bokeh.core.templates

Provide Jinja2 templates used by Bokeh to embed Bokeh models (e.g. plots, widgets, layouts) in various ways.

AUTOLOAD_JS = <Template 'autoload_js.js'>

Renders JavaScript code for “autoloading”.

The code automatically and asynchronously loads BokehJS (if necessary) and then replaces the AUTOLOAD_TAG <script> tag that calls it with the rendered model.

Parameters:
  • elementid (str) – the unique id for the script tag
  • js_urls (list) – URLs of JS files making up Bokeh library
  • css_urls (list) – CSS urls to inject
Template: autoload_js.js
(function(root) {
  function now() {
    return new Date();
  }

  var force = {{ force|default(False)|json }};

  if (typeof (root._bokeh_onload_callbacks) === "undefined" || force === true) {
    root._bokeh_onload_callbacks = [];
    root._bokeh_is_loading = undefined;
  }

  {% block register_mimetype %}
  {% endblock %}

  {% block autoload_init %}
  {% endblock %}

  function run_callbacks() {
    try {
      root._bokeh_onload_callbacks.forEach(function(callback) { callback() });
    }
    finally {
      delete root._bokeh_onload_callbacks
    }
    console.info("Bokeh: all callbacks have finished");
  }

  function load_libs(js_urls, callback) {
    root._bokeh_onload_callbacks.push(callback);
    if (root._bokeh_is_loading > 0) {
      console.log("Bokeh: BokehJS is being loaded, scheduling callback at", now());
      return null;
    }
    if (js_urls == null || js_urls.length === 0) {
      run_callbacks();
      return null;
    }
    console.log("Bokeh: BokehJS not loaded, scheduling load and callback at", now());
    root._bokeh_is_loading = js_urls.length;
    for (var i = 0; i < js_urls.length; i++) {
      var url = js_urls[i];
      var s = document.createElement('script');
      s.src = url;
      s.async = false;
      s.onreadystatechange = s.onload = function() {
        root._bokeh_is_loading--;
        if (root._bokeh_is_loading === 0) {
          console.log("Bokeh: all BokehJS libraries loaded");
          run_callbacks()
        }
      };
      s.onerror = function() {
        console.warn("failed to load library " + url);
      };
      console.log("Bokeh: injecting script tag for BokehJS library: ", url);
      document.getElementsByTagName("head")[0].appendChild(s);
    }
  };

  {%- if elementid -%}
  var element = document.getElementById({{ elementid|json }});
  if (element == null) {
    console.log("Bokeh: ERROR: autoload.js configured with elementid '{{ elementid }}' but no matching script tag was found. ")
    return false;
  }
  {%- endif %}

  var js_urls = {{ js_urls|json }};

  var inline_js = [
    {%- for js in js_raw %}
    function(Bokeh) {
      {{ js|indent(6) }}
    },
    {% endfor -%}
    function(Bokeh) {
      {%- for url in css_urls %}
      console.log("Bokeh: injecting CSS: {{ url }}");
      Bokeh.embed.inject_css({{ url|json }});
      {%- endfor %}
      {%- for css in css_raw %}
      console.log("Bokeh: injecting raw CSS");
      Bokeh.embed.inject_raw_css({{ css }});
      {%- endfor %}
    }
  ];

  function run_inline_js() {
    {% block run_inline_js %}
    for (var i = 0; i < inline_js.length; i++) {
      inline_js[i].call(root, root.Bokeh);
    }
    {% endblock %}
  }

  if (root._bokeh_is_loading === 0) {
    console.log("Bokeh: BokehJS loaded, going straight to plotting");
    run_inline_js();
  } else {
    load_libs(js_urls, function() {
      console.log("Bokeh: BokehJS plotting callback run at", now());
      run_inline_js();
    });
  }
}(window));
AUTOLOAD_NB_JS = <Template 'autoload_nb_js.js'>
Template: autoload_nb_js.js
{% extends "autoload_js.js" %}

{% block register_mimetype %}

  {%- if register_mime -%}
  var JS_MIME_TYPE = 'application/javascript';
  var HTML_MIME_TYPE = 'text/html';
  var EXEC_MIME_TYPE = 'application/vnd.bokehjs_exec.v0+json';
  var CLASS_NAME = 'output_bokeh rendered_html';

  /**
   * Render data to the DOM node
   */
  function render(props, node) {
    var script = document.createElement("script");
    node.appendChild(script);
  }

  /**
   * Handle when an output is cleared or removed
   */
  function handleClearOutput(event, handle) {
    var cell = handle.cell;

    var id = cell.output_area._bokeh_element_id;
    var server_id = cell.output_area._bokeh_server_id;
    // Clean up Bokeh references
    if (id !== undefined) {
      Bokeh.index[id].model.document.clear();
      delete Bokeh.index[id];
    }

    if (server_id !== undefined) {
      // Clean up Bokeh references
      var cmd = "from bokeh.io.state import curstate; print(curstate().uuid_to_server['" + server_id + "'].get_sessions()[0].document.roots[0]._id)";
      cell.notebook.kernel.execute(cmd, {
        iopub: {
          output: function(msg) {
            var element_id = msg.content.text.trim();
            Bokeh.index[element_id].model.document.clear();
            delete Bokeh.index[element_id];
          }
        }
      });
      // Destroy server and session
      var cmd = "import bokeh.io.notebook as ion; ion.destroy_server('" + server_id + "')";
      cell.notebook.kernel.execute(cmd);
    }
  }

  /**
   * Handle when a new output is added
   */
  function handleAddOutput(event, handle) {
    var output_area = handle.output_area;
    var output = handle.output;

    // limit handleAddOutput to display_data with EXEC_MIME_TYPE content only
    if ((output.output_type != "display_data") || (!output.data.hasOwnProperty(EXEC_MIME_TYPE))) {
      return
    }

    var toinsert = output_area.element.find("." + CLASS_NAME.split(' ')[0]);

    if (output.metadata[EXEC_MIME_TYPE]["id"] !== undefined) {
      toinsert[0].firstChild.textContent = output.data[JS_MIME_TYPE];
      // store reference to embed id on output_area
      output_area._bokeh_element_id = output.metadata[EXEC_MIME_TYPE]["id"];
    }
    if (output.metadata[EXEC_MIME_TYPE]["server_id"] !== undefined) {
      var bk_div = document.createElement("div");
      bk_div.innerHTML = output.data[HTML_MIME_TYPE];
      var script_attrs = bk_div.children[0].attributes;
      for (var i = 0; i < script_attrs.length; i++) {
        toinsert[0].firstChild.setAttribute(script_attrs[i].name, script_attrs[i].value);
      }
      // store reference to server id on output_area
      output_area._bokeh_server_id = output.metadata[EXEC_MIME_TYPE]["server_id"];
    }
  }

  function register_renderer(events, OutputArea) {

    function append_mime(data, metadata, element) {
      // create a DOM node to render to
      var toinsert = this.create_output_subarea(
        metadata,
        CLASS_NAME,
        EXEC_MIME_TYPE
      );
      this.keyboard_manager.register_events(toinsert);
      // Render to node
      var props = {data: data, metadata: metadata[EXEC_MIME_TYPE]};
      render(props, toinsert[0]);
      element.append(toinsert);
      return toinsert
    }

    /* Handle when an output is cleared or removed */
    events.on('clear_output.CodeCell', handleClearOutput);
    events.on('delete.Cell', handleClearOutput);

    /* Handle when a new output is added */
    events.on('output_added.OutputArea', handleAddOutput);

    /**
     * Register the mime type and append_mime function with output_area
     */
    OutputArea.prototype.register_mime_type(EXEC_MIME_TYPE, append_mime, {
      /* Is output safe? */
      safe: true,
      /* Index of renderer in `output_area.display_order` */
      index: 0
    });
  }

  // register the mime type if in Jupyter Notebook environment and previously unregistered
  if (root.Jupyter !== undefined) {
    var events = require('base/js/events');
    var OutputArea = require('notebook/js/outputarea').OutputArea;

    if (OutputArea.prototype.mime_types().indexOf(EXEC_MIME_TYPE) == -1) {
      register_renderer(events, OutputArea);
    }
  }
  {%- endif -%}

{% endblock %}

{% block autoload_init %}
  if (typeof (root._bokeh_timeout) === "undefined" || force === true) {
    root._bokeh_timeout = Date.now() + {{ timeout|default(0)|json }};
    root._bokeh_failed_load = false;
  }

  var NB_LOAD_WARNING = {'data': {'text/html':
     "<div style='background-color: #fdd'>\n"+
     "<p>\n"+
     "BokehJS does not appear to have successfully loaded. If loading BokehJS from CDN, this \n"+
     "may be due to a slow or bad network connection. Possible fixes:\n"+
     "</p>\n"+
     "<ul>\n"+
     "<li>re-rerun `output_notebook()` to attempt to load from CDN again, or</li>\n"+
     "<li>use INLINE resources instead, as so:</li>\n"+
     "</ul>\n"+
     "<code>\n"+
     "from bokeh.resources import INLINE\n"+
     "output_notebook(resources=INLINE)\n"+
     "</code>\n"+
     "</div>"}};

  function display_loaded() {
    var el = document.getElementById({{ elementid|json }});
    if (el != null) {
      el.textContent = "BokehJS is loading...";
    }
    if (root.Bokeh !== undefined) {
      if (el != null) {
        el.textContent = "BokehJS " + root.Bokeh.version + " successfully loaded.";
      }
    } else if (Date.now() < root._bokeh_timeout) {
      setTimeout(display_loaded, 100)
    }
  }
{% endblock %}

{% block run_inline_js %}
    if ((root.Bokeh !== undefined) || (force === true)) {
      for (var i = 0; i < inline_js.length; i++) {
        inline_js[i].call(root, root.Bokeh);
      }
      {%- if elementid -%}
      if (force === true) {
        display_loaded();
      }
      {%- endif -%}
    } else if (Date.now() < root._bokeh_timeout) {
      setTimeout(run_inline_js, 100);
    } else if (!root._bokeh_failed_load) {
      console.log("Bokeh: BokehJS failed to load within specified timeout.");
      root._bokeh_failed_load = true;
    } else if (force !== true) {
      var cell = $(document.getElementById({{ elementid|json }})).parents('.cell').data().cell;
      cell.output_area.append_execute_result(NB_LOAD_WARNING)
    }
{% endblock %}
AUTOLOAD_TAG = <Template 'autoload_tag.html'>

Renders <script> tags that automatically load BokehJS (if necessary) and then renders a Bokeh model or document. The document may be specified as either an embedded doc ID or a server session ID. If a specific model ID is not specified, the entire document will be rendered.

Parameters:
  • src_path (str) – path to AUTOLOAD script
  • elementid (str) – the a unique id for the script tag
  • modelid (str) – The Bokeh model id for the object to render (if missing, render the whole doc; if present, only render the one model)
  • docid (str) – The id of the embedded Bokeh document to render

Note

This script injects a <div> in place, so must be placed under <body>.

Template: autoload_tag.html
<script
    src="{{ src_path }}"
    id="{{ elementid }}"
    data-bokeh-model-id="{{ modelid }}"
    data-bokeh-doc-id="{{ docid }}"
></script>
CSS_RESOURCES = <Template 'css_resources.html'>

Renders HTML that loads Bokeh CSS according to the configuration in a Resources object.

Parameters:
  • css_files (list[str]) – a list of URIs for CSS files to include
  • css_raw (list[str]) – a list of raw CSS snippets to put between <style> tags
Template: css_resources.html
{%- for file in css_files %}
<link rel="stylesheet" href="{{ file }}" type="text/css" />
{%- endfor %}

{%- for css in css_raw %}
<style>
    {{ css|indent(8) }}
</style>
{%- endfor %}
DOC_JS = <Template 'doc_js.js'>
Template: doc_js.js
(function(root) {
  function embed_document(root) {
    var docs_json = {{ docs_json }};
    var render_items = {{ render_items }};
    root.Bokeh.embed.embed_items(docs_json, render_items{%- if app_path -%}, "{{ app_path }}" {%- endif -%}{%- if absolute_url -%}, "{{ absolute_url }}" {%- endif -%});
  }
  if (root.Bokeh !== undefined) {
    embed_document(root);
  } else {
    var attempts = 0;
    var timer = setInterval(function(root) {
      if (root.Bokeh !== undefined) {
        embed_document(root);
        clearInterval(timer);
      }
      attempts++;
      if (attempts > 100) {
        console.log("Bokeh: ERROR: Unable to embed document because BokehJS library is missing")
        clearInterval(timer);
      }
    }, 10, root)
  }
})(window);
FILE = <Template 'file.html'>

Renders Bokeh models into a basic .html file.

Parameters:
  • title (str) – value for <title> tags
  • plot_resources (str) – typically the output of RESOURCES
  • plot_script (str) – typically the output of PLOT_SCRIPT
  • plot_div (str) – typically the output of PLOT_DIV

Users can customize the file output by providing their own Jinja2 template that accepts these same parameters.

Template: file.html
<!DOCTYPE html>
<html lang="en">
    <head>
        <meta charset="utf-8">
        <title>{{ title|e if title else "Bokeh Plot" }}</title>
        {{ bokeh_css }}
        {{ bokeh_js }}
        <style>
          html {
            width: 100%;
            height: 100%;
          }
          body {
            width: 90%;
            height: 100%;
            margin: auto;
          }
        </style>
    </head>
    <body>
        {{ plot_div|indent(8) }}
        {{ plot_script|indent(8) }}
    </body>
</html>
JS_RESOURCES = <Template 'js_resources.html'>

Renders HTML that loads BokehJS JavaScript code and CSS according to the configuration in a Resources object.

Parameters:
  • js_files (list[str]) – a list of URIs for JS files to include
  • js_raw (list[str]) – a list of raw JS snippets to put between <style> tags
Template: js_resources.html
{%- for file in js_files %}
<script type="text/javascript" src="{{ file }}"></script>
{%- endfor %}

{%- for js in js_raw %}
<script type="text/javascript">
    {{ js|indent(8) }}
</script>
{%- endfor %}
NOTEBOOK_LOAD = <Template 'notebook_load.html'>

Renders HTML for loading BokehJS JavaScript code and CSS into a Jupyter Notebook according to a Resources object.

Parameters:
  • plot_resources (str) – typically the output of RESOURCES
  • verbose (bool) – whether to display verbose info about BokehJS configuration, etc
  • bokeh_version (str) – the current version of Bokeh
  • js_info (str) – information about the location, version, etc. of BokehJS code
  • css_info (str) – information about the location, version, etc. of BokehJS css
  • warnings (list[str]) – a list of warnings to display to user
Template: notebook_load.html
    <div class="bk-root">
        <a href="https://bokeh.pydata.org" target="_blank" class="bk-logo bk-logo-small bk-logo-notebook"></a>
        <span id="{{ element_id }}">Loading BokehJS ...</span>
    </div>
    {%- if verbose %}
    <style>
        p.bokeh_notebook { margin-left: 24px; }
        table.bokeh_notebook {
            border: 1px solid #e7e7e7;
            margin: 5px;
            margin-left: 24px;
            width: 80%;
        }
        tr.bokeh_notebook {
            border: 1px solid #e7e7e7;
            background-color: #FFF;
        }
        th.bokeh_notebook {
            border: 1px solid #e7e7e7;
            background-color: #f8f8f8;
            text-align: center;
        }
        td.bokeh_notebook {
            border: 1px solid #e7e7e7;
            background-color: #d2d7ec;
            text-align: left;
        }
    </style>
    <p class="bokeh_notebook">Using Settings:</p>
    <table class="bokeh_notebook">
        <tr class="bokeh_notebook">
            <th class="bokeh_notebook">Bokeh</th>
            <th class="bokeh_notebook">version</th>
            <td class="bokeh_notebook">{{ bokeh_version }}</td>
        </tr>
        <tr class="bokeh_notebook">
            <th class="bokeh_notebook" rowspan="2">BokehJS</th>
            <th class="bokeh_notebook">js</th>
            <td class="bokeh_notebook">{{ js_info }}</td>
        </tr>
        <tr class="bokeh_notebook">
            <th class="bokeh_notebook">css</th>
            <td class="bokeh_notebook">{{ css_info }}</td>
        </tr>
    </table>
    {%- endif %}
    {%- for warning in warnings %}
    <p style="background-color: #f2d7dc;">{{ warning }}</p>
    {%- endfor %}
PLOT_DIV = <Template 'plot_div.html'>

Renders a basic plot div, that can be used in conjunction with PLOT_JS.

Parameters:elementid (str) – a unique identifier for the <div> a PLOT_JS template should be configured with the same elementid
Template: plot_div.html
<div class="bk-root">
    <div class="bk-plotdiv" id="{{ elementid }}"></div>
</div>
SCRIPT_TAG = <Template 'script_tag.html'>

Renders a <script> tag for raw JavaScript code.

Parameters:js_code (str) – raw JavaScript code to put in the tag.
Template: script_tag.html
<script type="{{ type }}"{%if id %} id="{{ id }}"{% endif %}>
{{ js_code }}
</script>