHClient("core", addr, getChecker(), false, timeout)
-	}
-	if err != nil {
-		return err
+		return ssh.NewTunnelledSSHClient("core", tun, addr, getChecker(), false, timeout)
 	}
+	return ssh.NewSSHClient("core", addr, getChecker(), false, timeout)
 
-	defer sshClient.Close()
-	err = ssh.Shell(sshClient)
-	return err
 }
 
 // runCommand will attempt to run a command on a given machine. It will attempt

deisctl/client/client.go

@@ -241,16 +241,45 @@ Usage:
 func (c *Client) SSH(argv []string) error {
 	usage := `Open an interactive shell on a machine in the cluster given a unit or machine id.
 
+If an optional <command> is provided, that command is run remotely, and the results returned.
+
 Usage:
-  deisctl ssh <target>
+  deisctl ssh <target> [<command>...]
 `
 	// parse command-line arguments
-	args, err := docopt.Parse(usage, argv, true, "", false)
+	args, err := docopt.Parse(usage, argv, true, "", true)
 	if err != nil {
 		return err
 	}
 
-	return cmd.SSH(args["<target>"].(string), c.Backend)
+	var vargs []string
+	if v, ok := args["<command>"]; ok {
+		vargs = v.([]string)
+	}
+
+	return cmd.SSH(args["<target>"].(string), vargs, c.Backend)
+}
+
+func (c *Client) Dock(argv []string) error {
+	usage := `Connect to the named docker container and run commands on it.
+
+This is equivalent to running 'docker exec -it <target> <command>'.
+
+Usage:
+  deisctl dock <target> [<command>...]
+`
+	// parse command-line arguments
+	args, err := docopt.Parse(usage, argv, true, "", true)
+	if err != nil {
+		return err
+	}
+
+	var vargs []string
+	if v, ok := args["<command>"]; ok {
+		vargs = v.([]string)
+	}
+
+	return cmd.Dock(args["<target>"].(string), vargs, c.Backend)
 }
 
 // Start activates the specified components.

deisctl/cmd/cmd.go

@@ -464,10 +464,24 @@ func RefreshUnits(dir, tag, url string) error {
 }
 
 // SSH opens an interactive shell on a machine in the cluster
-func SSH(target string, b backend.Backend) error {
-	if err := b.SSH(target); err != nil {
-		return err
+func SSH(target string, cmd []string, b backend.Backend) error {
+
+	if len(cmd) > 0 {
+		return b.SSHExec(target, strings.Join(cmd, " "))
 	}
 
-	return nil
+	return b.SSH(target)
+}
+
+// Dock connects to the appropriate host and runs 'docker exec -it'.
+func Dock(target string, cmd []string, b backend.Backend) error {
+
+	c := "sh"
+	if len(cmd) > 0 {
+		c = strings.Join(cmd, " ")
+	}
+
+	execit := fmt.Sprintf("docker exec -it %s %s", target, c)
+
+	return b.SSHExec(target, execit)
 }

deisctl/cmd/cmd_test.go

@@ -12,6 +12,7 @@ import (
 	"sync"
 	"testing"
 
+	"github.com/deis/deis/deisctl/backend"
 	"github.com/deis/deis/deisctl/units"
 )
 
@@ -69,6 +70,14 @@ func (backend *backendStub) SSH(target string) error {
 	}
 	return errors.New("Error")
 }
+func (backend *backendStub) SSHExec(target, command string) error {
+	if target == "controller" && command == "sh" {
+		return nil
+	}
+	return errors.New("Error")
+}
+
+var _ backend.Backend = &backendStub{}
 
 func fakeCheckKeys() error {
 	return nil
@@ -332,7 +341,17 @@ func TestSSH(t *testing.T) {
 	t.Parallel()
 
 	b := backendStub{}
-	err := SSH("controller", &b)
+	err := SSH("controller", []string{}, &b)
+
+	if err != nil {
+		t.Error(err)
+	}
+}
+func TestSSHExec(t *testing.T) {
+	t.Parallel()
+
+	b := backendStub{}
+	err := SSH("controller", []string{"sh"}, &b)
 
 	if err != nil {
 		t.Error(err)
@@ -343,7 +362,7 @@ func TestSSHError(t *testing.T) {
 	t.Parallel()
 
 	b := backendStub{}
-	err := SSH("registry", &b)
+	err := SSH("registry", []string{}, &b)
 
 	if err == nil {
 		t.Error("Error expected")

deisctl/deisctl.go

@@ -112,6 +112,8 @@ Options:
 		err = c.RefreshUnits(argv)
 	case "ssh":
 		err = c.SSH(argv)
+	case "dock":
+		err = c.Dock(argv)
 	case "help":
 		fmt.Print(usage)
 		return 0

docs/troubleshooting_deis/index.rst

@@ -24,6 +24,33 @@ To open a interactive shell on a machine in your cluster:
 
     $ deisctl ssh <unit>
 
+For example, to open a shell session on the machine that is running Controller,
+you can run this:
+
+.. code-block:: console
+
+    $ deisctl ssh controller
+
+You can execute just a single command instead of opening a shell:
+
+.. code-block:: console
+
+    $ deisctl ssh <unit> <command>
+
+You can also connect directly to the Docker instance of that unit:
+
+.. code-block:: console
+
+    $ deisctl dock <unit> <command>
+
+For example, to start a Bash session on the Builder Docker container, you can
+run the following command:
+
+.. code-block:: console
+
+    $ deisctl dock builder bash`
+
+
 Troubleshooting etcd
 --------------------