add stevedore extension

pythonmao · pythonmao · commit 3da30e73349f · 2016-12-24T19:30:05.000+08:00
diff --git a/test_stevedore/example1/example1/extension_driver.py b/test_stevedore/example1/example1/extension_driver.py
@@ -0,0 +1,40 @@
+# stevedore/example/load_as_extension.py
+from __future__ import print_function
+
+import argparse
+
+from stevedore import extension
+
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser()
+    parser.add_argument(
+        '--width',
+        default=60,
+        type=int,
+        help='maximum output width for text',
+    )
+    parsed_args = parser.parse_args()
+
+    data = {
+        'a': 'A',
+        'b': 'B',
+        'long': 'word ' * 80,
+    }
+
+    mgr = extension.ExtensionManager(
+        namespace='test_stevedore.study',
+        invoke_on_load=True,
+        invoke_args=(parsed_args.width,),
+    )
+
+    def format_data(ext, data):
+        return (ext.name, ext.obj.format(data))
+
+    results = mgr.map(format_data, data)
+
+    for name, result in results:
+        print('Formatter: {0}'.format(name))
+        for chunk in result:
+            print(chunk, end='')
+        print('')
