klod68/gen-service-interface

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name: gen-service-interface description: "Use when defining the public contract for a new domain service or application service. Generates a CQS-categorized interface with Commands, Queries, Validators, a Criteria class, and XML doc comments. Also invoke when the user mentions: service interface, IMyService, define service contract, add service interface, application service interface. Domain: Code Generation, Architecture. Level: Intermediate."

Generate a CQS-categorized service interface for the entity: ${1:EntityName}.

Context

• Key type: ${2|int,Guid,string|}
• Namespace root: ${3:MyApp}
• Create parameters: ${4:string name, string description}
• Update parameters: ${5:int id, string name, string description}
• Filterable properties: ${6:string? nameSearch, string? category}

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Required output — generate ALL of the following:

1. Service interface

${3}.Domain.Services.I${1}Service.cs

Divide methods into three #region blocks:

Commands — side-effect operations, return technical receipts only:

• InsertAsync(${4}, CancellationToken ct = default) → Task<${2}>
• UpdateAsync(${5}, CancellationToken ct = default) → Task<bool>
• DeleteAsync(${2} id, CancellationToken ct = default) → Task<bool>

Queries — pure reads, no side effects:

• GetByIdAsync(${2} id, CancellationToken ct = default) → Task<${1}?>
• GetByCriteriaAsync(${1}Criteria criteria, CancellationToken ct = default) → Task<IReadOnlyList<${1}>>
• GetPagedAsync(${1}Criteria criteria, IPagedRequest paging, CancellationToken ct = default) → Task<IPagedResult<${1}>>

Validators — boolean checks, no side effects:

• ExistsAsync(${2} id, CancellationToken ct = default) → Task<bool>

2. Criteria record

${3}.Domain.Services.${1}Criteria.cs

• Sealed record, all properties nullable (null = don't filter)
• One property per filterable field listed above
• XML doc on the record and each property

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Rules

• All async methods include CancellationToken cancellationToken = default
• Collection returns use IReadOnlyList<T> — never List<T> or IEnumerable<T>
• Commands return technical receipts only (new ID, affected-row count, or bool) — never domain objects
• Queries are referentially transparent — calling them twice in a row produces the same result
• Validators always return bool / Task<bool> — no other return type
• XML documentation on the interface, every method, and every parameter
• Method naming follows CQS:
  • Commands: Insert, Update, Delete, Execute
  • Queries: Get, Find, Load
  • Validators: Exists, Is, Has, Can

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Constraints

• Follow all rules in the workspace root instruction file
• The interface is public — it is a domain contract
• No concrete types in parameters or return types
• No EF, infrastructure, or framework references in the Domain layer