passepartout/harness/communication.org

Communication Protocol (communication.lisp)

• Overview
• Implementation
  • Package Context
  • Actuator Registry
  • Message Framing
  • Handshake Logic
  • Structural Validation
• Test Suite

Overview

The communication.lisp module defines the low-level transport and framing logic for OpenCortex stimuli.

Implementation

Package Context

(in-package :opencortex)

Actuator Registry

(defvar *actuator-registry* (make-hash-table :test 'equalp)
  "Global registry mapping target keywords to their physical actuator functions.")

(defun register-actuator (name fn) 
  "Registers an actuator function. Actuators receive: (ACTION CONTEXT)."
  (let ((key (if (keywordp name) name (intern (string-upcase (string name)) :keyword))))
    (setf (gethash key *actuator-registry*) fn)))

Message Framing

(defun sanitize-protocol-message (msg)
  "Recursively strips non-serializable objects from a protocol plist."
  (if (and msg (listp msg))
      (let ((clean nil))
        (loop for (k v) on msg by #'cddr
              do (unless (member k '(:reply-stream :socket :stream))
                   (push k clean)
                   (push (if (listp v) (sanitize-protocol-message v) v) clean)))
        (nreverse clean))
      msg))

(defun frame-message (msg)
  "Serializes a message plist and prefixes it with a 6-character hex length."
  (let* ((sanitized (sanitize-protocol-message msg))
         (payload (let ((*print-pretty* nil) (*read-eval* nil)) (format nil "~s" sanitized)))
         (len (length payload)))
    (format nil "~6,'0x~a" len payload)))

(defun read-framed-message (stream)
  "Reads a hex-length prefixed S-expression from the stream securely."
  (let ((length-buffer (make-string 6)))
    (handler-case
        (progn
          (loop for char = (peek-char nil stream nil :eof)
                while (and (not (eq char :eof)) (member char '(#\Space #\Newline #\Tab #\Return)))
                do (read-char stream))
          (let ((count (read-sequence length-buffer stream)))
            (if (< count 6)
                :eof
                (let ((len (ignore-errors (parse-integer length-buffer :radix 16))))
                  (if (not len)
                      :error
                      (let ((msg-buffer (make-string len)))
                        (read-sequence msg-buffer stream)
                        (let ((*read-eval* nil))
                          (handler-case (read-from-string msg-buffer)
                            (error () :error)))))))))
      (error () :error))))

Handshake Logic

(defun make-hello-message (version)
  "Constructs the standard HELLO handshake message."
  (list :TYPE :EVENT 
        :PAYLOAD (list :ACTION :handshake 
                       :VERSION version 
                       :CAPABILITIES '(:AUTH :ORG-AST))))

Structural Validation

(in-package :opencortex)

(defun validate-communication-protocol-schema (msg)
  "Strict structural validation for incoming protocol messages."
  (unless (listp msg) (error "Message must be a plist"))
  (let ((type (proto-get msg :type)))
    (unless (member type '(:REQUEST :EVENT :RESPONSE :LOG :STATUS))
      (error "Invalid message type '~a'" type))
    t))

Test Suite

(defpackage :opencortex-communication-tests
  (:use :cl :fiveam :opencortex)
  (:export #:communication-protocol-suite))
(in-package :opencortex-communication-tests)

(def-suite communication-protocol-suite :description "Communication Protocol Suite
(in-suite communication-protocol-suite)

(test test-framing
  (let* ((msg '(:type :EVENT :payload (:action :handshake)))
         (framed (frame-message msg)))
    (is (string= "00002C" (string-upcase (subseq framed 0 6))))))