How to Implement Hierarchical Templates with Automatic Reloading in Go App Engine?

Go AppEngine: Hierarchical Templates with Automatic Reload

Question:

How can I structure templates in a Go AppEngine application to achieve:

• Hierarchical organization
• Compatibility with HTML tools
• Automatic template reloading on the dev server

Potential Challenges:

• Template.ParseGlob() doesn't recurse
• Uploading raw text templates is discouraged for performance reasons

Solution:

Organize your Go AppEngine project with a modular structure, where each package owns a URL prefix and contains its own templates. This approach allows you to maintain a consistent base template and extend it within each package.

Example Project Structure:

|-- app.yaml
|-- app
|   +-- http.go
|-- templates
|   +-- base.html
+-- github.com
    +-- storeski
        +-- appengine
            +-- products
            |   +-- http.go
            |   +-- templates
            |       |-- list.html
            |       +-- detail.html
            +-- account
                |-- http.go
                +-- templates
                    |-- overview.html
                    |-- notifications.html 

In each package's http.go file, register handlers for the URLs it owns. For example, the products package would handle URLs starting with /products.

Within each package, store templates in a "templates" subdirectory, and create a base template (e.g., templates/base.html) that other templates can extend.

To enable automatic template reloading on the dev server, implement a custom function to watch for changes in the templates directory:

func watchTemplates() {
  ticker := time.NewTicker(1 * time.Second)
  for range ticker.C {
    if err := parseTemplates(); err != nil {
      log.Printf("Error parsing templates: %v", err)
    }
  }
}

In your main package, call watchTemplates() to periodically check for template changes and reload them. This ensures that updates to templates are automatically reflected in your application.

The above is the detailed content of How to Implement Hierarchical Templates with Automatic Reloading in Go App Engine?. For more information, please follow other related articles on the PHP Chinese website!