from __future__ import absolute_import, print_function import logging logger = logging.getLogger(__file__) from json import loads from six import iteritems from .core.json_encoder import serialize_json from .core.properties import Any, HasProps, List, MetaHasProps, String from .core.query import find from .themes import default as default_theme from .util.callback_manager import CallbackManager from .util.future import with_metaclass from .util.serialization import make_id class Viewable(MetaHasProps): """ Any plot object (Data Model) which has its own View Model in the persistence layer. One thing to keep in mind is that a Viewable should have a single unique representation in the persistence layer, but it might have multiple concurrent client-side Views looking at it. Those may be from different machines altogether. """ # Stores a mapping from subclass __view_model__ names to classes model_class_reverse_map = {} # Mmmm.. metaclass inheritance. On the one hand, it seems a little # overkill. On the other hand, this is exactly the sort of thing # it's meant for. def __new__(meta_cls, class_name, bases, class_dict): if "__view_model__" not in class_dict: class_dict["__view_model__"] = class_name class_dict["get_class"] = Viewable.get_class # Create the new class newcls = super(Viewable, meta_cls).__new__(meta_cls, class_name, bases, class_dict) entry = class_dict.get("__subtype__", class_dict["__view_model__"]) # Add it to the reverse map, but check for duplicates first if entry in Viewable.model_class_reverse_map and not hasattr(newcls, "__implementation__"): raise Warning("Duplicate __view_model__ or __subtype__ declaration of '%s' for " \ "class %s. Previous definition: %s" % \ (entry, class_name, Viewable.model_class_reverse_map[entry])) Viewable.model_class_reverse_map[entry] = newcls return newcls @classmethod def _preload_models(cls): from . import models; models from .plotting import Figure; Figure try: from .charts import Chart; Chart except RuntimeError: # this would occur if pandas is not installed but then we can't # use the bokeh.charts interface anyway pass @classmethod def get_class(cls, view_model_name): """ Given a __view_model__ name, returns the corresponding class object """ cls._preload_models() d = Viewable.model_class_reverse_map if view_model_name in d: return d[view_model_name] else: raise KeyError("View model name '%s' not found" % view_model_name) class Model(with_metaclass(Viewable, HasProps, CallbackManager)): """ Base class for all plot-related objects """ name = String() tags = List(Any) def __init__(self, **kwargs): self._id = kwargs.pop("id", make_id()) self._document = None super(Model, self).__init__(**kwargs) default_theme.apply_to_model(self) def _attach_document(self, doc): '''This should only be called by the Document implementation to set the document field''' if self._document is not None and self._document is not doc: raise RuntimeError("Models must be owned by only a single document, %r is already in a doc" % (self)) self._document = doc doc.theme.apply_to_model(self) def _detach_document(self): '''This should only be called by the Document implementation to unset the document field''' self._document = None default_theme.apply_to_model(self) @property def document(self): return self._document def trigger(self, attr, old, new, hint=None): dirty = { 'count' : 0 } def mark_dirty(obj): dirty['count'] += 1 if self._document is not None: self._visit_value_and_its_immediate_references(new, mark_dirty) self._visit_value_and_its_immediate_references(old, mark_dirty) if dirty['count'] > 0: self._document._invalidate_all_models() # chain up to invoke callbacks super(Model, self).trigger(attr, old, new, hint) @property def ref(self): if "__subtype__" in self.__class__.__dict__: return { 'type': self.__view_model__, 'subtype': self.__subtype__, 'id': self._id, } else: return { 'type': self.__view_model__, 'id': self._id, } def select(self, selector): ''' Query this object and all of its references for objects that match the given selector. Args: selector (JSON-like) : Returns: seq[Model] ''' return find(self.references(), selector) def select_one(self, selector): ''' Query this object and all of its references for objects that match the given selector. Raises an error if more than one object is found. Returns single matching object, or None if nothing is found Args: selector (JSON-like) : Returns: Model ''' result = list(self.select(selector)) if len(result) > 1: raise ValueError("Found more than one object matching %s: %r" % (selector, result)) if len(result) == 0: return None return result[0] def set_select(self, selector, updates): ''' Update objects that match a given selector with the specified attribute/value updates. Args: selector (JSON-like) : updates (dict) : Returns: None ''' for obj in self.select(selector): for key, val in updates.items(): setattr(obj, key, val) def layout(self, side, plot): try: return self in getattr(plot, side) except: return [] @classmethod def _visit_immediate_value_references(cls, value, visitor): ''' Visit all references to another Model without recursing into any of the child Model; may visit the same Model more than once if it's referenced more than once. Does not visit the passed-in value. ''' if isinstance(value, HasProps): for attr in value.properties_with_refs(): child = getattr(value, attr) cls._visit_value_and_its_immediate_references(child, visitor) else: cls._visit_value_and_its_immediate_references(value, visitor) @classmethod def _visit_value_and_its_immediate_references(cls, obj, visitor): if isinstance(obj, Model): visitor(obj) elif isinstance(obj, HasProps): # this isn't a Model, so recurse into it cls._visit_immediate_value_references(obj, visitor) elif isinstance(obj, (list, tuple)): for item in obj: cls._visit_value_and_its_immediate_references(item, visitor) elif isinstance(obj, dict): for key, value in iteritems(obj): cls._visit_value_and_its_immediate_references(key, visitor) cls._visit_value_and_its_immediate_references(value, visitor) @classmethod def collect_models(cls, *input_values): """ Iterate over ``input_values`` and descend through their structure collecting all nested ``Models`` on the go. The resulting list is duplicate-free based on objects' identifiers. """ ids = set([]) collected = [] queued = [] def queue_one(obj): if obj._id not in ids: queued.append(obj) for value in input_values: cls._visit_value_and_its_immediate_references(value, queue_one) while queued: obj = queued.pop(0) if obj._id not in ids: ids.add(obj._id) collected.append(obj) cls._visit_immediate_value_references(obj, queue_one) return collected def references(self): """Returns all ``Models`` that this object has references to. """ return set(self.collect_models(self)) def _to_json_like(self, include_defaults): """ Returns a dictionary of the attributes of this object, in a layout corresponding to what BokehJS expects at unmarshalling time. This method does not convert "Bokeh types" into "plain JSON types," for example each child Model will still be a Model, rather than turning into a reference, numpy isn't handled, etc. That's what "json like" means. This method should be considered "private" or "protected", for use internal to Bokeh; use to_json() instead because it gives you only plain JSON-compatible types. Args: include_defaults (bool) : whether to include attributes that haven't been changed from the default. """ attrs = self.properties_with_values(include_defaults=include_defaults) for (k, v) in attrs.items(): # we can't serialize Infinity, we send it as None and # the other side has to fix it up. This transformation # can't be in our json_encoder because the json # module checks for inf before it calls the custom # encoder. if isinstance(v, float) and v == float('inf'): attrs[k] = None return attrs def to_json(self, include_defaults): """ Returns a dictionary of the attributes of this object, containing only "JSON types" (string, number, boolean, none, dict, list). References to other objects are serialized as "refs" (just the object ID and type info), so the deserializer will need to separately have the full attributes of those other objects. There's no corresponding from_json() because to deserialize an object is normally done in the context of a Document (since the Document can resolve references). For most purposes it's best to serialize and deserialize entire documents. Args: include_defaults (bool) : whether to include attributes that haven't been changed from the default """ return loads(self.to_json_string(include_defaults=include_defaults)) def to_json_string(self, include_defaults): """Returns a JSON string encoding the attributes of this object. References to other objects are serialized as references (just the object ID and type info), so the deserializer will need to separately have the full attributes of those other objects. There's no corresponding from_json_string() because to deserialize an object is normally done in the context of a Document (since the Document can resolve references). For most purposes it's best to serialize and deserialize entire documents. Args: include_defaults (bool) : whether to include attributes that haven't been changed from the default """ json_like = self._to_json_like(include_defaults=include_defaults) json_like['id'] = self._id # serialize_json "fixes" the JSON from _to_json_like by converting # all types into plain JSON types # (it converts Model into refs, # for example). return serialize_json(json_like) def __str__(self): return "%s, ViewModel:%s, ref _id: %s" % (self.__class__.__name__, self.__view_model__, getattr(self, "_id", None)) def _find_some_document(models): from .document import Document # First try the easy stuff... doc = None for model in models: if isinstance(model, Document): doc = model break elif isinstance(model, Model): if model.document is not None: doc = model.document break # Now look in children of models if doc is None: for model in models: if isinstance(model, Model): # see if some child of ours is in a doc, this is meant to # handle a thing like: # p = figure() # box = HBox(children=[p]) # show(box) for r in model.references(): if r.document is not None: doc = r.document break return doc class _ModelInDocument(object): # 'models' can be a single Model, a single Document, or a list of either def __init__(self, models): from .document import Document self._to_remove_after = [] if not isinstance(models, list): models = [models] self._doc = _find_some_document(models) if self._doc is None: # oh well - just make up a doc self._doc = Document() for model in models: if isinstance(model, Model): if model.document is None: self._to_remove_after.append(model) def __exit__(self, type, value, traceback): for model in self._to_remove_after: model.document.remove_root(model) def __enter__(self): for model in self._to_remove_after: self._doc.add_root(model)