ChromeEngine

README.md

@@ -27,7 +27,55 @@
 - Operations on Tabs under stable websocket
   - Package very commonly used functions
 
+# What's More?
 
+As we known, `Chrome` browsers (including various webdriver versions) will have the following problems **in a long-running scene**:
+   1. memory leak
+   2. missing websocket connections
+   3. infinitely growing cache
+   4. other unpredictable problems...
+
+So you may need a more stable process pool scheduling scheme:
+
+```python
+import asyncio
+from ichrome.pool import ChromeEngine
+
+
+def test_pool():
+
+    async def _test_pool():
+
+        tab_callback1 = r'''async def tab_callback(self, tab, url, timeout):
+            await tab.set_url(url, timeout=5)
+            return 'Bing' in (await tab.title)'''
+
+        async def tab_callback2(self, tab, url, timeout):
+            await tab.set_url(url, timeout=5)
+            return 'Bing' in (await tab.title)
+
+        async with ChromeEngine(max_concurrent_tabs=5,
+                                headless=True,
+                                disable_image=True) as ce:
+            tasks = [
+                asyncio.ensure_future(
+                    ce.do('http://bing.com', tab_callback1, timeout=10))
+                for _ in range(3)
+            ] + [
+                asyncio.ensure_future(
+                    ce.do('http://bing.com', tab_callback2, timeout=10))
+                for _ in range(3)
+            ]
+            for task in tasks:
+                assert (await task) is True
+
+    # asyncio.run will raise aiohttp issue: https://github.com/aio-libs/aiohttp/issues/4324
+    asyncio.get_event_loop().run_until_complete(_test_pool())
+
+
+if __name__ == "__main__":
+    test_pool()
+```
 
 # Install
 
@@ -417,5 +465,6 @@ Test Code: [examples_sync.py](https://github.com/ClericPy/ichrome/blob/master/ex
 - [x] Add some useful examples.
 - [x] Coroutine support (for asyncio).
 - [x] Standard test cases.
+- [x] Stable Chrome Process Pool.
 - [ ] HTTP apis server console [fastapi]. (maybe a new lib)
 - [ ] ~~Complete document.~~

examples_async.py

@@ -1,7 +1,7 @@
 import asyncio
 from typing import List
 
-from ichrome import AsyncChromeDaemon
+from ichrome import AsyncChromeDaemon, ChromeEngine
 from ichrome.async_utils import Chrome, Tab, Tag, logger
 
 logger.setLevel('DEBUG')
@@ -327,5 +327,37 @@ def on_shutdown(chromed):
     assert AsyncChromeDaemon.bye
 
 
+def test_chrome_engine():
+
+    async def _test_chrome_engine():
+
+        tab_callback1 = r'''async def tab_callback(self, tab, url, timeout):
+            await tab.set_url(url, timeout=5)
+            return 'Bing' in (await tab.title)'''
+
+        async def tab_callback2(self, tab, url, timeout):
+            await tab.set_url(url, timeout=5)
+            return 'Bing' in (await tab.title)
+
+        async with ChromeEngine(max_concurrent_tabs=5,
+                                headless=True,
+                                disable_image=True) as ce:
+            tasks = [
+                asyncio.ensure_future(
+                    ce.do('http://bing.com', tab_callback1, timeout=10))
+                for _ in range(3)
+            ] + [
+                asyncio.ensure_future(
+                    ce.do('http://bing.com', tab_callback2, timeout=10))
+                for _ in range(3)
+            ]
+            for task in tasks:
+                assert (await task) is True
+            print('test_chrome_engine ok')
+    # asyncio.run will raise aiohttp issue: https://github.com/aio-libs/aiohttp/issues/4324
+    asyncio.get_event_loop().run_until_complete(_test_chrome_engine())
+
+
 if __name__ == "__main__":
-    asyncio.run(test_examples())
+    test_chrome_engine()
+    asyncio.get_event_loop().run_until_complete(test_examples())

ichrome/__init__.py

@@ -4,11 +4,12 @@
 from .daemon import AsyncChromeDaemon, ChromeDaemon, ChromeWorkers
 from .debugger import get_a_tab
 from .logs import logger
+from .pool import ChromeEngine
 from .sync_utils import Chrome, Tab
 
-__version__ = "2.3.9"
+__version__ = "2.4.0"
 __tips__ = "[github]: https://github.com/ClericPy/ichrome\n[cdp]: https://chromedevtools.github.io/devtools-protocol/\n[cmd args]: https://peter.sh/experiments/chromium-command-line-switches/"
 __all__ = [
     'Chrome', 'ChromeDaemon', 'Tab', 'Tag', 'AsyncChrome', 'AsyncTab', 'logger',
-    'AsyncChromeDaemon', 'ChromeWorkers', 'get_a_tab'
+    'AsyncChromeDaemon', 'ChromeWorkers', 'get_a_tab', 'ChromeEngine'
 ]

ichrome/async_utils.py

@@ -1550,14 +1550,17 @@ async def get_bounding_client_rect(self,
                                            timeout=timeout)
 
     async def screenshot_element(self,
-                                 cssselector: str,
+                                 cssselector: str = None,
                                  scale=1,
                                  format: str = 'png',
                                  quality: int = 100,
                                  fromSurface: bool = True,
                                  save_path=None,
                                  timeout=NotSet):
-        clip = await self.get_element_clip(cssselector, scale=scale)
+        if cssselector:
+            clip = await self.get_element_clip(cssselector, scale=scale)
+        else:
+            clip = None
         return await self.screenshot(format=format,
                                      quality=quality,
                                      clip=clip,