Merge pull request #20 from tpvasconcelos/lazy-colormap

🔧  Lazy load `PLOTLY_COLORSCALES` from `colors.json`

.gitignore

@@ -5,67 +5,34 @@
 # add custom entries here...
 
 
+# PyCharm  ---
+# exclude everything under
+.idea/*
+# except for...
+!.idea/ridgeplot.iml
+
+
 # ============================================================================
 #  My custom additions missing from
 #  https://github.com/github/gitignore (see bellow)
 # ============================================================================
 
-# Virtual environments  ---
-envs/
-venvs/
-pyvenv.cfg
-pip-selfcheck.json
-
-# poetry  ---
-poetry.lock
-
 # celery  ---
 **/celery*.log
 **/celery*.pid
 
 # dynaconf  ---
 **/*.local*
 
-# Pycharm  ---
-*.iml
-modules.xml
-*.ipr
-
 # System files  ---
 Desktop.ini
 Thumbs.db
 
-# Misc  ---
-# TODO: what is this?
-vcs.xml
-# .ssh/id_rsa
-id_rsa
-
 
 # ============================================================================
 #  Templates from https://github.com/github/gitignore
 # ============================================================================
 
-# Unused templates  ---
-# https://github.com/github/gitignore/blob/master/VisualStudio.gitignore
-# https://github.com/github/gitignore/blob/master/Swift.gitignore
-# https://github.com/github/gitignore/blob/master/Ruby.gitignore
-# https://github.com/github/gitignore/blob/master/Rails.gitignore
-# https://github.com/github/gitignore/blob/master/R.gitignore
-# https://github.com/github/gitignore/blob/master/Qt.gitignore
-# https://github.com/github/gitignore/blob/master/Node.gitignore
-# https://github.com/github/gitignore/blob/master/Julia.gitignore
-# https://github.com/github/gitignore/blob/master/Jekyll.gitignore
-# https://github.com/github/gitignore/blob/master/Go.gitignore
-# https://github.com/github/gitignore/blob/master/GitBook.gitignore
-# https://github.com/github/gitignore/blob/master/Fortran.gitignore
-# https://github.com/github/gitignore/blob/master/Dart.gitignore
-# https://github.com/github/gitignore/blob/master/CUDA.gitignore
-# https://github.com/github/gitignore/blob/master/CMake.gitignore
-# https://github.com/github/gitignore/blob/master/C.gitignore
-# https://github.com/github/gitignore/blob/master/C%2B%2B.gitignore
-# https://github.com/github/gitignore/blob/master/Terraform.gitignore
-
 # macOS  ---
 # ---> https://github.com/github/gitignore/blob/master/Global/macOS.gitignore
 # General
@@ -91,27 +58,6 @@ Network Trash Folder
 Temporary Items
 .apdisk
 
-# JetBrains  ---
-# ---> https://github.com/github/gitignore/blob/master/Global/JetBrains.gitignore
-# ---> https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
-.idea/
-# CMake
-cmake-build-*/
-# File-based project format
-*.iws
-# IntelliJ
-out/
-# JIRA plugin
-atlassian-ide-plugin.xml
-# Crashlytics plugin (for Android Studio and IntelliJ)
-com_crashlytics_export_strings.xml
-crashlytics.properties
-crashlytics-build.properties
-fabric.properties
-# Editor-based Rest Client
-.idea/httpRequests
-
-
 # Python  ---
 # ---> https://github.com/github/gitignore/blob/master/Python.gitignore
 # ---> https://github.com/github/gitignore/blob/master/community/Python/JupyterNotebooks.gitignore
@@ -227,13 +173,6 @@ dmypy.json
 .pytype/
 # Cython debug symbols
 cython_debug/
-# Jupyter
-.ipynb_checkpoints
-*/.ipynb_checkpoints/*
-# IPython
-profile_default/
-ipython_config.py
-
 
 # Archives  ---
 # ---> https://github.com/github/gitignore/blob/master/Global/Archives.gitignore
@@ -260,7 +199,6 @@ ipython_config.py
 *.dmg
 *.xpi
 *.gem
-*.egg
 *.deb
 *.rpm
 *.msi

CHANGES.md

@@ -6,7 +6,8 @@ This document outlines the list of changes to ridgeplot between each release. Fo
 Unreleased changes
 ------------------
 
-- ...
+- 🔧 Implement `LazyMapping` helper to allow `ridgeplot._colors.PLOTLY_COLORSCALES` to lazy-load from
+  `colors.json` ([#20](https://github.com/tpvasconcelos/ridgeplot/pull/20))
 
 0.1.14
 ------

ridgeplot/_colors.py

@@ -1,28 +1,51 @@
 import json
-from numbers import Number
 from pathlib import Path
-from typing import Dict, List, Union
+from typing import Dict, List, Tuple, Union
 
+from _plotly_utils.colors import validate_colors, validate_scale_values
 from plotly.colors import find_intermediate_color, hex_to_rgb, label_rgb
 
-from ridgeplot._utils import normalise
+from ridgeplot._utils import LazyMapping, normalise
+from ridgeplot.exceptions import InvalidColorscaleError
 
-# Ideally: ColorScaleType = List[Tuple[Number, str]]
-ColorScaleType = List[List[Union[Number, str]]]
+ColorScaleType = List[Tuple[float, str]]
+ColorScaleMappingType = Dict[str, ColorScaleType]
 
-# Load all plotly colorscales
-_path_to_colors_dict = Path(__file__).parent.joinpath("colors.json")
-PLOTLY_COLORSCALES: Dict[str, ColorScaleType] = json.loads(_path_to_colors_dict.read_text())
+
+def _colormap_loader() -> ColorScaleMappingType:
+    _path_to_colors_dict = Path(__file__).parent.joinpath("colors.json")
+    colors: dict = json.loads(_path_to_colors_dict.read_text())
+    for name, colorscale in colors.items():
+        colors[name] = [tuple(entry) for entry in colorscale]
+    return colors
+
+
+PLOTLY_COLORSCALES = LazyMapping(loader=_colormap_loader)
+
+
+def validate_colorscale(colorscale: ColorScaleType) -> None:
+    """Validate the structure, scale values, and colors of colorscale.
+
+    Adapted from ``_plotly_utils.colors.validate_colorscale``, changing the
+    requirement that a colorscale must be a list of tuples instead of a list of
+    lists.
+    """
+    if not isinstance(colorscale, list):
+        raise InvalidColorscaleError("A valid colorscale must be a list.")
+    if not all(isinstance(inner_tuple, tuple) for inner_tuple in colorscale):
+        raise InvalidColorscaleError("A valid colorscale must be a list.")
+    scale, colors = zip(*colorscale)
+    validate_scale_values(scale=scale)
+    validate_colors(colors=colors)
 
 
 def _any_to_rgb(color: Union[tuple, str]) -> str:
-    if isinstance(color, tuple):
-        color = label_rgb(color)
-    if color.startswith("#"):
-        color = label_rgb(hex_to_rgb(color))
-    if not color.startswith("rgb("):
+    c: str = label_rgb(color) if isinstance(color, tuple) else color
+    if c.startswith("#"):
+        c = label_rgb(hex_to_rgb(c))
+    if not c.startswith("rgb("):
         raise RuntimeError("Something went wrong with the logic above!")
-    return color
+    return c
 
 
 def get_plotly_colorscale(name: str) -> ColorScaleType:
@@ -49,7 +72,7 @@ def get_color(colorscale: ColorScaleType, midpoint: float) -> str:
     ceil = min(filter(lambda s: s > midpoint, scale))
     floor = max(filter(lambda s: s < midpoint, scale))
     midpoint_normalised = normalise(midpoint, min_=floor, max_=ceil)
-    color = find_intermediate_color(
+    color: str = find_intermediate_color(
         lowcolor=colors[scale.index(floor)],
         highcolor=colors[scale.index(ceil)],
         intermed=midpoint_normalised,
@@ -58,6 +81,6 @@ def get_color(colorscale: ColorScaleType, midpoint: float) -> str:
     return color
 
 
-def apply_alpha(color: Union[tuple, str], alpha) -> str:
+def apply_alpha(color: Union[tuple, str], alpha: float) -> str:
     color = _any_to_rgb(color)
     return f"rgba({color[4:-1]}, {alpha})"

ridgeplot/_figure_factory.py

@@ -1,14 +1,14 @@
 from typing import Callable, Dict, List, Optional
 
 import numpy as np
-from _plotly_utils.colors import validate_colorscale
 from plotly import graph_objects as go
 
 from ridgeplot._colors import (
     ColorScaleType,
     apply_alpha,
     get_color,
     get_plotly_colorscale,
+    validate_colorscale,
 )
 from ridgeplot._utils import get_extrema_3d, normalise
 

ridgeplot/_utils.py

@@ -1,15 +1,16 @@
-from typing import List, Tuple
+from typing import Callable, Iterator, List, Mapping, Optional, Tuple, TypeVar
 
 import numpy as np
+import numpy.typing as npt
 
 
-def get_extrema_2d(arr) -> Tuple[float, float]:
+def get_extrema_2d(arr: npt.ArrayLike) -> Tuple[float, float]:
     """Calculates and returns the extrema (min, max) of a 2D (N, M) array."""
     arr = np.asarray(arr).flat
     return np.min(arr), np.max(arr)
 
 
-def get_extrema_3d(arr: List[np.ndarray]) -> Tuple[float, float, float, float]:
+def get_extrema_3d(arr: List[npt.ArrayLike]) -> Tuple[float, float, float, float]:
     """Calculates and returns the x-y extrema (x_min, x_max, y_min, y_max) of
     a 3D (N, 2, M) array."""
     x_min = 0
@@ -27,3 +28,34 @@ def get_extrema_3d(arr: List[np.ndarray]) -> Tuple[float, float, float, float]:
 def normalise(val: float, min_: float, max_: float) -> float:
     assert max_ > min_
     return (val - min_) / (max_ - min_)
+
+
+KT = TypeVar("KT")  # Mapping key type
+VT = TypeVar("VT")  # Mapping value type
+
+
+class LazyMapping(Mapping[KT, VT]):
+    def __init__(self, loader: Callable[[], Mapping[KT, VT]]):
+        self._loader = loader
+        self._inner_mapping: Optional[Mapping[KT, VT]] = None
+
+    @property
+    def _mapping(self) -> Mapping[KT, VT]:
+        if self._inner_mapping is None:
+            self._inner_mapping = self._loader()
+        return self._inner_mapping
+
+    def __getitem__(self, item: KT) -> VT:
+        return self._mapping.__getitem__(item)
+
+    def __iter__(self) -> Iterator[KT]:
+        return self._mapping.__iter__()
+
+    def __len__(self) -> int:
+        return self._mapping.__len__()
+
+    def __str__(self) -> str:
+        return self._mapping.__str__()
+
+    def __repr__(self) -> str:
+        return self._mapping.__repr__()

ridgeplot/exceptions.py

@@ -0,0 +1,6 @@
+class RidgeplotError(Exception):
+    """Base ridgeplot exception."""
+
+
+class InvalidColorscaleError(RidgeplotError):
+    """Invalid format or type for colorscale."""

tests/conftest.py

@@ -1,15 +1,20 @@
+from typing import Any, Dict
+
 from pytest import Session
 
 
 def _patch_plotly_show() -> None:
     """Monkey patch ``plotly.io.show`` as to not perform any rendering and,
     instead, simply call ``plotly.io._utils.validate_coerce_fig_to_dict``"""
-    import plotly.io
+    from typing import Union
 
-    # noinspection PyProtectedMember
-    from plotly.io._utils import validate_coerce_fig_to_dict
+    import plotly.io
+    from plotly.graph_objs import Figure
+    from plotly.io._utils import validate_coerce_fig_to_dict  # noqa
 
-    def wrapped(fig, renderer=None, validate=True, **kwargs):
+    def wrapped(
+        fig: Union[Figure, dict], renderer: str = None, validate: bool = True, **kwargs: Dict[str, Any]
+    ) -> None:
         validate_coerce_fig_to_dict(fig, validate)
 
     plotly.io.show = wrapped

tests/unit/test_colors.py

@@ -0,0 +1,9 @@
+from ridgeplot._colors import PLOTLY_COLORSCALES, validate_colorscale
+from ridgeplot._utils import LazyMapping
+
+
+def test_plotly_colorscales() -> None:
+    assert isinstance(PLOTLY_COLORSCALES, LazyMapping)
+    for name, colorscale in PLOTLY_COLORSCALES.items():
+        assert isinstance(name, str)
+        validate_colorscale(colorscale=colorscale)