Merge pull request #1190 from dcslin/dev-postgresql

Add implementations for data downloading in cnn ms example

examples/cnn_ms/data/download_cifar10.py

@@ -0,0 +1,49 @@
+#!/usr/bin/env python
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+# 
+#     http://www.apache.org/licenses/LICENSE-2.0
+# 
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# 
+
+from __future__ import print_function
+from future import standard_library
+standard_library.install_aliases()
+import urllib.request, urllib.parse, urllib.error
+import tarfile
+import os
+import sys
+
+
+def extract_tarfile(filepath):
+    if os.path.exists(filepath):
+        print('The tar file does exist. Extracting it now..')
+        with tarfile.open(filepath, 'r') as f:
+            f.extractall('/tmp/')  # need to specify a local directory
+        print('Finished!')
+        sys.exit(0)
+
+
+def do_download(dirpath, gzfile, url):
+    print('Downloading CIFAR from %s' % (url))
+    urllib.request.urlretrieve(url, gzfile)
+    extract_tarfile(gzfile)
+    print('Finished!')
+
+
+if __name__ == '__main__':
+    dirpath = '/tmp/'  # need to specify a local directory
+    gzfile = dirpath + 'cifar-10-python.tar.gz'
+    url = 'http://www.cs.toronto.edu/~kriz/cifar-10-python.tar.gz'
+    do_download(dirpath, gzfile, url)