Implement Versioned Document Types

[adjdred]

📌 Summary

Implement a versioned DocumentType system to support multi-tenant document templates (e.g. certificates, transcripts, HEARs). Each document type can have multiple versions that apply from a specified time onward. Documents must reference the correct version based on their IssuedTime.

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🧱 Entity: DocumentType

A single table that supports both grouping and versioning via a ParentId.

Fields:

• Id: Unique identifier
• TenantId: Multi-tenancy support
• ParentId: Reference to the root version (null if this is the first version)
• Name: Friendly name of the template version (e.g. "Transcript v2")
• TypeName: Category (e.g. Certificate, Transcript, Letter)
• Version: Version string or number
• ValidFromTime: The time this version becomes active
• IsActive: Indicates if the version is enabled for use
• CreationTime: Timestamp (via ABP ICreationAudited)

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📄 Requirements

• Create DocumentType entity using FullAuditedAggregateRoot<Guid> and IMultiTenant
• Support self-referencing ParentId to model versions under a shared logical group
• Ensure DocumentTypeField and other related data link to the correct version
• Add ability to resolve the correct DocumentType for a document using IssuedTime
• Enforce uniqueness of (TenantId, ParentId, Version) if applicable
• Seed or create the first version with ParentId = null
• Add methods in the domain/application layer to:
  • Create a new version
  • Retrieve current version for a group
  • Get all versions by root ID

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📦 Example: Document Version Resolution Logic

var applicableVersion = dbContext.DocumentTypes
    .Where(dt => dt.ParentId == rootId || dt.Id == rootId)
    .Where(dt => dt.ValidFromTime <= document.IssuedTime)
    .OrderByDescending(dt => dt.ValidFromTime)
    .FirstOrDefault();