improve readability of the examples

examples/dns_mass_resolve.py

@@ -8,12 +8,12 @@ results faster.
 """
 
 from gevent import socket
-from gevent import pool
+from gevent.pool import Pool
 
 N = 1000
 
 # limit ourselves to max 10 simultaneous outstanding requests
-p = pool.Pool(10)
+pool = Pool(10)
 
 finished = 0
 
@@ -29,7 +29,7 @@ def job(url):
         finished += 1
 
 for x in xrange(10, N):
-    p.spawn(job, '%s.com' % x)
+    pool.spawn(job, '%s.com' % x)
 
-p.join(timeout=2)
+pool.join(timeout=2)
 print 'finished within 2 seconds: %s/%s' % (finished, N)

examples/echoserver.py

@@ -32,14 +32,14 @@ and then 'quit')
 import gevent
 from gevent import socket
 
-def handle_socket(f):
+def handle_socket(fileobj):
     while True:
-        x = f.readline()
-        if not x:
+        line = fileobj.readline()
+        if not line:
             break
-        f.write(x)
-        f.flush()
-        print "echoed", repr(x)
+        fileobj.write(line)
+        fileobj.flush()
+        print "echoed", repr(line)
     print "client disconnected"
 
 if __name__ == '__main__':

examples/httpserver.py

@@ -6,14 +6,14 @@ WSGI interface is a safer choice, see examples/wsgiserver.py.
 """
 from gevent import http
 
-def callback(r):
-    print r
-    if r.uri == '/':
-        r.add_output_header('Content-Type', 'text/html')
-        r.send_reply(200, "OK", '<b>hello world</b>')
+def callback(request):
+    print request
+    if request.uri == '/':
+        request.add_output_header('Content-Type', 'text/html')
+        request.send_reply(200, "OK", '<b>hello world</b>')
     else:
-        r.add_output_header('Content-Type', 'text/html')
-        r.send_reply(404, "Not Found", "<h1>Not Found</h1>")
+        request.add_output_header('Content-Type', 'text/html')
+        request.send_reply(404, "Not Found", "<h1>Not Found</h1>")
 
 print 'Serving on 8088...'
 http.HTTPServer(callback).serve_forever(('0.0.0.0', 8088))

examples/webproxy.py

@@ -10,8 +10,11 @@ from cgi import escape
 from urllib import unquote
 
 
+PORT = 8088
+PROXY_URL = 'http://127.0.0.1:%s/' % PORT
+
+
 def application(env, start_response):
-    proxy_url = 'http://127.0.0.1:%(SERVER_PORT)s/' % env
     method = env['REQUEST_METHOD']
     path = env['PATH_INFO']
     if env['QUERY_STRING']:
@@ -21,33 +24,11 @@ def application(env, start_response):
         start_response('200 OK', [('Content-Type', 'text/html')])
         return [FORM]
     elif method == 'GET':
-        if '://' not in path:
-            path = 'http://' + path
-        try:
-            try:
-                r = urllib2.urlopen(path)
-            except urllib2.HTTPError, ex:
-                r = ex
-            print '%s: %s %s' % (path, r.code, r.msg)
-            headers = [(k, v) for (k, v) in r.headers.items() if k not in drop_headers]
-            parsed_path = urlparse(path)
-            host = (parsed_path.scheme or 'http') + '://' + parsed_path.netloc
-        except Exception, ex:
-            sys.stderr.write('error while reading %s:\n' % path)
-            traceback.print_exc()
-            tb = traceback.format_exc()
-            start_response('502 Bad Gateway', [('Content-Type', 'text/html')])
-            return ['<h1>%s</h1><h2>%s</h2><pre>%s</pre>' % (escape(str(ex) or ex.__class__.__name__ or 'Error'), escape(path), escape(tb))]
-        #for key, value in r.headers:
-        else:
-            start_response('%s %s' % (r.code, r.msg), headers)
-            data = r.read()
-            data = fix_links(data, proxy_url, host)
-            return [data]
+        return proxy(path, start_response)
     elif (method, path) == ('POST', ''):
         key, value = env['wsgi.input'].read().strip().split('=')
         assert key == 'url', repr(key)
-        start_response('302 Found', [('Location', join(proxy_url, unquote(value)))])
+        start_response('302 Found', [('Location', join(PROXY_URL, unquote(value)))])
     elif method == 'POST':
         start_response('404 Not Found', [])
     else:
@@ -55,6 +36,31 @@ def application(env, start_response):
     return []
 
 
+def proxy(path, start_response):
+    if '://' not in path:
+        path = 'http://' + path
+    try:
+        try:
+            response = urllib2.urlopen(path)
+        except urllib2.HTTPError, ex:
+            response = ex
+        print '%s: %s %s' % (path, response.code, response.msg)
+        headers = [(k, v) for (k, v) in response.headers.items() if k not in drop_headers]
+        parsed_path = urlparse(path)
+        host = (parsed_path.scheme or 'http') + '://' + parsed_path.netloc
+    except Exception, ex:
+        sys.stderr.write('error while reading %s:\n' % path)
+        traceback.print_exc()
+        tb = traceback.format_exc()
+        start_response('502 Bad Gateway', [('Content-Type', 'text/html')])
+        error_str = escape(str(ex) or ex.__class__.__name__ or 'Error')
+        return ['<h1>%s</h1><h2>%s</h2><pre>%s</pre>' % (error_str, escape(path), escape(tb))]
+    else:
+        start_response('%s %s' % (response.code, response.msg), headers)
+        data = response.read()
+        data = fix_links(data, PROXY_URL, host)
+        return [data]
+
 
 def join(url1, *rest):
     if not rest:
@@ -108,6 +114,6 @@ FORM = """<html><head>
 if __name__ == '__main__':
     #import doctest
     #doctest.testmod()
-    print 'Serving on 8088...'
-    wsgi.WSGIServer(('', 8088), application).serve_forever()
+    print 'Serving on %s...' % PORT
+    wsgi.WSGIServer(('', PORT), application).serve_forever()
 

examples/webpy.py

+#!/usr/bin/python
+
+"""A web.py application powered by gevent"""
+
+from gevent import monkey; monkey.patch_all()
+from gevent.wsgi import WSGIServer
+import gevent
+import web
+
+urls = ("/", "index",
+        '/long', 'long_polling')
+
+class index:
+    def GET(self):
+        return 'Hello, world!<br><a href="/long">/long</a>'
+
+class long_polling:
+    # Since gevent.wsgi executes each incoming connection in a separate greenlet
+    # long running requests such as this one don't block one another;
+    # and thanks to "monkey.patch_all()" statement at the top, thread-local storage used by web.ctx
+    # becomes greenlet-local storage thus making requests isolated as they should be.
+    def GET(self):
+        print 'handling GET context id = %s' % (id(web.ctx._getd()), )
+        gevent.sleep(10) # possible to block the request indefinitely, without harming others
+        return 'Hello, 10 seconds later'
+
+if __name__ == "__main__":
+    application = web.application(urls, globals()).wsgifunc()
+    print 'Serving on 8088...'
+    WSGIServer(('', 8088), application).serve_forever()
+