feat: add a config to enable retina quality images in screenshots

superset/config.py

@@ -848,6 +848,8 @@ class CeleryConfig:  # pylint: disable=too-few-public-methods
 CSV_TO_HIVE_UPLOAD_DIRECTORY = "EXTERNAL_HIVE_TABLES/"
 # Function that creates upload directory dynamically based on the
 # database used, user and schema provided.
+
+
 def CSV_TO_HIVE_UPLOAD_DIRECTORY_FUNC(  # pylint: disable=invalid-name
     database: "Database",
     user: "models.User",  # pylint: disable=unused-argument
@@ -951,7 +953,9 @@ def CSV_TO_HIVE_UPLOAD_DIRECTORY_FUNC(  # pylint: disable=invalid-name
 # Provide a callable that receives a tracking_url and returns another
 # URL. This is used to translate internal Hadoop job tracker URL
 # into a proxied one
-TRACKING_URL_TRANSFORMER = lambda x: x
+def TRACKING_URL_TRANSFORMER(x):  # pylint: disable=invalid-name
+    return x
+
 
 # Interval between consecutive polls when using Hive Engine
 HIVE_POLL_INTERVAL = int(timedelta(seconds=5).total_seconds())
@@ -1085,7 +1089,11 @@ def SQL_QUERY_MUTATOR(  # pylint: disable=invalid-name,unused-argument
 WEBDRIVER_TYPE = "firefox"
 
 # Window size - this will impact the rendering of the data
-WEBDRIVER_WINDOW = {"dashboard": (1600, 2000), "slice": (3000, 1200)}
+WEBDRIVER_WINDOW = {
+    "dashboard": (1600, 2000),
+    "slice": (3000, 1200),
+    "pixel_density": 1,
+}
 
 # An optional override to the default auth hook used to provide auth to the
 # offline webdriver
@@ -1215,7 +1223,9 @@ def SQL_QUERY_MUTATOR(  # pylint: disable=invalid-name,unused-argument
 # to allow mutating the object with this callback.
 # This can be used to set any properties of the object based on naming
 # conventions and such. You can find examples in the tests.
-SQLA_TABLE_MUTATOR = lambda table: table
+def SQLA_TABLE_MUTATOR(table):  # pylint: disable=invalid-name
+    return table
+
 
 # Global async query config options.
 # Requires GLOBAL_ASYNC_QUERIES feature flag to be enabled.
@@ -1302,7 +1312,9 @@ def SQL_QUERY_MUTATOR(  # pylint: disable=invalid-name,unused-argument
 elif importlib.util.find_spec("superset_config") and not is_test():
     try:
         import superset_config  # pylint: disable=import-error
-        from superset_config import *  # type: ignore # pylint: disable=import-error,wildcard-import,unused-wildcard-import
+
+        # type: ignore # pylint: disable=import-error,wildcard-import,unused-wildcard-import
+        from superset_config import *
 
         print(f"Loaded your LOCAL configuration at [{superset_config.__file__}]")
     except Exception:

superset/utils/webdriver.py

@@ -27,7 +27,7 @@
     TimeoutException,
     WebDriverException,
 )
-from selenium.webdriver import chrome, firefox
+from selenium.webdriver import chrome, firefox, FirefoxProfile
 from selenium.webdriver.common.by import By
 from selenium.webdriver.remote.webdriver import WebDriver
 from selenium.webdriver.support import expected_conditions as EC
@@ -52,30 +52,45 @@ class DashboardStandaloneMode(Enum):
 
 class WebDriverProxy:
     def __init__(
-        self, driver_type: str, window: Optional[WindowSize] = None,
+        self,
+        driver_type: str,
+        window: Optional[WindowSize] = None,
     ):
         self._driver_type = driver_type
         self._window: WindowSize = window or (800, 600)
         self._screenshot_locate_wait = current_app.config["SCREENSHOT_LOCATE_WAIT"]
         self._screenshot_load_wait = current_app.config["SCREENSHOT_LOAD_WAIT"]
 
     def create(self) -> WebDriver:
+        pixel_density = current_app.config["WEBDRIVER_WINDOW"].get(
+            "pixel_density", 1)
         if self._driver_type == "firefox":
             driver_class = firefox.webdriver.WebDriver
             options = firefox.options.Options()
+            profile = FirefoxProfile()
+            profile.set_preference(
+                "layout.css.devPixelsPerPx",
+                str(pixel_density),
+            )
+            kwargs: Dict[Any, Any] = dict(
+                options=options, firefox_profile=profile)
         elif self._driver_type == "chrome":
             driver_class = chrome.webdriver.WebDriver
             options = chrome.options.Options()
-            options.add_argument(f"--window-size={self._window[0]},{self._window[1]}")
+            options.add_argument(
+                f"--force-device-scale-factor={pixel_density}")
+            options.add_argument(
+                f"--window-size={self._window[0]},{self._window[1]}")
+            kwargs = dict(options=options)
         else:
-            raise Exception(f"Webdriver name ({self._driver_type}) not supported")
+            raise Exception(
+                f"Webdriver name ({self._driver_type}) not supported")
         # Prepare args for the webdriver init
 
         # Add additional configured options
         for arg in current_app.config["WEBDRIVER_OPTION_ARGS"]:
             options.add_argument(arg)
 
-        kwargs: Dict[Any, Any] = dict(options=options)
         kwargs.update(current_app.config["WEBDRIVER_CONFIGURATION"])
         logger.info("Init selenium driver")
 
@@ -102,7 +117,10 @@ def destroy(driver: WebDriver, tries: int = 2) -> None:
             pass
 
     def get_screenshot(
-        self, url: str, element_name: str, user: "User",
+        self,
+        url: str,
+        element_name: str,
+        user: "User",
     ) -> Optional[bytes]:
         params = {"standalone": DashboardStandaloneMode.REPORT.value}
         req = PreparedRequest()
@@ -135,12 +153,14 @@ def get_screenshot(
             selenium_animation_wait = current_app.config[
                 "SCREENSHOT_SELENIUM_ANIMATION_WAIT"
             ]
-            logger.debug("Wait %i seconds for chart animation", selenium_animation_wait)
+            logger.debug("Wait %i seconds for chart animation",
+                         selenium_animation_wait)
             sleep(selenium_animation_wait)
             logger.info("Taking a PNG screenshot of url %s", url)
             img = element.screenshot_as_png
         except TimeoutException:
-            logger.warning("Selenium timed out requesting url %s", url, exc_info=True)
+            logger.warning(
+                "Selenium timed out requesting url %s", url, exc_info=True)
             img = element.screenshot_as_png
         except StaleElementReferenceException:
             logger.error(
@@ -151,5 +171,6 @@ def get_screenshot(
         except WebDriverException as ex:
             logger.error(ex, exc_info=True)
         finally:
-            self.destroy(driver, current_app.config["SCREENSHOT_SELENIUM_RETRIES"])
+            self.destroy(
+                driver, current_app.config["SCREENSHOT_SELENIUM_RETRIES"])
         return img