add download_file, bool volatile state

test/test_download_file.py

@@ -0,0 +1,29 @@
+from unittest import TestCase
+import os
+
+from hexlib.web import download_file
+
+
+class TestDownloadFile(TestCase):
+
+    def test_download_file(self):
+        download_file("http://ovh.net/files/10Mb.dat", "/tmp/10Mb.dat")
+        self.assertTrue(os.path.exists("/tmp/10Mb.dat"))
+        os.remove("/tmp/10Mb.dat")
+
+    def test_download_file_error(self):
+        exceptions = []
+
+        def cb(ex):
+            exceptions.append(ex)
+
+        download_file("http://thisUrlIsInvalid", "/tmp/file.txt", err_cb=cb, retries=3)
+        self.assertFalse(os.path.exists("/tmp/10Mb.dat"))
+        self.assertEqual(len(exceptions), 3)
+
+    def test_download_file_meta(self):
+        download_file("http://ovh.net/files/10Mb.dat", "/tmp/10Mb.dat", save_meta=True)
+        self.assertTrue(os.path.exists("/tmp/10Mb.dat"))
+        self.assertTrue(os.path.exists("/tmp/10Mb.dat.meta"))
+        os.remove("/tmp/10Mb.dat")
+        # os.remove("/tmp/10Mb.dat.meta")