Merge 39a42e4 into b7a0019

CHANGES.md

@@ -38,3 +38,10 @@ A test and verification tool using Docker is now available
 Add two commands:
 * `browser-manager`
 * `screamshot`
+
+0.1.4
+===
+
+Add two functions:
+* `serialize`
+* `deserialize`

screamshot/__init__.py

@@ -5,10 +5,11 @@
 
 
 __author__ = """Maxime Courtet & Félix Cloup"""
-__version__ = "0.1.3"
+__version__ = "0.1.4"
 
 
 from screamshot.generate_bytes_img_functions import generate_bytes_img, generate_bytes_img_prom
+from screamshot.serializer import serialize, deserialize
 
 
-__all__ = ['generate_bytes_img', 'generate_bytes_img_prom']
+__all__ = ['generate_bytes_img', 'generate_bytes_img_prom', 'serialize', 'deserialize']

screamshot/serializer.py

@@ -0,0 +1,51 @@
+"""
+serialize and deserialize functions
+"""
+from base64 import b64encode, b64decode
+from json import dumps, loads
+from typing import Tuple, Dict, Union
+
+
+def serialize(img: bytes, metadata: dict = None) -> str:
+    """
+    This function serialize a binary bytes object
+
+    :param img: mandatory, the binary bytes object
+    :type img: bytes
+
+    :param metadata: optional, some metadata about the object
+    :type metadata: dict
+
+    :return: a json formatted string containing the image and metadata
+    :retype: str
+
+    .. info :: In the json formatted string, the image is saved in base64 format
+    """
+    b64_img = b64encode(img)
+    str_img = b64_img.decode('utf-8')
+    data = {'image': str_img} #type: Dict[str, Union[str, Dict[str, str]]]
+    if metadata:
+        data.update({'metadata': metadata})
+    json_img = dumps(data)
+    return json_img
+
+
+def deserialize(data: str) -> Tuple[bytes, dict]:
+    """
+    This function deserialize json formatted string
+
+    :param data: the string json formatted string to deserialize
+    :type data: str
+
+    :return: the binary bytes image and metadata
+    :retype: bytes, dict
+
+    .. warning :: The data should look like the following example: \
+        ``{"image": ..., "metadata": {...}}``
+    """
+    json_img = loads(data)
+    str_img = json_img.get('image')
+    metadata = json_img.get('metadata', {})
+    b64_img = str_img.encode('utf-8')
+    b_img = b64decode(b64_img)
+    return b_img, metadata

tests/test_serializer_unit.py

@@ -0,0 +1,72 @@
+from unittest import TestCase, main
+from json import loads
+from base64 import b64decode
+
+from screamshot.serializer import serialize, deserialize
+
+
+class TestSerializerUnit(TestCase):
+    def test_serialize_without_metadata(self):
+        data = b'Hello world'
+        json_data = serialize(data)
+
+        self.assertIsInstance(json_data, str)
+
+        extracted_data = loads(json_data)
+
+        self.assertTrue('image' in extracted_data)
+        self.assertFalse('metadata' in extracted_data)
+
+        b64_image = extracted_data.get('image').encode('utf-8')
+        self.assertNotEqual(data, b64_image)
+
+        b_image = b64decode(b64_image)
+        self.assertEqual(data, b_image)
+
+    def test_serialize_with_metadata(self):
+        data = b'Hello world'
+        name = 'hello_world.png'
+        author = 'John Doe'
+        json_data = serialize(data, metadata={'name': name, 'author': author})
+
+        extracted_data = loads(json_data)
+
+        self.assertTrue('image' in extracted_data)
+        self.assertTrue('metadata' in extracted_data)
+
+        metadata = extracted_data.get('metadata')
+        self.assertTrue('name' in metadata)
+        self.assertTrue('author' in metadata)
+        self.assertEqual(name, metadata.get('name'))
+        self.assertEqual(author, metadata.get('author'))
+
+        b64_image = extracted_data.get('image').encode('utf-8')
+        self.assertNotEqual(data, b64_image)
+
+        b_image = b64decode(b64_image)
+        self.assertEqual(data, b_image)
+
+    def test_deserialize_without_metadata(self):
+        data = '{"image": "SGVsbG8gd29ybGQ="}'
+        b_img, metadata = deserialize(data)
+
+        self.assertIsInstance(b_img, bytes)
+        self.assertIsInstance(metadata, dict)
+
+        self.assertEqual(b_img, b'Hello world')
+        self.assertEqual(metadata, {})
+
+    def test_deserialize_with_metadata(self):
+        data = '{"image": "SGVsbG8gd29ybGQ=", "metadata": {"name": "hello_world.png", \
+            "author": "John Doe"}}'
+        b_img, metadata = deserialize(data)
+
+        self.assertIsInstance(b_img, bytes)
+        self.assertIsInstance(metadata, dict)
+
+        self.assertEqual(b_img, b'Hello world')
+        self.assertEqual(metadata, {'name': 'hello_world.png', 'author': 'John Doe'})
+
+
+if __name__ == '__main__':
+    main()