use element screenshot to capture about

Author: bollwyvl

atest/acceptance/10_lab/00_shell.robot

@@ -12,6 +12,7 @@ Get Help
     Open JupyterLab
     Click JupyterLab Menu    Help
     Click JupyterLab Menu Item    About JupyterLab
+    Capture Element Screenshot    css:.jp-Dialog-content    ${OUTPUT_DIR}${/}about.png
     Click Element    css:${JLAB CSS ACCEPT}
 
 *** Keywords ***

atest/run.py

@@ -2,6 +2,9 @@
 import subprocess
 import os
 
+# import for PATH side-effect. yuck.
+import chromedriver_binary  # noqa
+
 here = os.path.dirname(__file__)
 out = os.path.join(here, "..", "_artifacts", "test_output")
 tests = os.path.join(here, "acceptance")

src/JupyterLibrary/core.py

@@ -7,10 +7,11 @@
 from SeleniumLibrary import SeleniumLibrary
 from SeleniumLibrary.utils.librarylistener import LibraryListener
 
-from .keywords import server
+from .keywords import screenshots, server
 
 
 RESOURCES = join(dirname(__file__), "resources")
+CLIENTS = ["jupyterlab"]
 
 
 class JupyterLibrary(SeleniumLibrary):
@@ -40,7 +41,9 @@ def __init__(
             run_on_failure="Capture Page Screenshot",
             screenshot_root_directory=None,
         )
-        self.add_library_components([server.ServerKeywords(self)])
+        self.add_library_components(
+            [server.ServerKeywords(self), screenshots.ScreenshotKeywords(self)]
+        )
         self.ROBOT_LIBRARY_LISTENER = JupyterLibraryListener()
 
 
@@ -52,6 +55,8 @@ class JupyterLibraryListener(LibraryListener):
 
     def start_suite(self, name, attrs):
         super(JupyterLibraryListener, self).start_suite(name, attrs)
-        for path in glob(join(RESOURCES, "jupyterlab", "*.robot")):
-            resource = "JupyterLibrary/resources/jupyterlab/{}".format(basename(path))
-            BuiltIn().import_resource(resource)
+        for client in CLIENTS:
+            for path in glob(join(RESOURCES, client, "*.robot")):
+                BuiltIn().import_resource(
+                    "JupyterLibrary/resources/{}/{}".format(client, basename(path))
+                )

src/JupyterLibrary/keywords/screenshots.py

@@ -0,0 +1,51 @@
+from robot.libraries.BuiltIn import BuiltIn
+from SeleniumLibrary.base import LibraryComponent, keyword
+
+
+try:
+    import cv2
+except ImportError:
+    cv2 = None
+
+try:
+    from PIL import Image
+except ImportError:
+    Image = None
+
+
+class ScreenshotKeywords(LibraryComponent):
+    @keyword
+    def capture_element_screenshot(self, locator, filename, embed=True):
+        el = self.find_element(locator)
+        BuiltIn().run_keyword("Capture Page Screenshot", filename)
+        rect = {**el.location, **el.size}
+        self.crop_image(filename, **self.round_dict(rect))
+
+    def round_dict(self, dict):
+        return {
+            k: int(round(v)) if isinstance(v, float) else v for k, v in dict.items()
+        }
+
+    @keyword
+    def crop_image(self, in_file, x, y, width, height, out_file=None):
+        if cv2:
+            return self.crop_with_opencv(in_file, x, y, width, height, out_file)
+        elif Image:
+            return self.crop_with_pillow(in_file, x, y, width, height, out_file)
+
+    def crop_with_opencv(self, in_file, x, y, width, height, out_file=None):
+        out_file = out_file or in_file
+        im = cv2.imread(in_file)
+        im = im[int(y) : int(y + height), int(x) : int(x + width)]
+        cv2.imwrite(out_file, im)
+        return out_file
+
+    def crop_with_pillow(self, in_file, x, y, width, height, out_file=None):
+        out_file = out_file or in_file
+        img = Image.open(in_file)
+        area = img.crop((int(x), int(y), int(x + width), int(y + height)))
+
+        with open(out_file, "wb") as output:
+            area.save(output, "png")
+
+        return out_file

src/JupyterLibrary/keywords/server.py

@@ -7,10 +7,6 @@
 from tornado.escape import json_decode
 
 
-class NBServer(object):
-    process = None
-
-
 class ServerKeywords(LibraryComponent):
     _nbserver_handles = []