Output new ServerID after publishing (#359)

When using `mcp-publisher publish ...`, output the new server `ID` if
publishing is successful.

## Motivation and Context

It's useful to know this during testing. It means that you don't have to
go and search for the new server ID afterwards. Once we have the
`v0/servers/{name}/{version}`, I think we could consider removing this
again.

## How Has This Been Tested?

I've been using this while I test publishing to locally running
registries.

## Breaking Changes

none

## Types of changes
<!-- What types of changes does your code introduce? Put an `x` in all
the boxes that apply: -->
- [ ] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update

## Checklist
<!-- Go over all the following points, and put an `x` in all the boxes
that apply. -->
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [ ] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed

cmd/publisher/commands/publish.go

@@ -65,26 +65,31 @@ func PublishCommand(args []string) error {
 
 	// Publish to registry
 	_, _ = fmt.Fprintf(os.Stdout, "Publishing to %s...\n", registryURL)
-	if err := publishToRegistry(registryURL, serverData, token); err != nil {
+	response, err := publishToRegistry(registryURL, serverData, token)
+	if err != nil {
 		return fmt.Errorf("publish failed: %w", err)
 	}
 
 	_, _ = fmt.Fprintln(os.Stdout, "✓ Successfully published")
+	if serverID := response.GetID(); serverID != "" {
+		_, _ = fmt.Fprintf(os.Stdout, "✓ Server Id %s", serverID)
+	}
+
 	return nil
 }
 
-func publishToRegistry(registryURL string, serverData []byte, token string) error {
+func publishToRegistry(registryURL string, serverData []byte, token string) (*apiv0.ServerJSON, error) {
 	// Parse the server JSON data
 	var serverJSON apiv0.ServerJSON
 	err := json.Unmarshal(serverData, &serverJSON)
 	if err != nil {
-		return fmt.Errorf("error parsing server.json file: %w", err)
+		return nil, fmt.Errorf("error parsing server.json file: %w", err)
 	}
 
 	// Convert to JSON
 	jsonData, err := json.Marshal(serverJSON)
 	if err != nil {
-		return fmt.Errorf("error serializing request: %w", err)
+		return nil, fmt.Errorf("error serializing request: %w", err)
 	}
 
 	// Ensure URL ends with the publish endpoint
@@ -96,7 +101,7 @@ func publishToRegistry(registryURL string, serverData []byte, token string) erro
 	// Create and send request
 	req, err := http.NewRequestWithContext(context.Background(), http.MethodPost, publishURL, bytes.NewBuffer(jsonData))
 	if err != nil {
-		return fmt.Errorf("error creating request: %w", err)
+		return nil, fmt.Errorf("error creating request: %w", err)
 	}
 	req.Header.Set("Content-Type", "application/json")
 	req.Header.Set("Authorization", "Bearer "+token)
@@ -104,19 +109,23 @@ func publishToRegistry(registryURL string, serverData []byte, token string) erro
 	client := &http.Client{}
 	resp, err := client.Do(req)
 	if err != nil {
-		return fmt.Errorf("error sending request: %w", err)
+		return nil, fmt.Errorf("error sending request: %w", err)
 	}
 	defer resp.Body.Close()
 
 	// Read response
 	body, err := io.ReadAll(resp.Body)
 	if err != nil {
-		return fmt.Errorf("error reading response: %w", err)
+		return nil, fmt.Errorf("error reading response: %w", err)
 	}
 
 	if resp.StatusCode != http.StatusCreated && resp.StatusCode != http.StatusOK {
-		return fmt.Errorf("server returned status %d: %s", resp.StatusCode, body)
+		return nil, fmt.Errorf("server returned status %d: %s", resp.StatusCode, body)
 	}
 
-	return nil
+	if err := json.Unmarshal(body, &serverJSON); err != nil {
+		return nil, err
+	}
+
+	return &serverJSON, nil
 }

pkg/api/v0/types.go

@@ -44,3 +44,10 @@ type Metadata struct {
 	NextCursor string `json:"next_cursor,omitempty"`
 	Count      int    `json:"count"`
 }
+
+func (s *ServerJSON) GetID() string {
+	if s.Meta != nil && s.Meta.Official != nil {
+		return s.Meta.Official.ID
+	}
+	return ""
+}