Remove plotly dep and make import optional.

Author: ayjayt

src/py/kaleido/kaleido.py

@@ -12,10 +12,8 @@
 
 import choreographer as choreo
 import logistro
-from choreographer import channels
 from choreographer.errors import ChromeNotFoundError
 from choreographer.utils import TmpDirectory
-from plotly.utils import PlotlyJSONEncoder
 
 from ._fig_tools import _is_figurish, build_fig_spec
 from ._kaleido_tab import _KaleidoTab
@@ -30,7 +28,14 @@
 
 _logger = logistro.getLogger(__name__)
 
-channels.register_custom_encoder(PlotlyJSONEncoder)
+try:
+    from choreographer import channels
+    from plotly.utils import PlotlyJSONEncoder
+
+    channels.register_custom_encoder(PlotlyJSONEncoder)
+    _logger.debug("Successfully registered PlotlyJSONEncoder.")
+except ImportError:
+    _logger.debug("Couldn't import plotly- skipping.")
 
 # Show a warning if the installed Plotly version
 # is incompatible with this version of Kaleido

src/py/pyproject.toml

@@ -30,7 +30,6 @@ dependencies = [
   "logistro>=1.0.8",
   "orjson>=3.10.15",
   "packaging",
-  "plotly>=6.3.0",
   "pytest-timeout>=2.4.0",
 ]