add HTTPretty==0.8.14 to requirement-dev; add check_connect and its testcase to request

pydu/request.py

@@ -1,6 +1,9 @@
 import os
 import shutil
 import tempfile
+import socket
+
+from pydu import logger
 from pydu.compat import PY2, string_types, urlparse, ulib
 from pydu.string import safeunicode
 
@@ -97,3 +100,24 @@ def download(url, dst=None):
     shutil.move(tmpfile, filename)
 
     return filename
+
+
+def check_connect(ip, port, retry=1, timeout=0.5):
+    while retry:
+        try:
+            s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        except socket.error as e:
+            logger.exception(e)
+            retry -= 1
+            continue
+
+        try:
+            s.settimeout(timeout)
+            s.connect((ip, port))
+            return s.getsockname()[0]
+        except socket.error:
+            logger.error("Connect to ip:%s port:%d fail", ip, port)
+            s.close()
+        finally:
+            retry -= 1
+    return None

requirements-dev.txt

@@ -1,2 +1,3 @@
 pytest
-coveralls
+coveralls
+HTTPretty==0.8.14

tests/test_request.py

@@ -1,4 +1,5 @@
-from pydu.request import FileName
+import httpretty
+from pydu.request import FileName, check_connect
 
 
 def test_filename_from_url():
@@ -36,3 +37,10 @@ def test_filename_from_headers():
 
     headers = 'Content-Disposition: attachment; filename='
     assert FileName.from_headers(headers) is None
+
+
+@httpretty.activate
+def test_check_connect():
+    httpretty.register_uri(httpretty.GET, 'http://localhost')
+    assert check_connect('http://localhost', port=80, timeout=0.01)
+    assert not check_connect('http://localhost', port=8000, timeout=0.01)