Class: A2A::Plugins::ExampleMiddleware

Inherits:
A2A::Plugin::MiddlewarePlugin show all
Defined in:
lib/a2a/plugins/example_middleware.rb

Instance Attribute Summary

Attributes inherited from A2A::Plugin::Base

#config, #logger

Instance Method Summary collapse

Methods inherited from A2A::Plugin::Base

dependencies, depends_on, inherited, #initialize, plugin_type

Constructor Details

This class inherits a constructor from A2A::Plugin::Base

Instance Method Details

#call(request, next_middleware) ⇒ Object

Process request through middleware

Parameters:

  • request (Hash) —

    Request data

  • next_middleware (Proc) —

    Next middleware in chain

Returns:

  • (Object) —

    Response



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# File 'lib/a2a/plugins/example_middleware.rb', line 21

def call(request, next_middleware)
  start_time = Time.now

  logger&.info("Example Middleware: Processing request #{request[:id]}")

  # Pre-processing
  request = preprocess_request(request)

  begin
    # Call next middleware in chain
    response = next_middleware.call(request)

    # Post-processing
    response = postprocess_response(response, request)

    # Log success
    duration = Time.now - start_time
    logger&.info("Example Middleware: Request completed in #{duration.round(3)}s")

    response
  rescue StandardError => e
    # Error handling
    duration = Time.now - start_time
    logger&.error("Example Middleware: Request failed after #{duration.round(3)}s: #{e.message}")

    # Execute error hooks
    A2A::Plugin.execute_hooks(A2A::Plugin::Events::REQUEST_ERROR, e, request)

    raise
  end
end

#cleanup ⇒ Object (private) 



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# File 'lib/a2a/plugins/example_middleware.rb', line 73

def cleanup
  logger&.info("Example Middleware plugin cleaned up (processed #{@request_counter} requests, #{@error_counter} errors)")
end

#middleware_name ⇒ Object

Middleware name for identification



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# File 'lib/a2a/plugins/example_middleware.rb', line 13

def middleware_name
  "example"
end

#postprocess_response(response, request) ⇒ Object (private) 



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# File 'lib/a2a/plugins/example_middleware.rb', line 93

def postprocess_response(response, request)
  # Add processing time to response metadata
  if request[:processing] && request[:processing][:middleware_start]
    processing_time = Time.now.to_f - request[:processing][:middleware_start]

    if response.is_a?(Hash)
      response[:metadata] ||= {}
      response[:metadata][:processing_time] = processing_time
    end
  end

  response
end

#preprocess_request(request) ⇒ Object (private) 



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# File 'lib/a2a/plugins/example_middleware.rb', line 77

def preprocess_request(request)
  @request_counter += 1

  # Add request ID if not present
  request[:id] ||= SecureRandom.uuid

  # Add processing metadata
  request[:processing] ||= {}
  request[:processing][:middleware_start] = Time.now.to_f

  # Validate request structure
  validate_request_structure(request)

  request
end

#register_hooks(plugin_manager) ⇒ Object

Register hooks for this plugin



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# File 'lib/a2a/plugins/example_middleware.rb', line 54

def register_hooks(plugin_manager)
  plugin_manager.add_hook(A2A::Plugin::Events::BEFORE_REQUEST, priority: 10) do |request|
    logger&.debug("Example Middleware: Adding request metadata")
    request[:middleware_metadata] ||= {}
    request[:middleware_metadata][:example] = {
      processed_at: Time.now.iso8601,
      version: "1.0.0"
    }
  end
end

#setup ⇒ Object (private) 



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# File 'lib/a2a/plugins/example_middleware.rb', line 67

def setup
  @request_counter = 0
  @error_counter = 0
  logger&.info("Example Middleware plugin initialized")
end

#validate_request_structure(request) ⇒ Object (private)

Raises:



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# File 'lib/a2a/plugins/example_middleware.rb', line 107

def validate_request_structure(request)
  raise A2A::Errors::InvalidRequest, "Request must be a hash" unless request.is_a?(Hash)

  return if request[:method]

  raise A2A::Errors::InvalidRequest, "Request must have a method"

  # Additional validation can be added here
end