.. _Types of Dynamic Applications: https://docs.sciencelogic.com/latest/Content/Web_Content_Dev_and_Integration/Dynamic_Application_Development/dynamic_app_dev_intro.htm


####################################
Additional |FRAMEWORK_NAME| Features
####################################

The |FRAMEWORK_NAME| also has other features that will help you to define your
Dynamic Applications.

.. _substitution:


************
Substitution
************

Substitution occurs during the Argument Parsing |STEP_NAME|, prior to
converting the snippet argument into the appropriate |STEP_NAME_PLURAL|
for the framework to execute. Substitution occurs for the following values,
indicated within the ``<`` and ``>`` characters.

.. list-table::

    * - <silo:app_id>
      - The application ID of the Dynamic Application
    * - <silo:gmtime>
      - The timestamp for the data when saving to the database
        for the Dynamic Application
    * - <silo:freq>
      - The poll frequency of the Dynamic Application
    * - <silo:comp_name>
      - The name of this component device
    * - <silo:comp_dn>
      - The Unique identifier for the DCM tree of this component device
    * - <silo:comp_uid>
      - The Unique ID of this component device
    * - <silo:did>
      - The Device ID (DID) of this device/component device
    * - <silo:root_did>
      - The root Device ID of this component device
    * - <silo:parent_did>
      - The parent Device ID of this component device
    * - <silo:guid>
      - The Globally Unique Identifier (GUID) of this component device
    * - <silo:ip>
      - The IP address of this component device

Substitution Usage
==================

The way to use the substitution values is as follows:

.. image:: _static/snippet_arg_substitution.png

Custom Substitution
===================

You can also write your custom substitution in the snippet code. An empty
dictionary, called ``custom_substitution``, lets you build your own
custom substitutions.

The example below shows you how to do custom substitutions:

.. image:: _static/custom_substitution.png

Substitution Example
====================

Suppose we have a device with a Unique Identifier equal to ``/api/account/1``
and a custom substitution as in the avobe image.
The substitution in the snippet argument will be as follows.

+-------------------------------------+-------------------------------------+
| Before substitution                 | After substitution                  |
+-------------------------------------+-------------------------------------+
| .. code-block:: none                | .. code-block:: none                |
|    :emphasize-lines: 5,8            |    :emphasize-lines: 5,8            |
|                                     |                                     |
|    low_code:                        |    low_code:                        |
|      version: 2.0                   |      version: 2.0                   |
|      id: FirstName                  |      id: FirstName                  |
|      steps:                         |      steps:                         |
|        - http:                      |        - http:                      |
|          uri: "<silo:comp_uid>"     |          uri: "/api/account/1"      |
|        - json                       |        - json                       |
|        - simple_key: "<data_key>"   |        - simple_key: "contact_fname"|
+-------------------------------------+-------------------------------------+


************
Bulk Snippet
************

Bulk Snippets are designed to improve performance when the same network
request can service many collections. This means that if you need substitution
during a Requestor, there is limited or no benefit to Bulk Snippets.
On the other hand, if your substitution is happening during a processor,
Bulk Snippets will reduce the number of network requests and improve
overall performance. As an example you would want to use a bulk snippet if you
are using a component UID when selecting the result using the jsonpath
|STEP_NAME|.

.. note::

  The |FRAMEWORK_NAME| will execute bulk collection if the application type
  is configured to Bulk Snippet.