Add support for builds using rescue mode

builder/hcloud/config.go

@@ -35,6 +35,8 @@ type Config struct {
 	UserDataFile string   `mapstructure:"user_data_file"`
 	SSHKeys      []string `mapstructure:"ssh_keys"`
 
+	RescueMode string `mapstructure:"rescue"`
+
 	ctx interpolate.Context
 }
 

builder/hcloud/step_create_server.go

@@ -68,11 +68,12 @@ func (s *stepCreateServer) Run(ctx context.Context, state multistep.StateBag) mu
 	state.Put("server_id", serverCreateResult.Server.ID)
 
 	_, errCh := client.Action.WatchProgress(context.TODO(), serverCreateResult.Action)
+watch:
 	for {
 		select {
 		case err1 := <-errCh:
 			if err1 == nil {
-				return multistep.ActionContinue
+				break watch
 			} else {
 				err := fmt.Errorf("Error creating server: %s", err)
 				state.Put("error", err)
@@ -82,6 +83,17 @@ func (s *stepCreateServer) Run(ctx context.Context, state multistep.StateBag) mu
 
 		}
 	}
+
+	if c.RescueMode != "" {
+		if err := setRescue(ctx, client, serverCreateResult.Server, c.RescueMode, sshKeys); err != nil {
+			err := fmt.Errorf("Error enabling rescue mode: %s", err)
+			state.Put("error", err)
+			ui.Error(err.Error())
+			return multistep.ActionHalt
+		}
+	}
+
+	return multistep.ActionContinue
 }
 
 func (s *stepCreateServer) Cleanup(state multistep.StateBag) {
@@ -101,3 +113,48 @@ func (s *stepCreateServer) Cleanup(state multistep.StateBag) {
 			"Error destroying server. Please destroy it manually: %s", err))
 	}
 }
+
+func setRescue(ctx context.Context, client *hcloud.Client, server *hcloud.Server, rescue string, sshKeys []*hcloud.SSHKey) error {
+	rescueChanged := false
+	if server.RescueEnabled {
+		rescueChanged = true
+		action, _, err := client.Server.DisableRescue(ctx, server)
+		if err != nil {
+			return err
+		}
+		if err := waitForServerAction(ctx, client, action, server); err != nil {
+			return err
+		}
+	}
+	if rescue != "" {
+		rescueChanged = true
+		res, _, err := client.Server.EnableRescue(ctx, server, hcloud.ServerEnableRescueOpts{
+			Type:    hcloud.ServerRescueType(rescue),
+			SSHKeys: sshKeys,
+		})
+		if err != nil {
+			return err
+		}
+		if err := waitForServerAction(ctx, client, res.Action, server); err != nil {
+			return err
+		}
+	}
+	if rescueChanged {
+		action, _, err := client.Server.Reset(ctx, server)
+		if err != nil {
+			return err
+		}
+		if err := waitForServerAction(ctx, client, action, server); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func waitForServerAction(ctx context.Context, client *hcloud.Client, action *hcloud.Action, server *hcloud.Server) error {
+	_, errCh := client.Action.WatchProgress(ctx, action)
+	if err := <-errCh; err != nil {
+		return err
+	}
+	return nil
+}

website/source/docs/builders/hetzner-cloud.html.md

@@ -72,6 +72,8 @@ builder.
 -   `ssh_keys` (array of strings) - List of SSH keys by name or id to be added
     to image on launch.
 
+-   `rescue` (string) - Enable and boot in to the specified rescue system. This enables simple installation of custom operating systems. `linux64` `linux32` or `freebsd64`    
+
 ## Basic Example
 
 Here is a basic example. It is completely valid as soon as you enter your own