common-lisp: tutorial six code

common-lisp/rpc-client.lisp

@@ -0,0 +1,46 @@
+#!/bin/sh
+
+sbcl --noinform --noprint <<EOF
+
+(ql:quickload :cl-bunny.examples)
+(ql:quickload :nibbles)
+
+(in-package :cl-bunny.examples)
+
+(defun int64-to-octets(val)
+  (let ((obuffer (fast-io:make-output-buffer)))
+    (fast-io:write64-be val obuffer)
+    (fast-io:finish-output-buffer obuffer)))
+
+(defun start-client (n)
+  (with-connection ("amqp://")
+    (with-channel ()
+      (let ((x (exchange.default))
+            (server-queue "rpc_queue")
+            (reply-queue (queue.declare :auto-delete t))
+            (lock (bt:make-lock))
+            (condition (bt:make-condition-variable))
+            (result nil))
+        (format t " [x] Requesting fib(~a)~%" n)
+        (bt:with-lock-held (lock)
+          (subscribe reply-queue (lambda (message)
+                                    (bt:with-lock-held (lock)
+                                      (setf result (nibbles:sb64ref/be (message-body message) 0))
+                                      (bt:condition-notify condition))))
+          (publish x
+                   (int64-to-octets n)
+                   :routing-key server-queue
+                   :properties (list :correlation-id (format nil "~a~a~a" (random 100) (random 100) (random 100))
+                                     :reply-to reply-queue))
+          (bt:condition-wait condition lock)
+          (format t " [.] Got ~a~%" result)
+          result)))))
+
+(start-client 0)
+(start-client 1)
+(start-client 22)
+(start-client 33)
+(start-client 44)
+(start-client 55)
+
+EOF

common-lisp/rpc-server.lisp

@@ -0,0 +1,54 @@
+#!/bin/sh
+
+sbcl --noinform --noprint <<EOF
+
+(ql:quickload :cl-bunny.examples)
+(ql:quickload :nibbles)
+
+(in-package :cl-bunny.examples)
+
+(defun int64-to-octets(val)
+  (let ((obuffer (fast-io:make-output-buffer)))
+    (fast-io:write64-be val obuffer)
+    (fast-io:finish-output-buffer obuffer)))
+
+;; http://www.cliki.net/fibonacci
+(defun fibonacci (n)
+  "Successive squaring method from SICP"
+  (check-type n (integer 0 *))
+  (labels ((fib-aux (a b p q count)
+             (cond ((= count 0) b)
+                   ((evenp count)
+                    (fib-aux a
+                             b
+                             (+ (* p p) (* q q))
+                             (+ (* q q) (* 2 p q))
+                             (/ count 2)))
+                   (t (fib-aux (+ (* b q) (* a q) (* a p))
+                               (+ (* b p) (* a q))
+                               p
+                               q
+                               (- count 1))))))
+    (fib-aux 1 0 0 1 n)))
+
+(with-connection ()
+  (with-channel ()
+    (let ((x (exchange.default))
+          (q (queue.declare :name "rpc_queue" :auto-delete t)))
+      (format t " [x] Awaiting RPC requests~%")
+      (handler-case
+          (progn
+            (subscribe q (lambda (message)
+                            (let* ((n (nibbles:sb64ref/be (message-body message) 0))
+                                   (r (fibonacci n)))
+                              (format t " [.] fib(~a)~%" r)
+                              (publish x
+                                       (int64-to-octets r)
+                                       :routing-key (message-reply-to message)
+                                       :properties (list :correlation-id (message-correlation-id message)))))
+                       :type :sync)
+            (consume))
+        (sb-sys:interactive-interrupt ()
+          (sb-ext:exit))))))
+
+EOF