add gif bot to support dynamic created gif file

examples/advanced/gif-bot.py

@@ -0,0 +1,89 @@
+"""doc"""
+# pylint: disable=R0801
+import asyncio
+import logging
+from typing import Optional, Union
+
+from wechaty_puppet import FileBox, ScanStatus  # type: ignore
+
+from wechaty import Wechaty, Contact
+from wechaty.user import Message, Room
+
+logging.basicConfig(level=logging.INFO)
+log = logging.getLogger(__name__)
+
+
+def create_gif():
+    """
+    refer to : https://note.nkmk.me/en/python-pillow-gif/
+
+    you can create gif file with your own code.
+    """
+    from PIL import Image, ImageDraw
+
+    images = []
+
+    width = 200
+    center = width // 2
+    color_1 = (0, 0, 0)
+    color_2 = (255, 255, 255)
+    max_radius = int(center * 1.5)
+    step = 8
+
+    for i in range(0, max_radius, step):
+        im = Image.new('RGB', (width, width), color_1)
+        draw = ImageDraw.Draw(im)
+        draw.ellipse((center - i, center - i, center + i, center + i), fill=color_2)
+        images.append(im)
+
+    for i in range(0, max_radius, step):
+        im = Image.new('RGB', (width, width), color_2)
+        draw = ImageDraw.Draw(im)
+        draw.ellipse((center - i, center - i, center + i, center + i), fill=color_1)
+        images.append(im)
+
+    images[0].save('./bot.gif',
+                   save_all=True, append_images=images[1:], optimize=False, duration=40, loop=0)
+
+
+class MyBot(Wechaty):
+    """
+    listen wechaty event with inherited functions, which is more friendly for
+    oop developer
+    """
+    def __init__(self):
+        super().__init__()
+
+    async def on_message(self, msg: Message):
+        """
+        listen for message event
+        """
+        from_contact = msg.talker()
+        text = msg.text()
+        room = msg.room()
+        if text == 'gif':
+            conversation: Union[
+                Room, Contact] = from_contact if room is None else room
+            await conversation.ready()
+            await conversation.say('dong')
+            file_box = FileBox.from_file('./bot.gif')
+            await conversation.say(file_box)
+
+    async def on_login(self, contact: Contact):
+        print(f'user: {contact} has login')
+
+    async def on_scan(self, status: ScanStatus, qr_code: Optional[str] = None,
+                      data: Optional[str] = None):
+        contact = self.Contact.load(self.contact_id)
+        print(f'user <{contact}> scan status: {status.name} , '
+              f'qr_code: {qr_code}')
+
+
+async def main():
+    """doc"""
+    create_gif()
+    bot = MyBot()
+    await bot.start()
+
+
+asyncio.run(main())