peer connections and json

router

@@ -2,19 +2,81 @@
 #lang racket
 ; vim:syntax=racket
 
-(require "iputil.rkt")
+(require json
+         "iputil.rkt"
+         "unix-socket.rkt")
+
+;; info : Peer
+;; sock-in : Input-Port
+;; sock-out : Output-Port
+(struct peer-conn
+  [info sock-in sock-out]
+  #:transparent)
+
+;; Str [Listof Peer-Conn] -> [-> Void]
+;; --
+;; runs router logic given peer connections. returns thunk that, when called, aborts the
+;; router.
+(define (run-router/conns ans peer-conns)
+  (define mail
+    (make-channel))
+
+  (define peer-threads
+    (for/list ([pc (in-list peer-conns)])
+      (match-define (peer-conn peer sock-in sock-out) pc)
+      (thread (λ ()
+                (define buf (make-bytes 65536))
+                (let loop ()
+                  (define len (read-bytes-avail! buf sock-in))
+                  (define jsexpr (bytes->jsexpr (subbytes buf 0 len)))
+                  (channel-put mail (list peer jsexpr))
+                  (loop))))))
+
+  (define (loop)
+    (match-define (list peer data) (channel-get mail))
+    (printf "from ~a:\n~s\n" peer data)
+    (loop))
+
+  (define loop-thread
+    (thread loop))
+
+  (λ ()
+    (for-each break-thread
+              (cons loop-thread
+                    peer-threads))))
 
 ;; Str [Listof Peer] ->
 ;; Router main
 (define (run-router asn peers)
   (displayln asn)
   (map displayln peers)
-  (void))
+  (run-router/conns
+   (for/list ([peer (in-list peers)])
+      (define-values [sock-in sock-out]
+        (unix-socket-connect (ip->string (peer-ip peer))
+                             'SOCK_SEQPACKET))
+      (peer-conn peer
+                 sock-in
+                 sock-out))))
 
 (module+ main
-    (command-line
+  (command-line
-     #:program "router"
+   #:program "router"
-     #:args
+   #:args
-     (asn . peers)
+   (asn . peers)
-     ;; Run the router
+   ;; Run the router
-     (run-router asn (map string->peer peers))))
+   (run-router asn (map string->peer peers))))
+
+(module+ test
+
+  (define-values [in1 out1] (make-pipe))
+  (define-values [in2 out2] (make-pipe))
+  (define p1 (peer-conn (string->peer "1.2.3.4-cust") in1 out1))
+  (define p2 (peer-conn (string->peer "1.2.3.5-peer") in2 out2))
+
+  (define abort-router
+    (run-router/conns "123"
+                      (list p1 p2)))
+
+  (void
+   (write-string "{\"a\": 1, \"b\": [1,2,3]}" out1)))