Implement Template.save

panel/io/save.py

@@ -7,6 +7,8 @@
 
 from six import string_types
 
+import bokeh
+
 from bokeh.document.document import Document
 from bokeh.embed import file_html
 from bokeh.io.export import export_png
@@ -23,8 +25,7 @@
 # Private API
 #---------------------------------------------------------------------
 
-
-def save_png(model, filename):
+def save_png(model, filename, template=None, template_variables=None):
     """
     Saves a bokeh model to png
 
@@ -34,13 +35,33 @@ def save_png(model, filename):
       Model to save to png
     filename: str
       Filename to save to
+    template:
+      template file, as used by bokeh.file_html. If None will use bokeh defaults
+    template_variables:
+      template_variables file dict, as used by bokeh.file_html
     """
     from bokeh.io.webdriver import webdriver_control
     if not state.webdriver:
         state.webdriver = webdriver_control.create()
 
     webdriver = state.webdriver
-    export_png(model, filename=filename, webdriver=webdriver)
+
+    try:
+        if template:
+            def get_layout_html(obj, resources, width, height):
+                return file_html(
+                    obj, resources, title="", template=template,
+                    template_variables=template_variables,
+                    suppress_callback_warning=True, _always_new=True
+                )
+            old_layout_fn = bokeh.io.export.get_layout_html
+            bokeh.io.export.get_layout_html = get_layout_html
+        export_png(model, filename=filename, webdriver=webdriver)
+    except Exception:
+        raise
+    finally:
+        if template:
+            bokeh.io.export.get_layout_html = old_layout_fn
 
 
 #---------------------------------------------------------------------
@@ -86,27 +107,38 @@ def save(panel, filename, title=None, resources=None, template=None,
       Whether to report progress
     """
     from ..pane import PaneBase
+    from ..template import Template
 
     if isinstance(panel, PaneBase) and len(panel.layout) > 1:
         panel = panel.layout
 
     as_png = isinstance(filename, string_types) and filename.endswith('png')
 
-    doc = Document()
+    if isinstance(panel, Document):
+        doc = panel
+    else:
+        doc = Document()
+
     comm = Comm()
     with config.set(embed=embed):
-        model = panel.get_root(doc, comm)
-        if embed:
-            embed_state(
-                panel, model, doc, max_states, max_opts, embed_json,
-                json_prefix, save_path, load_path, progress
-            )
+        if isinstance(panel, Document):
+            model = panel
+        elif isinstance(panel, Template):
+            panel._init_doc(doc, title=title)
+            model = doc
         else:
-            add_to_doc(model, doc, True)
+            model = panel.get_root(doc, comm)
+            if embed:
+                embed_state(
+                    panel, model, doc, max_states, max_opts, embed_json,
+                    json_prefix, save_path, load_path, progress
+                )
+            else:
+                add_to_doc(model, doc, True)
 
     if as_png:
-        save_png(model, filename=filename)
-        return
+        return save_png(model, filename=filename, template=template,
+                        template_variables=template_variables)
     elif isinstance(filename, string_types) and not filename.endswith('.html'):
         filename = filename + '.html'
 

panel/template.py

@@ -20,6 +20,7 @@
 from .config import config, panel_extension
 from .io.model import add_to_doc
 from .io.notebook import render_template
+from .io.save import save
 from .io.state import state
 from .layout import Column
 from .models.comm_manager import CommManager
@@ -67,7 +68,10 @@ class Template(param.Parameterized, ServableMixin):
     def __init__(self, template=None, items=None, nb_template=None, **params):
         super(Template, self).__init__(**params)
         if isinstance(template, string_types):
+            self._code = template
             template = _Template(template)
+        else:
+            self._code = None
         self.template = template
         if isinstance(nb_template, string_types):
             nb_template = _Template(nb_template)
@@ -244,3 +248,58 @@ def server_doc(self, doc=None, title=None):
           The Bokeh document the panel was attached to
         """
         return self._init_doc(doc, title=title)
+
+    def save(self, filename, title=None, resources=None, embed=False,
+             max_states=1000, max_opts=3, embed_json=False,
+             json_prefix='', save_path='./', load_path=None):
+        """
+        Saves Panel objects to file.
+
+        Arguments
+        ---------
+        filename: string or file-like object
+           Filename to save the plot to
+        title: string
+           Optional title for the plot
+        resources: bokeh resources
+           One of the valid bokeh.resources (e.g. CDN or INLINE)
+        embed: bool
+           Whether the state space should be embedded in the saved file.
+        max_states: int
+           The maximum number of states to embed
+        max_opts: int
+           The maximum number of states for a single widget
+        embed_json: boolean (default=True)
+           Whether to export the data to json files
+        json_prefix: str (default='')
+           Prefix for the auto-generated json directory
+        save_path: str (default='./')
+           The path to save json files to
+        load_path: str (default=None)
+           The path or URL the json files will be loaded from.
+        """
+        if embed:
+            raise ValueError("Embedding is not yet supported on Template.")
+        return save(self, filename, title, resources, self.template,
+                    self._render_variables, embed, max_states, max_opts,
+                    embed_json, json_prefix, save_path, load_path)
+
+    def select(self, selector=None):
+        """
+        Iterates over the Template and any potential children in the
+        applying the Selector.
+
+        Arguments
+        ---------
+        selector: type or callable or None
+          The selector allows selecting a subset of Viewables by
+          declaring a type or callable function to filter by.
+
+        Returns
+        -------
+        viewables: list(Viewable)
+        """
+        objects = []
+        for obj, _ in self._render_items.values():
+            objects += obj.select(selector)
+        return objects