Source code for panel.pane.deckgl

"""
Defines a PyDeck Pane which renders a PyDeck plot using a PyDeckPlot
bokeh model.
"""
from __future__ import annotations

import json
import sys

from collections import defaultdict
from typing import (
    TYPE_CHECKING, Any, ClassVar, Mapping, Optional,
)

import numpy as np
import param

from bokeh.models import ColumnDataSource
from pyviz_comms import JupyterComm

from ..util import is_dataframe, lazy_load
from ..viewable import Layoutable
from .base import PaneBase

if TYPE_CHECKING:
    from bokeh.document import Document
    from bokeh.model import Model
    from pyviz_comms import Comm


[docs]def lower_camel_case_keys(attrs): """ Makes all the keys in a dictionary camel-cased and lower-case Parameters ---------- attrs : dict Dictionary for which all the keys should be converted to camel-case """ for snake_key in list(attrs.keys()): if '_' not in snake_key: continue camel_key = lower_first_letter(to_camel_case(snake_key)) attrs[camel_key] = attrs.pop(snake_key)
[docs]def to_camel_case(snake_case: str) -> str: """ Makes a snake case string into a camel case one Parameters ----------- snake_case : str Snake-cased string (e.g., "snake_cased") to be converted to camel-case (e.g., "camelCase") """ output_str = '' should_upper_case = False for c in snake_case: if c == '_': should_upper_case = True continue output_str = output_str + c.upper() if should_upper_case else output_str + c should_upper_case = False return output_str
def lower_first_letter(s: str) -> str: return s[:1].lower() + s[1:] if s else '' def recurse_data(data): if hasattr(data, 'to_json'): data = data.__dict__ if isinstance(data, dict): data = dict(data) lower_camel_case_keys(data) data = {k: recurse_data(v) if k != 'data' else v for k, v in data.items()} elif isinstance(data, list): data = [recurse_data(d) for d in data] return data
[docs]class DeckGL(PaneBase): """ The `DeckGL` pane renders the Deck.gl JSON specification as well as PyDeck plots inside a panel. Deck.gl is a very powerful WebGL-powered framework for visual exploratory data analysis of large datasets. Reference: https://panel.holoviz.org/reference/panes/DeckGL.html :Example: >>> pn.extension('deckgl') >>> DeckGL( ... some_deckgl_dict_or_pydeck_object, ... mapbox_api_key=MAPBOX_KEY, height=600 ... ) """ mapbox_api_key = param.String(default=None, doc=""" The MapBox API key if not supplied by a PyDeck object.""") tooltips = param.ClassSelector(default=True, class_=(bool, dict), doc=""" Whether to enable tooltips""") click_state = param.Dict(default={}, doc=""" Contains the last click event on the DeckGL plot.""") hover_state = param.Dict(default={}, doc=""" The current hover state of the DeckGL plot.""") view_state = param.Dict(default={}, doc=""" The current view state of the DeckGL plot.""") throttle = param.Dict(default={'view': 200, 'hover': 200}, doc=""" Throttling timeout (in milliseconds) for view state and hover events sent from the frontend.""") _rename: ClassVar[Mapping[str, str | None]] = { 'click_state': 'clickState', 'hover_state': 'hoverState', 'view_state': 'viewState', 'tooltips': 'tooltip' } _updates: ClassVar[bool] = True priority: ClassVar[float | bool | None] = None
[docs] @classmethod def applies(cls, obj: Any) -> float | bool | None: if cls.is_pydeck(obj): return 0.8 elif isinstance(obj, (dict, str)): return 0 return False
@classmethod def is_pydeck(cls, obj): if 'pydeck' in sys.modules: import pydeck return isinstance(obj, pydeck.bindings.deck.Deck) return False def _get_properties(self, layout: bool = True): if self.object is None: data, mapbox_api_key, tooltip = {}, self.mapbox_api_key, self.tooltips elif isinstance(self.object, (str, dict)): if isinstance(self.object, str): data = json.loads(self.object) else: data = dict(self.object) data['layers'] = [dict(layer) for layer in data.get('layers', [])] mapbox_api_key = self.mapbox_api_key tooltip = self.tooltips else: data = dict(self.object.__dict__) mapbox_api_key = data.pop('mapbox_key', self.mapbox_api_key) deck_widget = data.pop('deck_widget', None) tooltip = self.tooltips if isinstance(self.tooltips, dict) else deck_widget.tooltip data = {k: v for k, v in recurse_data(data).items() if v is not None} # Delete undefined width and height for view in data.get('views', []): if view.get('width', False) is None: view.pop('width') if view.get('height', False) is None: view.pop('height') if layout: properties = {p: getattr(self, p) for p in Layoutable.param if getattr(self, p) is not None} else: properties = {} return data, dict(properties, tooltip=tooltip, mapbox_api_key=mapbox_api_key or "") @classmethod def _process_data(cls, data): columns = defaultdict(list) for d in data: for col, val in d.items(): columns[col].append(val) return {col: np.asarray(vals) for col, vals in columns.items()} @classmethod def _update_sources(cls, json_data, sources): layers = json_data.get('layers', []) # Create index of sources by columns source_columns = defaultdict(list) for i, source in enumerate(sources): key = tuple(sorted(source.data.keys())) source_columns[key].append((i, source)) # Process unprocessed, unused = [], list(sources) for layer in layers: data = layer.get('data') if is_dataframe(data): data = ColumnDataSource.from_df(data) elif (isinstance(data, list) and data and isinstance(data[0], dict)): data = cls._process_data(data) else: continue key = tuple(sorted(data.keys())) existing = source_columns.get(key) if existing: index, cds = existing.pop() layer['data'] = index updates = {} for col, values in data.items(): if not np.array_equal(data[col], cds.data[col]): updates[col] = values if updates: cds.data.update(updates) unused.remove(cds) else: unprocessed.append((layer, data)) for layer, data in unprocessed: if unused: cds = unused.pop() cds.data = data else: cds = ColumnDataSource(data) sources.append(cds) layer['data'] = sources.index(cds) def _get_model( self, doc: Document, root: Optional[Model] = None, parent: Optional[Model] = None, comm: Optional[Comm] = None ) -> Model: DeckGLPlot = lazy_load( 'panel.models.deckgl', 'DeckGLPlot', isinstance(comm, JupyterComm), root ) data, properties = self._get_properties() properties['data_sources'] = sources = [] self._update_sources(data, sources) properties['layers'] = data.pop('layers', []) properties['initialViewState'] = data.pop('initialViewState', {}) model = DeckGLPlot(data=data, **properties) root = root or model self._link_props(model, ['clickState', 'hoverState', 'viewState'], doc, root, comm) self._models[root.ref["id"]] = (model, parent) return model def _update(self, ref: str, model: Model) -> None: data, properties = self._get_properties(layout=False) self._update_sources(data, model.data_sources) properties['data'] = data properties['layers'] = data.pop('layers', []) properties['initialViewState'] = data.pop('initialViewState', {}) model.update(**properties)