pd_options: List of key-value pairs that define transient states for the kernel request, according to the following format: pd_options=”key1=value1;key2=value2;...”. When used in combination with the pd_entity attribute, the pd_options attribute invokes the PixieDust display() API. In this case, you can get the values from the metadata of a separate Notebook cell in which you have used the display() API. When using pd_options in display() mode, it is recommended for convenience, to use the JSON notation of pd_options by creating a child element called <pd_options> and include the JSON values as text.

Example with pd_options as child element invoking display():

<div pd_entity>
    <pd_options>
        {
            “mapboxtoken”: “XXXXX”,
            “chartsize”: “90”,
            “aggregation”: “SUM”,
            “rowCount”: “500”,
            “handlerId”: “mapView”,
            “rendererId”: “mapbox”,
            “valueFields”: “IncidntNum”,
            “keyFields”: “X,Y”,
            “basemap”: “light-v9”
        }
    </pd_options>
</div>

Example with pd_options as HTML attribute:

<!-- Invoke a route that displays a chart -->
<button type=”submit” pd_options=”showChart=true” pd_target=”chart{{prefix}}”>
    Show Chart
</button>

pd_entity: Used only to invoke the display() API on specific data. Must be used in combination with pd_options where key-value pairs will be used as arguments to display(). If no value is specified for the pd_entity attribute, then it is assumed to be the entity passed to the run method that starts the PixieApp. The pd_entity value can be either a variable defined in the Notebook or a field of the PixieApp (for example, pd_entity=”df”), or a field to an object using the dot notation (for example, pd_entity=”obj_instance.df”).

pd_target: By default, the output of a kernel request is injected in the overall output cell or dialog (if you use runInDialog=”true” as an argument to the run method). However, you can use pd_target=”elementId” to specify a target element that will receive the output. (Note that the elementId must exist in the current view.)

Example:

<div id=”chart{{prefix}}”>
<button type=”submit” pd_options=”showChart=true” pd_target=”chart{{prefix}}”>
    Show Chart
</button>
</div>

pd_script: This invokes arbitrary Python code as part of the kernel request. This can be used in combination with other attributes like pd_entity and pd_options. It’s important to note that the Python indentation rules (https://docs.python.org/2.0/ref/indentation.html) must be respected to avoid a runtime error.

If the Python code contains multiple lines, it is recommended to use pd_script as a child element and store the code as text.

Example:

<!-- Invoke a method to load a dataframe before visualizing it -->
<div id=”chart{{prefix}}”>
<button type=”submit”
    pd_entity=”df”
    pd_script=”self.df = self.load_df()”
    pd_options=”handlerId=dataframe”
    pd_target=”chart{{prefix}}”>
    Show Chart
</button>
</div>

pd_app: This dynamically invokes a separate PixieApp by its fully qualified class name. The pd_options attribute can be used to pass route arguments to invoke a specific route of the PixieApp.

Example:

<div pd_render_onload
     pd_option=”show_route_X=true”
     pd_app=”some.package.RemoteApp”>
</div>

pd_render_onload: This should be used to trigger a kernel request upon loading, as opposed to when a user clicks on an element or when a change event occurs. The pd_render_onload attribute can be combined with any other attribute that defines the request, like pd_options or pd_script. Note that this attribute should only be used with a div element.

Example:

<div pd_render_onload>
    <pd_script>
print(‘hello world rendered on load’)
    </pd_script>
</div>

pd_refresh: This is used to force the HTML element to execute a kernel request even if no event (click or change event) has occurred. If no value is specified, then the current element is refreshed, otherwise, the element with the ID specified in the value will be refreshed.

Example:

<!-- Update state before refreshing a chart -->
<button type=”submit”
    pd_script=”self.show_line_chart()”
    pd_refresh=”chart{{prefix}}”>
    Show line chart
</button>

pd_event_payload: This emits a PixieApp event with the specified payload content. This attribute follows the same rules as pd_options:

Example:

pd_event_handler: Subscribers can listen to an event by declaring a <pd_event_handler> child element which can accept any of the PixieApp kernel execution attributes like pd_options and pd_script. This element must use the pd_source attribute to filter which events they want to process. The pd_source attribute can contain one of the following values:

Example:

pd_refresh_rate: This is used to repeat the execution of an element at a specified interval expressed in milliseconds. This is useful for when you want to poll the state of a particular variable and show the result in the UI.

Example:

<div pd_refresh_rate=”3000”
    pd_script=”print(self.get_status())”>
</div>