small io refactor to support kaleido v1

Author: emilykl

plotly/io/_kaleido.py

@@ -1,29 +1,41 @@
 import os
 import json
 from pathlib import Path
+import importlib.metadata as importlib_metadata
+from packaging.version import Version
+import tempfile
+
 import plotly
 from plotly.io._utils import validate_coerce_fig_to_dict
 
 try:
-    from kaleido.scopes.plotly import PlotlyScope
-
-    scope = PlotlyScope()
-
-    # Compute absolute path to the 'plotly/package_data/' directory
-    root_dir = os.path.dirname(os.path.abspath(plotly.__file__))
-    package_dir = os.path.join(root_dir, "package_data")
-    scope.plotlyjs = os.path.join(package_dir, "plotly.min.js")
-    if scope.mathjax is None:
-        scope.mathjax = (
-            "https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.5/MathJax.js"
-        )
-except ImportError:
+    import kaleido
+
+    kaleido_available = True
+    kaleido_major = Version(importlib_metadata.version("kaleido")).major
+
+    if kaleido_major < 1:
+        # Kaleido v0
+        from kaleido.scopes.plotly import PlotlyScope
+
+        scope = PlotlyScope()
+        # Compute absolute path to the 'plotly/package_data/' directory
+        root_dir = os.path.dirname(os.path.abspath(plotly.__file__))
+        package_dir = os.path.join(root_dir, "package_data")
+        scope.plotlyjs = os.path.join(package_dir, "plotly.min.js")
+        if scope.mathjax is None:
+            scope.mathjax = (
+                "https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.5/MathJax.js"
+            )
+except ImportError as e:
+    kaleido_available = False
+    kaleido_major = -1
     PlotlyScope = None
     scope = None
 
 
 def to_image(
-    fig, format=None, width=None, height=None, scale=None, validate=True, engine="auto"
+    fig, format=None, width=None, height=None, scale=None, validate=True, engine=None
 ):
     """
     Convert a figure to a static image bytes string
@@ -35,100 +47,52 @@ def to_image(
 
     format: str or None
         The desired image format. One of
-          - 'png'
-          - 'jpg' or 'jpeg'
-          - 'webp'
-          - 'svg'
-          - 'pdf'
-          - 'eps' (Requires the poppler library to be installed and on the PATH)
+            - 'png'
+            - 'jpg' or 'jpeg'
+            - 'webp'
+            - 'svg'
+            - 'pdf'
+            - 'eps' (Requires the poppler library to be installed and on the PATH)
 
-        If not specified, will default to:
-             - `plotly.io.kaleido.scope.default_format` if engine is "kaleido"
-             - `plotly.io.orca.config.default_format` if engine is "orca"
+        If not specified, will default to `plotly.io.kaleido.scope.default_format`
 
     width: int or None
         The width of the exported image in layout pixels. If the `scale`
         property is 1.0, this will also be the width of the exported image
         in physical pixels.
 
-        If not specified, will default to:
-             - `plotly.io.kaleido.scope.default_width` if engine is "kaleido"
-             - `plotly.io.orca.config.default_width` if engine is "orca"
+        If not specified, will default to `plotly.io.kaleido.scope.default_width`
 
     height: int or None
         The height of the exported image in layout pixels. If the `scale`
         property is 1.0, this will also be the height of the exported image
         in physical pixels.
 
-        If not specified, will default to:
-             - `plotly.io.kaleido.scope.default_height` if engine is "kaleido"
-             - `plotly.io.orca.config.default_height` if engine is "orca"
+        If not specified, will default to `plotly.io.kaleido.scope.default_height`
 
     scale: int or float or None
         The scale factor to use when exporting the figure. A scale factor
         larger than 1.0 will increase the image resolution with respect
         to the figure's layout pixel dimensions. Whereas as scale factor of
         less than 1.0 will decrease the image resolution.
 
-        If not specified, will default to:
-             - `plotly.io.kaleido.scope.default_scale` if engine is "kaleido"
-             - `plotly.io.orca.config.default_scale` if engine is "orca"
-
+        If not specified, will default to `plotly.io.kaleido.scope.default_scale`
 
     validate: bool
         True if the figure should be validated before being converted to
         an image, False otherwise.
 
-    engine: str
-        Image export engine to use:
-         - "kaleido": Use Kaleido for image export
-         - "orca": Use Orca for image export
-         - "auto" (default): Use Kaleido if installed, otherwise use orca
+    engine (deprecated): str
+        No longer used. Kaleido is the only supported engine.
 
     Returns
     -------
     bytes
         The image data
     """
-    # Handle engine
-    # -------------
-    if engine == "auto":
-        if scope is not None:
-            # Default to kaleido if available
-            engine = "kaleido"
-        else:
-            # See if orca is available
-            from ._orca import validate_executable
-
-            try:
-                validate_executable()
-                engine = "orca"
-            except:
-                # If orca not configured properly, make sure we display the error
-                # message advising the installation of kaleido
-                engine = "kaleido"
-
-    if engine == "orca":
-        # Fall back to legacy orca image export path
-        from ._orca import to_image as to_image_orca
-
-        return to_image_orca(
-            fig,
-            format=format,
-            width=width,
-            height=height,
-            scale=scale,
-            validate=validate,
-        )
-    elif engine != "kaleido":
-        raise ValueError(
-            "Invalid image export engine specified: {engine}".format(
-                engine=repr(engine)
-            )
-        )
 
     # Raise informative error message if Kaleido is not installed
-    if scope is None:
+    if not kaleido_available:
         raise ValueError(
             """
 Image export using the "kaleido" engine requires the kaleido package,
@@ -137,12 +101,32 @@ def to_image(
 """
         )
 
-    # Validate figure
-    # ---------------
+    # Convert figure to dict (and validate if requested)
     fig_dict = validate_coerce_fig_to_dict(fig, validate)
-    img_bytes = scope.transform(
-        fig_dict, format=format, width=width, height=height, scale=scale
-    )
+
+    # Request image bytes
+    if kaleido_major > 0:
+        # Kaleido v1
+        opts = {
+            k: v
+            for k, v in dict(
+                format=format,
+                width=width,
+                height=height,
+                scale=scale,
+            ).items()
+            if v is not None
+        }
+        img_bytes = kaleido.calc_fig_sync(
+            fig_dict,
+            path=None,
+            opts=opts,
+        )
+    else:
+        # Kaleido v0
+        img_bytes = scope.transform(
+            fig_dict, format=format, width=width, height=height, scale=scale
+        )
 
     return img_bytes
 
@@ -190,38 +174,29 @@ def write_image(
         property is 1.0, this will also be the width of the exported image
         in physical pixels.
 
-        If not specified, will default to:
-            - `plotly.io.kaleido.scope.default_width` if engine is "kaleido"
-            - `plotly.io.orca.config.default_width` if engine is "orca"
+        If not specified, will default to`plotly.io.kaleido.scope.default_width`
 
     height: int or None
         The height of the exported image in layout pixels. If the `scale`
         property is 1.0, this will also be the height of the exported image
         in physical pixels.
 
-        If not specified, will default to:
-            - `plotly.io.kaleido.scope.default_height` if engine is "kaleido"
-            - `plotly.io.orca.config.default_height` if engine is "orca"
+        If not specified, will default to `plotly.io.kaleido.scope.default_height`
 
     scale: int or float or None
         The scale factor to use when exporting the figure. A scale factor
         larger than 1.0 will increase the image resolution with respect
         to the figure's layout pixel dimensions. Whereas as scale factor of
         less than 1.0 will decrease the image resolution.
 
-        If not specified, will default to:
-            - `plotly.io.kaleido.scope.default_scale` if engine is "kaleido"
-            - `plotly.io.orca.config.default_scale` if engine is "orca"
+        If not specified, will default to `plotly.io.kaleido.scope.default_scale`
 
     validate: bool
         True if the figure should be validated before being converted to
         an image, False otherwise.
 
-    engine: str
-        Image export engine to use:
-         - "kaleido": Use Kaleido for image export
-         - "orca": Use Orca for image export
-         - "auto" (default): Use Kaleido if installed, otherwise use orca
+    engine (deprecated): str
+        No longer used. Kaleido is the only supported engine.
 
     Returns
     -------
@@ -323,7 +298,7 @@ def full_figure_for_development(fig, warn=True, as_dict=False):
     """
 
     # Raise informative error message if Kaleido is not installed
-    if scope is None:
+    if not kaleido_available:
         raise ValueError(
             """
 Full figure generation requires the kaleido package,
@@ -341,7 +316,24 @@ def full_figure_for_development(fig, warn=True, as_dict=False):
             "To suppress this warning, set warn=False"
         )
 
-    fig = json.loads(scope.transform(fig, format="json").decode("utf-8"))
+    if kaleido_major > 0:
+        # Kaleido v1
+        try:
+            json_file = Path(tempfile.mkstemp(suffix=".json")[1])
+            kaleido.write_fig_sync(
+                fig,
+                json_file,
+                dict(format="json"),
+            )
+            with open(json_file, "r") as f:
+                fig = json.load(f)
+        finally:
+            # Cleanup: remove temp file
+            json_file.unlink()
+    else:
+        # Kaleido v0
+        fig = json.loads(scope.transform(fig, format="json").decode("utf-8"))
+
     if as_dict:
         return fig
     else:

plotly/io/kaleido.py

@@ -1 +1 @@
-from ._kaleido import to_image, write_image, scope
+from ._kaleido import write_image, to_image