如何让Bottle在500响应中输出错误信息？模板缺失调试求助

I’ve run into this exact frustrating quirk with Bottle before—nothing’s worse than debugging a missing template when you can’t even tell which one is missing! Let’s walk through the most reliable fixes:

• Check for custom error handlers swallowing the message
  If you’ve added any global error handlers or try-except blocks in your code that catch TemplateError, they might be suppressing the full error details. Look for code like this:

  try:
      # Route code that renders a template
  except TemplateError:
      return "Something went wrong"  # This hides the actual template name!
  

  Replace these with handlers that preserve the exception message, or remove them temporarily to see if the full error appears.

• Add an explicit TemplateError handler to force detail display
  Create a dedicated error handler to ensure you see the exact missing template name in both the console and browser:

  from bottle import Bottle, TemplateError, debug
  
  app = Bottle()
  debug(True)
  
  @app.error(TemplateError)
  def show_template_error(error):
      # Print full error to console
      print(f"Full Template Error: {str(error)}")
      # Return detailed response to the webpage
      return f"<h1>Template Not Found</h1><p>{str(error)}</p>", 500
  
  # Your route definitions here...
  

  This will override Bottle’s default error handling for template issues and show you the complete formatted message.

• Upgrade your Bottle version
  This was a known bug in older Bottle releases (especially pre-0.12 versions). Since you’re using Python 2.7, install the latest compatible version to fix exception formatting issues:

  pip install --upgrade bottle==0.12.23
  

  This version resolves several edge cases where the template name wasn’t being included in the error message.

• Inspect the exception directly in your route
  If all else fails, temporarily catch the exception in your route code to verify the template name is actually present in the exception:

  @app.route('/your-target-route')
  def your_route():
      try:
          return template('your-template-name')
      except TemplateError as e:
          print(f"Exception message: {str(e)}")
          print(f"Exception args: {e.args}")
          raise  # Re-raise to let Bottle handle it normally afterward
  

  If the template name shows up here but not in the default error display, it confirms the issue is with Bottle’s default error rendering logic.

Once you’ve identified the missing template, double-check its location: Bottle looks in the views directory by default, so ensure the file exists there or specify the full path in the template() call.

内容的提问来源于stack exchange，提问作者l0b0