Changed all the import statements in all modules in the examples

directory to import only what is needed.

This fix issue #464

Author: denisra

examples/cacheclt.py

@@ -5,10 +5,11 @@
 
 import argparse
 import asyncio
-from asyncio import test_utils
+import asyncio.test_utils
 import json
 import logging
 
+
 ARGS = argparse.ArgumentParser(description='Cache client example.')
 ARGS.add_argument(
     '--tls', action='store_true', dest='tls',
@@ -106,7 +107,7 @@ def activity(self):
                 self.reader, self.writer = yield from asyncio.open_connection(
                     self.host, self.port, ssl=self.sslctx, loop=self.loop)
             except Exception as exc:
-                backoff = min(args.max_backoff, backoff + (backoff//2) + 1)
+                backoff = min(args.max_backoff, backoff + (backoff // 2) + 1)
                 logging.info('Error connecting: %r; sleep %s', exc, backoff)
                 yield from asyncio.sleep(backoff, loop=self.loop)
                 continue
@@ -191,7 +192,7 @@ def w(g):
 
     key = 'foo-%s' % label
     while True:
-        logging.info('%s %s', label, '-'*20)
+        logging.info('%s %s', label, '-' * 20)
         try:
             ret = yield from w(cache.set(key, 'hello-%s-world' % label))
             logging.info('%s set %s', label, ret)

examples/child_process.py

@@ -26,6 +26,7 @@
 # Return a write-only transport wrapping a writable pipe
 #
 
+
 @asyncio.coroutine
 def connect_write_pipe(file):
     loop = asyncio.get_event_loop()
@@ -36,10 +37,12 @@ def connect_write_pipe(file):
 # Wrap a readable pipe in a stream
 #
 
+
 @asyncio.coroutine
 def connect_read_pipe(file):
     loop = asyncio.get_event_loop()
     stream_reader = asyncio.StreamReader(loop=loop)
+
     def factory():
         return asyncio.StreamReaderProtocol(stream_reader)
     transport, _ = yield from loop.connect_read_pipe(factory, file)
@@ -85,7 +88,7 @@ def writeall(fd, buf):
     stderr, stderr_transport = yield from connect_read_pipe(p.stderr)
 
     # interact with subprocess
-    name = {stdout:'OUT', stderr:'ERR'}
+    name = {stdout: 'OUT', stderr: 'ERR'}
     registered = {asyncio.Task(stderr.readline()): stderr,
                   asyncio.Task(stdout.readline()): stdout}
     while registered:
@@ -116,6 +119,7 @@ def writeall(fd, buf):
     stdout_transport.close()
     stderr_transport.close()
 
+
 if __name__ == '__main__':
     if sys.platform == 'win32':
         loop = ProactorEventLoop()

examples/crawl.py

@@ -341,7 +341,7 @@ def send_request(self):
         self.headers.append(('User-Agent', 'asyncio-example-crawl/0.0'))
         self.headers.append(('Host', self.netloc))
         self.headers.append(('Accept', '*/*'))
-        ##self.headers.append(('Accept-Encoding', 'gzip'))
+        # self.headers.append(('Accept-Encoding', 'gzip'))
         for key, value in self.headers:
             line = '%s: %s' % (key, value)
             yield from self.putline(line)
@@ -519,7 +519,7 @@ def fetch(self):
                 self.exceptions.append(exc)
                 self.log(1, 'try', self.tries, 'for', self.url,
                             'raised', repr(exc))
-                ##import pdb; pdb.set_trace()
+                # import pdb; pdb.set_trace()
                 # Don't reuse the connection in this case.
             finally:
                 if self.request is not None:
@@ -534,7 +534,7 @@ def fetch(self):
             self.next_url = urllib.parse.urljoin(self.url, next_url)
             if self.max_redirect > 0:
                 self.log(1, 'redirect to', self.next_url, 'from', self.url)
-                self.crawler.add_url(self.next_url, self.max_redirect-1)
+                self.crawler.add_url(self.next_url, self.max_redirect - 1)
             else:
                 self.log(0, 'redirect limit reached for', self.next_url,
                             'from', self.url)

examples/echo_client_tulip.py

@@ -1,7 +1,9 @@
 import asyncio
 
+
 END = b'Bye-bye!\n'
 
+
 @asyncio.coroutine
 def echo_client():
     reader, writer = yield from asyncio.open_connection('localhost', 8000)
@@ -15,6 +17,7 @@ def echo_client():
             break
     writer.close()
 
+
 loop = asyncio.get_event_loop()
 loop.run_until_complete(echo_client())
 loop.close()

examples/echo_server_tulip.py

@@ -1,9 +1,11 @@
 import asyncio
 
+
 @asyncio.coroutine
 def echo_server():
     yield from asyncio.start_server(handle_connection, 'localhost', 8000)
 
+
 @asyncio.coroutine
 def handle_connection(reader, writer):
     while True:
@@ -12,6 +14,7 @@ def handle_connection(reader, writer):
             break
         writer.write(data)
 
+
 loop = asyncio.get_event_loop()
 loop.run_until_complete(echo_server())
 try:

examples/fetch0.py

@@ -1,13 +1,12 @@
 """Simplest possible HTTP client."""
 
+import asyncio
 import sys
 
-from asyncio import *
 
-
-@coroutine
+@asyncio.coroutine
 def fetch():
-    r, w = yield from open_connection('python.org', 80)
+    r, w = yield from asyncio.open_connection('python.org', 80)
     request = 'GET / HTTP/1.0\r\n\r\n'
     print('>', request, file=sys.stderr)
     w.write(request.encode('latin-1'))
@@ -23,7 +22,7 @@ def fetch():
 
 
 def main():
-    loop = get_event_loop()
+    loop = asyncio.get_event_loop()
     try:
         body = loop.run_until_complete(fetch())
     finally:

examples/fetch1.py

@@ -3,11 +3,10 @@
 This version adds URL parsing (including SSL) and a Response object.
 """
 
+import asyncio
 import sys
 import urllib.parse
 
-from asyncio import *
-
 
 class Response:
 
@@ -18,27 +17,30 @@ def __init__(self, verbose=True):
         self.reason = None  # 'Ok'
         self.headers = []  # [('Content-Type', 'text/html')]
 
-    @coroutine
+    @asyncio.coroutine
     def read(self, reader):
-        @coroutine
+        @asyncio.coroutine
         def getline():
             return (yield from reader.readline()).decode('latin-1').rstrip()
         status_line = yield from getline()
-        if self.verbose: print('<', status_line, file=sys.stderr)
+        if self.verbose:
+            print('<', status_line, file=sys.stderr)
         self.http_version, status, self.reason = status_line.split(None, 2)
         self.status = int(status)
         while True:
             header_line = yield from getline()
             if not header_line:
                 break
-            if self.verbose: print('<', header_line, file=sys.stderr)
+            if self.verbose:
+                print('<', header_line, file=sys.stderr)
             # TODO: Continuation lines.
             key, value = header_line.split(':', 1)
             self.headers.append((key, value.strip()))
-        if self.verbose: print(file=sys.stderr)
+        if self.verbose:
+            print(file=sys.stderr)
 
 
-@coroutine
+@asyncio.coroutine
 def fetch(url, verbose=True):
     parts = urllib.parse.urlparse(url)
     if parts.scheme == 'http':
@@ -57,7 +59,7 @@ def fetch(url, verbose=True):
     request = 'GET %s HTTP/1.0\r\n\r\n' % path
     if verbose:
         print('>', request, file=sys.stderr, end='')
-    r, w = yield from open_connection(parts.hostname, port, ssl=ssl)
+    r, w = yield from asyncio.open_connection(parts.hostname, port, ssl=ssl)
     w.write(request.encode('latin-1'))
     response = Response(verbose)
     yield from response.read(r)
@@ -66,7 +68,7 @@ def fetch(url, verbose=True):
 
 
 def main():
-    loop = get_event_loop()
+    loop = asyncio.get_event_loop()
     try:
         body = loop.run_until_complete(fetch(sys.argv[1], '-v' in sys.argv))
     finally:

examples/fetch2.py

@@ -3,11 +3,10 @@
 This version adds a Request object.
 """
 
+import asyncio
+from http.client import BadStatusLine
 import sys
 import urllib.parse
-from http.client import BadStatusLine
-
-from asyncio import *
 
 
 class Request:
@@ -34,13 +33,13 @@ def __init__(self, url, verbose=True):
         self.reader = None
         self.writer = None
 
-    @coroutine
+    @asyncio.coroutine
     def connect(self):
         if self.verbose:
             print('* Connecting to %s:%s using %s' %
                   (self.hostname, self.port, 'ssl' if self.ssl else 'tcp'),
                   file=sys.stderr)
-        self.reader, self.writer = yield from open_connection(self.hostname,
+        self.reader, self.writer = yield from asyncio.open_connection(self.hostname,
                                                               self.port,
                                                               ssl=self.ssl)
         if self.verbose:
@@ -51,20 +50,22 @@ def connect(self):
     def putline(self, line):
         self.writer.write(line.encode('latin-1') + b'\r\n')
 
-    @coroutine
+    @asyncio.coroutine
     def send_request(self):
         request = '%s %s %s' % (self.method, self.full_path, self.http_version)
-        if self.verbose: print('>', request, file=sys.stderr)
+        if self.verbose:
+            print('>', request, file=sys.stderr)
         self.putline(request)
         if 'host' not in {key.lower() for key, _ in self.headers}:
             self.headers.insert(0, ('Host', self.netloc))
         for key, value in self.headers:
             line = '%s: %s' % (key, value)
-            if self.verbose: print('>', line, file=sys.stderr)
+            if self.verbose:
+                print('>', line, file=sys.stderr)
             self.putline(line)
         self.putline('')
 
-    @coroutine
+    @asyncio.coroutine
     def get_response(self):
         response = Response(self.reader, self.verbose)
         yield from response.read_headers()
@@ -81,14 +82,15 @@ def __init__(self, reader, verbose=True):
         self.reason = None  # 'Ok'
         self.headers = []  # [('Content-Type', 'text/html')]
 
-    @coroutine
+    @asyncio.coroutine
     def getline(self):
         return (yield from self.reader.readline()).decode('latin-1').rstrip()
 
-    @coroutine
+    @asyncio.coroutine
     def read_headers(self):
         status_line = yield from self.getline()
-        if self.verbose: print('<', status_line, file=sys.stderr)
+        if self.verbose:
+            print('<', status_line, file=sys.stderr)
         status_parts = status_line.split(None, 2)
         if len(status_parts) != 3:
             raise BadStatusLine(status_line)
@@ -98,13 +100,15 @@ def read_headers(self):
             header_line = yield from self.getline()
             if not header_line:
                 break
-            if self.verbose: print('<', header_line, file=sys.stderr)
+            if self.verbose:
+                print('<', header_line, file=sys.stderr)
             # TODO: Continuation lines.
             key, value = header_line.split(':', 1)
             self.headers.append((key, value.strip()))
-        if self.verbose: print(file=sys.stderr)
+        if self.verbose:
+            print(file=sys.stderr)
 
-    @coroutine
+    @asyncio.coroutine
     def read(self):
         nbytes = None
         for key, value in self.headers:
@@ -118,7 +122,7 @@ def read(self):
         return body
 
 
-@coroutine
+@asyncio.coroutine
 def fetch(url, verbose=True):
     request = Request(url, verbose)
     yield from request.connect()
@@ -129,7 +133,7 @@ def fetch(url, verbose=True):
 
 
 def main():
-    loop = get_event_loop()
+    loop = asyncio.get_event_loop()
     try:
         body = loop.run_until_complete(fetch(sys.argv[1], '-v' in sys.argv))
     finally: