[INJICERT-863] Openapi review comments

README.md

@@ -36,6 +36,9 @@ public interface DataProviderPlugin {
 
 Refer to [SQL scripts](db_scripts) and go through it's README
 
+## Rendering Template
+Refer to [Rendering Template](docs/Rendering-Template.md)
+
 # Local Installation Guide (via Docker Compose)
 
 The following steps will help you to setup Sunbird RC and Esignet services using Docker compose alongwith Certify.

docs/Rendering-Template.md

@@ -0,0 +1,77 @@
+# Rendering Template Integration for Inji Certify (OpenID4VCI 2.0 RenderMethod)
+
+This document explains the integration of Credential rendering templates in Inji Certify using [VC Render Specification](https://w3c-ccg.github.io/vc-render-method/).
+
+1. To use the Verifiable Credential Data Model 2.0 optional features one can configure them in the Velocity Template present in [this file](./certify_init.sql)as per [this draft spec](https://w3c-ccg.github.io/vc-render-method/). The Render Template has to be routable by all the clients and should be cached appropriately. The template is not expected to be updated as the consuming clients are expected to verify the integrity with the provided `digestMultibase`. For detailed information please go through the draft spec.
+
+```json
+  "renderMethod": [{
+    "id": "https://yourdomain.certify.io/v1/certify/rendering-template/national-id",
+    "type": "SvgRenderingTemplate",
+    "name": "Portrait Mode",
+    "css3MediaQuery": "@media (orientation: portrait)",
+    "digestMultibase": "zQmAPdhyxzznFCwYxAp2dRerWC85Wg6wFl9G270iEu5h6JqW"
+  }]
+```
+
+```mermaid
+sequenceDiagram
+    participant User as 👤 User
+    participant MobileWallet as 📱 Mobile Wallet
+    participant Admin as 👤 Admin
+
+    box "Inji Certify" #LightBlue
+        participant CredentialIssuer as 📜 Credential Issuer
+        participant RenderingService as 🔧 Rendering Service
+        participant Config as ⚙️ application.properties
+        participant TemplateStore as 🗄️ Template Store
+    end
+
+    %% Setup Phase
+    Note over User,TemplateStore: ==================== Setup Phase ====================
+    Admin->>TemplateStore: Add New Template using sql queris
+    TemplateStore-->>Admin: Template ID
+
+    Note over Config: SVG Rendering Template Template Configuration
+    Admin->>Config: Configure mosip.certify.data-provider-plugin.rendering-template-id
+    Config->>RenderingService: Load template mappings
+
+    %% Divider between setup and credential flow
+    Note over User,TemplateStore: ==================== Credential Flow ====================
+
+    User ->> MobileWallet: Request Credential
+    MobileWallet->>CredentialIssuer: Request Credential
+    CredentialIssuer->>MobileWallet: Issue VC (openid4vci) (v2.0 Data Model)
+
+    MobileWallet->>RenderingService: GET Rendering Template
+    RenderingService ->> TemplateStore: Get Rendering Template
+    TemplateStore ->> RenderingService: Template
+    RenderingService ->> MobileWallet: Template
+    Note left of RenderingService: Set Headers:<br/>- Content-Type: image/svg+xml<br/>- Cache-Control: max-age=604800<br/>- Vary: Accept-Language
+    MobileWallet->>MobileWallet: Render SVG<br/>(Interactive Display)
+```
+
+### 🔄 Credential Flow
+
+1. **User Initiation**: Request credential via Mobile Wallet
+
+2. **VC Issuance**:
+   - Wallet → Credential Issuer: /credential request
+   - Response: Signed VC with renderMethod claim
+
+3. **Template Fetch**:
+```http
+GET /rendering-template/vaccine_card_v1
+```
+
+4. **SVG Rendering**:
+   - Wallet processes SVG with VC data binding
+
+## 🖋️ Response Headers
+
+| Header | Value | Purpose |
+|--------|-------|---------|
+| Content-Type | image/svg+xml | MIME type enforcement |
+| Cache-Control | max-age=604800 | CDN/browser caching |
+
+The digest multibase can be hardcoded or if the template has been stored with Certify's DB & `mosip.certify.data-provider-plugin.rendering-template-id` is set to the correct the value `${_renderMethodSVGdigest}` can be used to enable Certify to evaluate it specifying the id of the rendering-template used. However, for optimal performance, it's recommended to not set this key and instead hardcode the `digestMultibase` value in the Velocity template itself.