add ssh_keys config to hcloud builder

builder/hcloud/config.go

@@ -30,9 +30,10 @@ type Config struct {
 	ServerType string `mapstructure:"server_type"`
 	Image      string `mapstructure:"image"`
 
-	SnapshotName string `mapstructure:"snapshot_name"`
-	UserData     string `mapstructure:"user_data"`
-	UserDataFile string `mapstructure:"user_data_file"`
+	SnapshotName string   `mapstructure:"snapshot_name"`
+	UserData     string   `mapstructure:"user_data"`
+	UserDataFile string   `mapstructure:"user_data_file"`
+	SSHKeys      []string `mapstructure:"ssh_keys"`
 
 	ctx interpolate.Context
 }

builder/hcloud/step_create_server.go

@@ -15,7 +15,7 @@ type stepCreateServer struct {
 	serverId int
 }
 
-func (s *stepCreateServer) Run(_ context.Context, state multistep.StateBag) multistep.StepAction {
+func (s *stepCreateServer) Run(ctx context.Context, state multistep.StateBag) multistep.StepAction {
 	client := state.Get("hcloudClient").(*hcloud.Client)
 	ui := state.Get("ui").(packer.Ui)
 	c := state.Get("config").(*Config)
@@ -35,11 +35,22 @@ func (s *stepCreateServer) Run(_ context.Context, state multistep.StateBag) mult
 		userData = string(contents)
 	}
 
+	sshKeys := []*hcloud.SSHKey{{ID: sshKeyId}}
+	for _, k := range c.SSHKeys {
+		sshKey, _, err := client.SSHKey.Get(ctx, k)
+		if err != nil {
+			ui.Error(err.Error())
+			state.Put("error", fmt.Errorf("Error fetching SSH key: %s", err))
+			return multistep.ActionHalt
+		}
+		sshKeys = append(sshKeys, sshKey)
+	}
+
 	serverCreateResult, _, err := client.Server.Create(context.TODO(), hcloud.ServerCreateOpts{
 		Name:       c.ServerName,
 		ServerType: &hcloud.ServerType{Name: c.ServerType},
 		Image:      &hcloud.Image{Name: c.Image},
-		SSHKeys:    []*hcloud.SSHKey{{ID: sshKeyId}},
+		SSHKeys:    sshKeys,
 		Location:   &hcloud.Location{Name: c.Location},
 		UserData:   userData,
 	})

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

@@ -69,6 +69,9 @@ builder.
 -   `user_data_file` (string) - Path to a file that will be used for the user
     data when launching the server.
 
+-   `ssh_keys` (array of strings) - List of SSH keys by name or id to be added
+    to image on launch.
+
 ## Basic Example
 
 Here is a basic example. It is completely valid as soon as you enter your own