reinfolib

Unofficial TypeScript client for Japan MLIT Real Estate Information Library API.

This package is not affiliated with, endorsed by, or sponsored by Japan MLIT. Users must comply with MLIT terms of use and obtain their own API key.

MLIT documents recommend not sending API requests directly from browsers because of CORS. Use this client from Node.js, server-side rendering, edge/server runtimes, or your own backend/proxy.

Install

pnpm add reinfolib

Quick start

import { createClient } from "reinfolib"

const client = createClient({
  apiKey: process.env.REINFOLIB_API_KEY!,
})

const municipalities = await client.xit002({ area: "13" })
// friendly alias for the same endpoint
const same = await client.getMunicipalities({ area: "13" })

Features

• Fully typed endpoint methods for every API listed in the public manual.
• Official ID methods (xit001) plus friendly aliases (getRealEstatePrices).
• ofetch internally, including $fetch.raw-style raw responses.
• Non-tile JSON methods unwrap MLIT { status: "OK", data } envelopes and return data directly.
• Valibot request validation before network calls.
• GeoJSON/PBF tile endpoints with conditional return types.
• Coordinate overloads for tile endpoints: pass either z/x/y or zoom/longitude/latitude.
• Public endpoint metadata, request schemas, prefecture constants, and URL builders.

Examples

Non-tile JSON endpoint

const prices = await client.xit001({
  year: 2024,
  quarter: 1,
  city: "13102",
  priceClassification: "01",
})

GeoJSON tile endpoint

const geojson = await client.xpt001({
  responseFormat: "geojson",
  z: 14,
  x: 14624,
  y: 6016,
  from: 20252,
  to: 20252,
})

Coordinate overload

const useDistricts = await client.getUseDistricts({
  responseFormat: "geojson",
  zoom: 14,
  longitude: 139.767,
  latitude: 35.681,
})

PBF tile endpoint

const pbf = await client.xkt001({
  responseFormat: "pbf",
  z: 14,
  x: 14626,
  y: 6020,
})
// ArrayBuffer

Raw response and URL builder

const response = await client.raw.xit002({ area: "13" })
// Raw methods keep the MLIT envelope on _data: { status: "OK", data: [...] }
console.log(response.status, response.headers, response._data)

const url = client.url.xit002({ area: "13" })
// No API key is included in generated URLs.

Configure ofetch

const client = createClient({
  apiKey: process.env.REINFOLIB_API_KEY!,
  timeout: 30_000,
  fetchOptions: {
    retry: false,
    onRequest({ request }) {
      console.debug("reinfolib", request)
    },
  },
})

Endpoint methods

| ID | Methods | API | Response | | --- | --- | --- | --- | | XIT001 | xit001 / getRealEstatePrices | 不動産価格（取引価格・成約価格）情報取得API | JSON | | XIT002 | xit002 / getMunicipalities | 都道府県内市区町村一覧取得API | JSON | | XCT001 | xct001 / getAppraisalReports | 鑑定評価書情報API | JSON | | XPT001 | xpt001 / getRealEstatePricePoints | 不動産価格（取引価格・成約価格）情報のポイント (点) API | GeoJSON/PBF tile | | XPT002 | xpt002 / getLandPricePoints | 地価公示・地価調査のポイント (点) API | GeoJSON/PBF tile | | XKT001 | xkt001 / getUrbanPlanningAreas | 都市計画決定GISデータ（都市計画区域/区域区分）API | GeoJSON/PBF tile | | XKT002 | xkt002 / getUseDistricts | 都市計画決定GISデータ（用途地域）API | GeoJSON/PBF tile | | XKT003 | xkt003 / getLocationNormalizationPlans | 都市計画決定GISデータ（立地適正化計画）API | GeoJSON/PBF tile | | XKT004 | xkt004 / getElementarySchoolDistricts | 国土数値情報（小学校区）API | GeoJSON/PBF tile | | XKT005 | xkt005 / getJuniorHighSchoolDistricts | 国土数値情報（中学校区）API | GeoJSON/PBF tile | | XKT006 | xkt006 / getSchools | 国土数値情報（学校）API | GeoJSON/PBF tile | | XKT007 | xkt007 / getPreschools | 国土数値情報（保育園・幼稚園等）API | GeoJSON/PBF tile | | XKT010 | xkt010 / getMedicalFacilities | 国土数値情報（医療機関）API | GeoJSON/PBF tile | | XKT011 | xkt011 / getWelfareFacilities | 国土数値情報（福祉施設）API | GeoJSON/PBF tile | | XKT013 | xkt013 / getFuturePopulationMeshes | 国土数値情報（将来推計人口250mメッシュ）API | GeoJSON/PBF tile | | XKT014 | xkt014 / getFirePreventionDistricts | 都市計画決定GISデータ（防火・準防火地域）API | GeoJSON/PBF tile | | XKT015 | xkt015 / getStationPassengerCounts | 国土数値情報（駅別乗降客数）API | GeoJSON/PBF tile | | XKT016 | xkt016 / getDisasterRiskAreas | 国土数値情報（災害危険区域）API | GeoJSON/PBF tile | | XKT017 | xkt017 / getLibraries | 国土数値情報（図書館）API | GeoJSON/PBF tile | | XKT018 | xkt018 / getMunicipalOffices | 国土数値情報（市区町村役場及び集会施設等）API | GeoJSON/PBF tile | | XKT019 | xkt019 / getNaturalParks | 国土数値情報（自然公園地域）API | GeoJSON/PBF tile | | XKT020 | xkt020 / getLargeScaleEmbankments | 国土数値情報（大規模盛土造成地マップ）API | GeoJSON/PBF tile | | XKT021 | xkt021 / getLandslidePreventionAreas | 国土数値情報（地すべり防止地区）API | GeoJSON/PBF tile | | XKT022 | xkt022 / getSteepSlopeHazardAreas | 国土数値情報（急傾斜地崩壊危険区域）API | GeoJSON/PBF tile | | XKT023 | xkt023 / getDistrictPlans | 都市計画決定GISデータ（地区計画）API | GeoJSON/PBF tile | | XKT024 | xkt024 / getHighIntensityUseDistricts | 都市計画決定GISデータ（高度利用地区）API | GeoJSON/PBF tile | | XKT025 | xkt025 / getLiquefactionTendencyAreas | 国土交通省都市局（地形区分に基づく液状化の発生傾向図）API | GeoJSON/PBF tile | | XKT026 | xkt026 / getFloodInundationAreas | 国土数値情報（洪水浸水想定区域（想定最大規模））API | GeoJSON/PBF tile | | XKT027 | xkt027 / getStormSurgeInundationAreas | 国土数値情報（高潮浸水想定区域）API | GeoJSON/PBF tile | | XKT028 | xkt028 / getTsunamiInundationAreas | 国土数値情報（津波浸水想定）API | GeoJSON/PBF tile | | XKT029 | xkt029 / getSedimentDisasterHazardAreas | 国土数値情報（土砂災害警戒区域）API | GeoJSON/PBF tile | | XKT030 | xkt030 / getUrbanPlanningRoads | 都市計画決定GISデータ（都市計画道路）API | GeoJSON/PBF tile | | XKT031 | xkt031 / getDenselyInhabitedDistricts | 国土数値情報（人口集中地区）API | GeoJSON/PBF tile | | XGT001 | xgt001 / getEmergencyEvacuationSites | 国土地理院GISデータ（指定緊急避難場所）API | GeoJSON/PBF tile | | XST001 | xst001 / getDisasterHistory | 国土調査（災害履歴）API | GeoJSON/PBF tile |

Validation and errors

Request parameters are validated with Valibot. Validation failures throw ReinfolibValidationError with an issues array. Non-2xx HTTP and parsing failures follow ofetch behavior internally and are wrapped as ReinfolibApiError with status, statusText, url, endpoint, and responseText when available.

Response validation is intentionally not included in v1.

Live sampling fixtures

Tests use mocks by default. To fetch a small, rate-limit-conscious live fixture manually:

REINFOLIB_API_KEY=... pnpm sample

The script skips when REINFOLIB_API_KEY is not set and writes sanitized output under tests/fixtures/ when run.

CI and publishing

This repository includes GitHub Actions workflows:

• .github/workflows/ci.yml runs install, typecheck, tests, build, and a pnpm publish --dry-run package check.
• .github/workflows/publish.yml publishes tag pushes to npm with GitHub OIDC trusted publishing and provenance.

Create a changelog, bump package.json, commit, tag, and create a GitHub release with changelogen:

pnpm release

Then push the generated commit and tag:

git push --follow-tags

Before the first release, configure npm trusted publishing for this package and workflow in npm, or with npm CLI:

npm trust github reinfolib --file .github/workflows/publish.yml --allow-publish

Publishing happens when a v* tag is pushed, or manually through the Publish workflow. No NPM_TOKEN secret is required for trusted publishing.

License

MIT