Databricks and CoCalc Renderers (#1703)

* Added CoCalc and Databricks renderers

* Update databricks renderer to search parent frames for displayHTML
function. Enable the renderer based on presence of an environment variable since
this displayHTML function search takes a bit of time and we don't want
to run it on import.

packages/python/plotly/plotly/io/_base_renderers.py

@@ -532,13 +532,15 @@ def __init__(
         post_script=None,
         animation_opts=None,
         include_plotlyjs=True,
+        html_directory="iframe_figures",
     ):
 
         self.config = config
         self.auto_play = auto_play
         self.post_script = post_script
         self.animation_opts = animation_opts
         self.include_plotlyjs = include_plotlyjs
+        self.html_directory = html_directory
 
     def to_mimebundle(self, fig_dict):
         from plotly.io import write_html
@@ -559,15 +561,10 @@ def to_mimebundle(self, fig_dict):
             iframe_height = str(525 + iframe_buffer) + "px"
 
         # Build filename using ipython cell number
-        ip = IPython.get_ipython()
-        cell_number = list(ip.history_manager.get_tail(1))[0][1] + 1
-        dirname = "iframe_figures"
-        filename = "{dirname}/figure_{cell_number}.html".format(
-            dirname=dirname, cell_number=cell_number
-        )
+        filename = self.build_filename()
 
         # Make directory for
-        os.makedirs(dirname, exist_ok=True)
+        os.makedirs(self.html_directory, exist_ok=True)
 
         write_html(
             fig_dict,
@@ -595,11 +592,38 @@ def to_mimebundle(self, fig_dict):
     allowfullscreen
 ></iframe>
 """.format(
-            width=iframe_width, height=iframe_height, src=filename
+            width=iframe_width, height=iframe_height, src=self.build_url(filename)
         )
 
         return {"text/html": iframe_html}
 
+    def build_filename(self):
+        ip = IPython.get_ipython()
+        cell_number = list(ip.history_manager.get_tail(1))[0][1] + 1
+        filename = "{dirname}/figure_{cell_number}.html".format(
+            dirname=self.html_directory, cell_number=cell_number
+        )
+        return filename
+
+    def build_url(self, filename):
+        return filename
+
+
+class CoCalcRenderer(IFrameRenderer):
+
+    _render_count = 0
+
+    def build_filename(self):
+        filename = "{dirname}/figure_{render_count}.html".format(
+            dirname=self.html_directory, render_count=CoCalcRenderer._render_count
+        )
+
+        CoCalcRenderer._render_count += 1
+        return filename
+
+    def build_url(self, filename):
+        return "{filename}?fullscreen=kiosk".format(filename=filename)
+
 
 class ExternalRenderer(BaseRenderer):
     """
@@ -707,6 +731,66 @@ def render(self, fig_dict):
         open_html_in_browser(html, self.using, self.new, self.autoraise)
 
 
+class DatabricksRenderer(ExternalRenderer):
+    def __init__(
+        self,
+        config=None,
+        auto_play=False,
+        post_script=None,
+        animation_opts=None,
+        include_plotlyjs="cdn",
+    ):
+
+        self.config = config
+        self.auto_play = auto_play
+        self.post_script = post_script
+        self.animation_opts = animation_opts
+        self.include_plotlyjs = include_plotlyjs
+        self._displayHTML = None
+
+    @property
+    def displayHTML(self):
+        import inspect
+
+        if self._displayHTML is None:
+            for frame in inspect.getouterframes(inspect.currentframe()):
+                global_names = set(frame.frame.f_globals)
+                # Check for displayHTML plus a few others to reduce chance of a false
+                # hit.
+                if all(v in global_names for v in ["displayHTML", "display", "spark"]):
+                    self._displayHTML = frame.frame.f_globals["displayHTML"]
+                    break
+
+            if self._displayHTML is None:
+                raise EnvironmentError(
+                    """
+Unable to detect the Databricks displayHTML function. The 'databricks' renderer is only
+supported when called from within the Databricks notebook environment."""
+                )
+
+        return self._displayHTML
+
+    def render(self, fig_dict):
+        from plotly.io import to_html
+
+        html = to_html(
+            fig_dict,
+            config=self.config,
+            auto_play=self.auto_play,
+            include_plotlyjs=self.include_plotlyjs,
+            include_mathjax="cdn",
+            post_script=self.post_script,
+            full_html=True,
+            animation_opts=self.animation_opts,
+            default_width="100%",
+            default_height="100%",
+            validate=False,
+        )
+
+        # displayHTML is a Databricks notebook built-in function
+        self.displayHTML(html)
+
+
 class SphinxGalleryRenderer(ExternalRenderer):
     def render(self, fig_dict):
         stack = inspect.stack()

packages/python/plotly/plotly/io/_renderers.py

@@ -25,6 +25,8 @@
     BrowserRenderer,
     IFrameRenderer,
     SphinxGalleryRenderer,
+    CoCalcRenderer,
+    DatabricksRenderer,
 )
 from plotly.io._utils import validate_coerce_fig_to_dict
 
@@ -406,6 +408,8 @@ def show(fig, renderer=None, validate=True, **kwargs):
 renderers["kaggle"] = KaggleRenderer(config=config)
 renderers["azure"] = AzureRenderer(config=config)
 renderers["colab"] = ColabRenderer(config=config)
+renderers["cocalc"] = CoCalcRenderer()
+renderers["databricks"] = DatabricksRenderer()
 
 # JSON
 renderers["json"] = JsonRenderer()
@@ -475,6 +479,13 @@ def show(fig, renderer=None, validate=True, **kwargs):
     if not default_renderer and "NTERACT_EXE" in os.environ:
         default_renderer = "nteract"
 
+    # Check if we're running in CoCalc
+    if not default_renderer and "COCALC_PROJECT_ID" in os.environ:
+        default_renderer = "cocalc"
+
+    if not default_renderer and "DATABRICKS_RUNTIME_VERSION" in os.environ:
+        default_renderer = "databricks"
+
     # Check if we're running in spyder and orca is installed
     if not default_renderer and "SPYDER_ARGS" in os.environ:
         try: