feat: set server type explicitly (#36)

- **CLI**: New flag `--server-type` that overrides the `--architecture`
flag and allows users to specify the server type they want
- **Lib**: New field in `UploadOptions`: `ServerType *hcloud.ServerType`
that overrides the `Architecture` field and allows users to specify the
server type they want

Closes #30

cmd/upload.go

@@ -17,6 +17,7 @@ const (
 	uploadFlagImagePath    = "image-path"
 	uploadFlagCompression  = "compression"
 	uploadFlagArchitecture = "architecture"
+	uploadFlagServerType   = "server-type"
 	uploadFlagDescription  = "description"
 	uploadFlagLabels       = "labels"
 )
@@ -43,12 +44,12 @@ This does cost a bit of money for the server.`,
 		imagePathString, _ := cmd.Flags().GetString(uploadFlagImagePath)
 		imageCompression, _ := cmd.Flags().GetString(uploadFlagCompression)
 		architecture, _ := cmd.Flags().GetString(uploadFlagArchitecture)
+		serverType, _ := cmd.Flags().GetString(uploadFlagServerType)
 		description, _ := cmd.Flags().GetString(uploadFlagDescription)
 		labels, _ := cmd.Flags().GetStringToString(uploadFlagLabels)
 
 		options := hcloudimages.UploadOptions{
 			ImageCompression: hcloudimages.Compression(imageCompression),
-			Architecture:     hcloud.Architecture(architecture),
 			Description:      hcloud.Ptr(description),
 			Labels:           labels,
 		}
@@ -69,6 +70,12 @@ This does cost a bit of money for the server.`,
 			options.ImageReader = imageFile
 		}
 
+		if architecture != "" {
+			options.Architecture = hcloud.Architecture(architecture)
+		} else if serverType != "" {
+			options.ServerType = &hcloud.ServerType{Name: serverType}
+		}
+
 		image, err := client.Upload(ctx, options)
 		if err != nil {
 			return fmt.Errorf("failed to upload the image: %w", err)
@@ -99,7 +106,12 @@ func init() {
 		uploadFlagArchitecture,
 		cobra.FixedCompletions([]string{string(hcloud.ArchitectureX86), string(hcloud.ArchitectureARM)}, cobra.ShellCompDirectiveNoFileComp),
 	)
-	_ = uploadCmd.MarkFlagRequired(uploadFlagArchitecture)
+
+	uploadCmd.Flags().String(uploadFlagServerType, "", "Explicitly use this server type to generate the image. Mutually exclusive with --architecture.")
+
+	// Only one of them needs to be set
+	uploadCmd.MarkFlagsOneRequired(uploadFlagArchitecture, uploadFlagServerType)
+	uploadCmd.MarkFlagsMutuallyExclusive(uploadFlagArchitecture, uploadFlagServerType)
 
 	uploadCmd.Flags().String(uploadFlagDescription, "", "Description for the resulting image")
 

hcloudimages/client.go

@@ -65,8 +65,17 @@ type UploadOptions struct {
 	// used with [hcloud.ArchitectureX86] or [hcloud.ArchitectureARM] servers.
 	//
 	// Internally this decides what server type is used for the temporary server.
+	//
+	// Optional if [UploadOptions.ServerType] is set.
 	Architecture hcloud.Architecture
 
+	// ServerType can be optionally set to override the default server type for the architecture.
+	// Situations where this makes sense:
+	//
+	//   - Your image is larger than the root disk of the default server types.
+	//   - The default server type is no longer available, or not temporarily out of stock.
+	ServerType *hcloud.ServerType
+
 	// Description is an optional description that the resulting image (snapshot) will have. There is no way to
 	// select images by its description, you should use Labels if you need  to identify your image later.
 	Description *string
@@ -159,9 +168,15 @@ func (s *Client) Upload(ctx context.Context, options UploadOptions) (*hcloud.Ima
 
 	// 2. Create Server
 	logger.InfoContext(ctx, "# Step 2: Creating Server")
-	serverType, ok := serverTypePerArchitecture[options.Architecture]
+	var serverType *hcloud.ServerType
-	if !ok {
+	if options.ServerType != nil {
-		return nil, fmt.Errorf("unknown architecture %q, valid options: %q, %q", options.Architecture, hcloud.ArchitectureX86, hcloud.ArchitectureARM)
+		serverType = options.ServerType
+	} else {
+		var ok bool
+		serverType, ok = serverTypePerArchitecture[options.Architecture]
+		if !ok {
+			return nil, fmt.Errorf("unknown architecture %q, valid options: %q, %q", options.Architecture, hcloud.ArchitectureX86, hcloud.ArchitectureARM)
+		}
 	}
 
 	logger.DebugContext(ctx, "creating server with config",