update from Atlas with major reorg

attic/concurrency/charfinder/tcp_charfinder.py

@@ -0,0 +1,61 @@
+#!/usr/bin/env python3
+
+import sys
+import asyncio
+
+from charfinder import UnicodeNameIndex
+
+CRLF = b'\r\n'
+PROMPT = b'?> '
+
+index = None  # a UnicodeNameIndex instance
+
+
+@asyncio.coroutine
+def handle_queries(reader, writer):
+    while True:
+        writer.write(PROMPT)  # can't yield from!
+        yield from writer.drain()  # must yield from!
+        data = yield from reader.readline()
+        try:
+            query = data.decode().strip()
+        except UnicodeDecodeError:
+            query = '\x00'
+        client = writer.get_extra_info('peername')
+        print('Received from {}: {!r}'.format(client, query))
+        if query:
+            if ord(query[:1]) < 32:
+                break
+            lines = list(index.find_description_strs(query))
+            if lines:
+                writer.writelines(line.encode() + CRLF for line in lines)
+            writer.write(index.status(query, len(lines)).encode() + CRLF)
+
+            yield from writer.drain()
+            print('Sent {} results'.format(len(lines)))
+
+    print('Close the client socket')
+    writer.close()
+
+
+def main(address='127.0.0.1', port=8888):
+    port = int(port)
+    loop = asyncio.get_event_loop()
+    coro = asyncio.start_server(handle_queries, address, port, loop=loop)
+    server = loop.run_until_complete(coro)
+
+    host = server.sockets[0].getsockname()
+    print('Serving on {}. Hit CTRL-C to stop.'.format(host))
+    try:
+        loop.run_forever()
+    except KeyboardInterrupt:  # CTRL+C pressed
+        pass
+
+    server.close()
+    loop.run_until_complete(server.wait_closed())
+    loop.close()
+
+
+if __name__ == '__main__':
+    index = UnicodeNameIndex()
+    main(*sys.argv[1:])