@happyvertical/smrt-mobile-contract

Codegen for the s-m-r-t mobile foundation: projects a s-m-r-t manifest.json through a mobile allowlist into typed Kotlin (@Serializable DTOs for the KMP module) and Swift (plain structs) — plus the generated framework contract files checked into @happyvertical/smrt-mobile.

Design: ADR 0001; epic happyvertical/smrt#1745. Agent/developer guidance: AGENTS.md. Zero runtime dependencies by design — it reads manifest.json files directly and stays out of the smrt package DAG.

Install

pnpm add -D @happyvertical/smrt-mobile-contract

Usage — per-app domain DTOs

import {
  buildMobileContract,
  generateKotlinDtoFiles,
  generateSwiftDtoFile,
  writeFileSet,
} from '@happyvertical/smrt-mobile-contract';
import { readFileSync, writeFileSync } from 'node:fs';

const manifest = JSON.parse(
  readFileSync('packages/my-objects/src/manifest/manifest.json', 'utf8'),
);

const contract = buildMobileContract({
  manifests: [manifest],                     // one or more SMRT manifests
  allowlist: ['FieldReport', 'Attachment'],  // short or qualified names
  kotlinPackage: 'com.example.mobile.generated',
  sourceLabel: 'packages/my-objects/src/manifest/manifest.json',
});

writeFileSet(
  'apps/mobile/shared/src/commonMain/kotlin/generated',
  generateKotlinDtoFiles(contract),
);
writeFileSync(
  'apps/mobile/iosApp/App/GeneratedMobileDtos.swift',
  generateSwiftDtoFile(contract),
);

Allowlist rules

• Entries may be short names (FieldReport) or qualified names (@scope/pkg:FieldReport). A short name that matches objects in more than one manifest is an error — use the qualified name.
• Two allowlisted objects may not share a short name: generated <Name>Dto files would overwrite each other, so the build throws instead.
• Relationship declarations (oneToMany/manyToMany/hasMany) are excluded from DTO projection — they are not scalar columns.

Type mapping

Manifest type	Kotlin	Swift
text / status / foreignKey / crossPackageRef	String	String
integer	Long (64-bit — byte sizes/epochs overflow Int)	Int64
decimal	DecimalString? (string-encoded, no float precision loss)	String?
boolean	Boolean	Bool
datetime	Instant?	String?
json	JsonObject	String (raw JSON)

Field defaults come from default (current manifests) with defaultValue (amaru-era) as a fallback; every generated Kotlin field default-initializes for safe partial deserialization. Field names stay manifest-faithful (wire-format names, including created_at); keyword collisions are backtick-escaped per language. sourceHash (sha256 over allowlist + projected objects) is stamped into all output so drift is detectable.

Usage — the framework contract

The stable framework contract (support types, pack localization, and the /api/mobile auth/session/device DTOs) is emitted by this package and checked into smrt-mobile's contract/ directory. This package's build byte-verifies those files; regenerate after editing src/emit-framework.ts:

pnpm --filter @happyvertical/smrt-mobile-contract generate:framework

The Swift mirror (frameworkSwiftFiles()) is emitted on demand for SwiftUI apps; a parity test keeps it field-for-field in sync with the Kotlin side.

Development

pnpm build   # vite build + framework contract freshness verify
pnpm test    # vitest (goldens, mapping rules, parity, file-set round-trip)