Comments

Author: tony-martin-aste

src/Crusse/JobServer/EventLoop.php

@@ -1,5 +1,18 @@
 <?php
 
+//
+// TODO
+//
+// http://docs.libuv.org/en/v1.x/design.html
+//
+// "The event loop follows the rather usual single threaded asynchronous I/O approach: all (network) I/O is performed on non-blocking sockets. As part of a loop iteration **the loop will block waiting for I/O activity on sockets which have been added to the poller** and callbacks will be fired indicating socket conditions (readable, writable hangup) so handles can read, write or perform the desired I/O operation."
+//
+// - create a watchSocket() method for adding server and client sockets
+// - emit events (run eventCallback with a 'writable' event) when a socket has sent a _full_ Request, and becomes writable
+//   - pass the callback the Request, and maybe a SocketWriter (or make the callback return a Response|null)
+// - implement BlockingEventLoop and NonBlockingEventLoop (with stream_select()) to test performance diff (if any)
+//
+
 namespace Crusse\JobServer;
 
 class EventLoop {

src/Crusse/JobServer/Server.php

@@ -74,6 +74,90 @@
 worker3:    r++r++r++w++w++w      rrrww+w
 server:                     ++++++
 
+-----------------------------------------------------------
+
+
+Blocking i/o:
+-------------
+
+Server:
+
+  results = []
+  stream_socket_server
+  while ( unfinished jobs )
+    stream_socket_accept
+    while ( got data )
+      stream_socket_recvfrom
+    results[] = data
+    stream_socket_sendto
+    fclose
+
+Worker:
+
+  stream_socket_client
+  stream_socket_sendto [register worker with server]
+  stream_socket_recvfrom [get first job from server]
+  while ( got job )
+    stream_socket_sendto [send result]
+    stream_socket_recvfrom [get another job]
+
+
+Non-blocking i/o:
+-----------------
+
+Server:
+
+  clients = []
+  writeBufferPerClient = []
+  readBufferPerClient = []
+  stream_socket_server
+  stream_set_blocking( server socket not blocking )
+  while ( unfinished jobs )
+    stream_select( readable: clients + server, writable: clients )
+    if ( server is readable )
+      clients[] = stream_socket_accept
+      stream_set_blocking( client socket not blocking )
+    foreach ( clients[] )
+      if ( is readable )
+        while ( got data, which means client socket is open )
+          stream_socket_recvfrom
+          readBufferPerClient[] .= data
+        if ( no received data )
+          results[] = Request(readBuffer)->getBody/Headers()
+      if ( is writable )
+        while ( didn't write all bytes of writeBufferPerClient[current] yet )
+          stream_socket_sendto
+        if ( writeBufferPerClient[current] is empty )
+          fclose
+          unset( clients[current] )
+
+Worker:
+
+  initialized = false
+  jobQueue = []
+  resultsQueue = []
+  readBuffer = ''
+  writeBuffer = ''
+  stream_socket_client
+  stream_set_blocking( client socket not blocking )
+  while ( true )
+    stream_select( readable: server, writable: server )
+    if ( server is writable )
+      if ( !initialized )
+        writeBuffer = I'm a new worker, register me
+      else
+        writeBuffer = here's a job result resultsQueue.pop(), gimme another job
+      while ( didn't write all bytes of writeBuffer yet )
+        stream_socket_sendto
+      if ( writeBuffer is empty )
+        fclose
+    if ( server is readable )
+      while ( got data, which means client socket is open )
+        stream_socket_recvfrom
+        readBuffer .= data
+      if ( no received data )
+        jobQueue[] = Request(readBuffer)->getBody/Headers()
+
 
 */