Module: Prosody::ErrorClassification

Included in:
EventHandler
Defined in:
lib/prosody/handler.rb,
sig/handler.rbs

Overview

Mixin providing class-level methods to wrap instance methods so that specified exceptions are re-wrapped as PermanentError or TransientError.

Instance Method Summary collapse

Instance Method Details

#permanent(method_name, *exception_classes) ⇒ void

This method returns an undefined value.

Wraps the given instance method so that specified exception types are caught and re-raised as Prosody::PermanentError.

Parameters:

  • method_name —

    the name of the method to wrap

  • exception_classes —

    one or more Exception subclasses to catch

Raises:

  • (ArgumentError) —

    if no exception classes given or invalid

  • (NameError) —

    if method_name is not defined



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# File 'lib/prosody/handler.rb', line 75

def permanent(method_name, *exception_classes)
  wrap_errors(method_name, exception_classes, PermanentError)
end

#transient(method_name, *exception_classes) ⇒ void

This method returns an undefined value.

Wraps the given instance method so that specified exception types are caught and re-raised as Prosody::TransientError.

Parameters:

  • method_name —

    the name of the method to wrap

  • exception_classes —

    one or more Exception subclasses to catch

Raises:

  • (ArgumentError) —

    if no exception classes given or invalid

  • (NameError) —

    if method_name is not defined



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# File 'lib/prosody/handler.rb', line 87

def transient(method_name, *exception_classes)
  wrap_errors(method_name, exception_classes, TransientError)
end

#wrap_errors(method_name, exception_classes, error_class) ⇒ void

This method returns an undefined value.

Core implementation: redefines method_name to catch listed exceptions and re-raise them as the specified error class.

Parameters:

  • method_name —

    the method to wrap

  • exception_classes —

    exceptions to catch

  • error_class —

    the error class to wrap caught exceptions in



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# File 'lib/prosody/handler.rb', line 100

def wrap_errors(method_name, exception_classes, error_class)
  # Must specify at least one exception class
  if exception_classes.empty?
    raise ArgumentError, "At least one exception class must be provided"
  end

  # Ensure the method exists (in this class or its ancestors)
  unless method_defined?(method_name)
    raise NameError, "Method `#{method_name}` is not defined"
  end

  # Build a prepended wrapper module
  wrapper = Module.new do
    define_method(method_name) do |*args, &block|
      super(*args, &block)
    rescue *exception_classes => e
      # The new exception's #cause will be set automatically
      Kernel.raise error_class.new(e.message)
    end
  end
  wrapper.instance_variable_set(:@prosody_error_wrapper, true)

  prepend wrapper
end