Architecture
Mid Tier architecture for Progressive Web Application
Mid Tier is capable of rendering a progressive web application (PWA) for a custom application. The following image represents the architecture of Mid Tier that involves a cross-launch from Smart IT.
As part of the architecture, the Mid Tier backend is used to leverage its generic and AR System metadata-driven implementation, and the client-side rendering logic is changed to produce a user interface and experience that is similar to that of Smart IT.
The core business logic and functional logic, including Role Based Access Control (RBAC), exists in the BMC Helix ITSM application workflows. The ITSM data model also exists in the AR System with the business logic in filters. Smart IT and Mid Tier continue to work until the Progressive Web Application (PWA) technology completely replaces their functionality.
Instructions for classic interfaces
View instructions for classic Smart IT
PWA screens available from Smart IT
End users can open the following PWA screens from Smart IT:
- Incident
- Work Order
- Problem Investigation
- Task
- Known Error
- Asset
- People
- Broadcast
- Change
The following video shows some of the PWA screens in Smart IT
You can enable opening of these PWA screens from Smart IT by using the cross-launch settings configured in the Centralized Configuration. The following diagram illustrates how PWA screens are viewed from Smart IT:
When a screen is available in PWA, Mid Tier screens are displayed from Smart IT as described in the following steps, which illustrate the example of when a Smart IT user views an incident ticket.
- The Incident screen is available as PWA, so Mid Tier is cross-launched from Smart IT so that the incident ticket can be viewed as PWA.
- The Incident screen is available as PWA, so the user is redirected to Mid Tier. The user views the incident and gets the incident details such as tasks and notes.
- Mid Tier sends the final response to the Smart IT user.
The following list shows the information flow when a Smart IT user accesses a screen that is available only in Smart IT:
A. The request to view a screen is sent to the Smart IT server because the interface is not available as PWA.
B. An authentication REST API call is sent to the Smart IT server.
C. A user logs in to BMC Helix ITSM.
D. BMC Helix ITSM displays the information to the user.
View instructions for Mid Tier
A database forms the underlying element of the BMC Helix ITSM architecture. The AR System is on top of the database. AR System processes all data entered by BMC Helix ITSM applications. In addition, the AR System is the workflow engine between the BMC Helix ITSM applications and the database. It also verifies that a user has permission to perform each action, thereby enforcing any access control defined in the applications.
In this capacity, the AR System is the interface between the database and the BMC Helix CMDB, which includes the Product Catalog and BMC Helix CMDB. CMDB stores information about the configuration items (CIs) in your IT environment and the relationships between them. BMC Atrium CMDB makes this information available to the BMC Helix ITSM applications and their various shared application components, such as the Task Management.
The AR System also manages the following:
- The Approval Server is a self-contained, shared module that enables you to automate any approval or signature process. For more information about Approval Server, see Automatic request assignment.
- The Assignment Engine enables you to automatically assign requests to individuals. For more information about Assignment Engine, see Automatic request assignment.
The relationships among the database, AR System, CMDB, shared application components, and the BMC Helix ITSM applications are shown in the following illustration.
For a detailed overview of the BMC Helix ITSM (BMC Helix ITSM) architecture, see Mid Tier architecture.