Here we describe the Templates: here lives the customizable and re-usable business logic of Credential Issuance and verification

Intro

• What is a template?

  IMPORTANT

  Templates contain (re-usable) business logic for issuance and verification flow. Templates are scripted in Zencode executed by Zenroom and Slangroom, check the 🏗️ Core Technologies to know more.

• Where and how do I use a template?

  Templates are used in issuance Flows and Verification Flows. When editing a flow, you can select the desired template from a dropdown.

• How do edit a template? Inside the Template editor, in the DIDroom Dashboard. If you want to test the code, you may want to use the Slangroom editor or Apiroom.

• Where are templates executed? Depending if it's an Authorization, Issuance or Verification, the templates are executed inside a Microservice, inside the Wallet or inside the Verifier App [more about this later].

Authorization, Issuance and Verification Templates

There are 3 types of Template, they are visible in Organization > Home and in the Templates section.

Templates in Organization > Home

Templates section

Parameters and presets

Based on the type, each Template has a different set of Parameters. Templates are typically built from Presets.

Form structure

It define here the Parameters that Flow (using this Template) will receive as input, specifically,

-> Authorization Template: the parameters in the form will be input by the user in the Wallet app and processed by the Authorization Server.

-> Issuance Template: this time the parameters in the form will be passed by the Authorization Server and processed by the Credential Issuer.

-> Verification Template: the parameters in the form will be read inside the Verifiable Presentation produced by the Wallet App and processed by the Verifier App.

Custom Code

This contains the core logic of the Template. The Custom code can:

• Read and process the input coming from the parameters in the "Form structure"
• Read and process parameters in the "Zencode data"
• Create and process data on the fly
• Return the processed data: some types of Template, have a certain return data format (e.g. Authorization Template must return a JSON object named "data") but each template can send the output to a REST API or write it into a Database. The parameters relevant to REST APIs and Parameters must be loaded from "Zencode data" (see Presets for examples).

Template Editor

Toolchain

Templates are programmed in Zencode and Slangroom and can be tested in the Slangroom Editor, see: https://dyne.org/slangroom/

Slangroom Editor