Notion

Local emulators. Real API contracts. Part of Mockingbird.

WIP Notion 2022-06-28 database search, OAuth token exchange, database-parent page creation and block-children reads. This is the legacy database API, not the newer data-source API.

#Install

bun add @crvouga/mockingbird-service-notion

#Usage

import { Client } from "@notionhq/client"
import { createRuntime } from "@crvouga/mockingbird-service-notion"

// The app's own Notion client. Only its fetch changes: requests reach the
// emulator in this process instead of api.notion.com.
const emulator = createRuntime()
const notion = new Client({
  auth: "mock_notion_token",
  notionVersion: "2022-06-28",
  fetch: (url: string, init?: RequestInit) => emulator.fetch(new Request(url, init)),
})
const { results } = await notion.search({ filter: { property: "object", value: "database" }, page_size: 100 })
const [database] = results
if (database?.object === "database") console.log(database.properties)

The example uses @notionhq/client@2.2.15, the SDK line for this API version. Run mockingbird-notion serve --port 12127 and inject http://localhost:12127 as the consumer's API origin (the SDK's baseUrl). Keep /v1 in raw request paths. No universal vendor environment variable exists for this origin override. The reported integration uses raw fetch.

#Contract

• POST /v1/oauth/token: HTTP Basic client credentials and a JSON authorization-code grant. Constructor/admin-seeded codes bind a client, redirect URI and workspace grant. Codes are single-use; successful exchange returns token, bot and workspace metadata.
• POST /v1/search: Bearer grant plus Notion-Version: 2022-06-28. Returns legacy page_or_database lists with database ids/properties, query filtering, page_size, start_cursor, next_cursor and has_more. Results are limited to the granted workspace and database ids. Fixture insertion order is stable; relevance ranking is not modelled.
• POST /v1/pages: database_id parent and properties addressed by name or id. Successful writes return 200 with a page UUID and retain the parent/properties. Unknown or inaccessible parents return 404; read-only grants return 403. Unknown properties and wrong value types return 400 without partial writes.
• GET /v1/blocks/{block_id}/children: the read that returns a page's content (a page id is also a block id; hyphenated or 32-hex ids resolve to the same page). Returns the documented {object: "list", results, next_cursor, has_more, type: "block", block: {}} with blocks in seeded order; each block carries id, type, has_children, parent and a <type> object (rich_text[].plain_text, to_do.checked, code.language / code.caption[].plain_text). A block with has_children: true lists its nested blocks from its own id, to any depth. page_size defaults to and is capped at 100. Block shapes are docs-verified (https://developers.notion.com/reference/get-block-children), not oracle-verified. Best guess, not oracle-verified: the opaque next_cursor (the last returned block's id; an unknown start_cursor is 400 validation_error), the exact error messages, 404 object_not_found for an unknown id or a page outside the grant, 400 validation_error for a non-UUID id, and 401 unauthorized for a missing or unknown token. The 429 and 5xx cases use the shared presets.

The default fixture is one synthetic survey database (Name/title, Score/number) with mock_notion_token. Configure databases, grants, clients and codes for other workspaces and OAuth scenarios. No authorization browser or webhooks are required by this subset.

#Controls

PUT /__admin/pages/{id}/blocks seeds a page's block tree from a nested outline, e.g. {"blocks": [{"type": "heading_1", "text": "FAQ"}, {"type": "toggle", "text": "Q", "children": [{"type": "code", "text": "x", "language": "bash", "caption": "c"}]}], "workspaceId"?, "title"?}. Types: paragraph, heading_1..3, bulleted_list_item, numbered_list_item, to_do (checked), toggle, quote, callout, code (language, caption), divider. The emulator expands the outline into Notion's block shape and replaces any earlier tree for that page; an unknown id becomes a standalone page. The whole outline is validated first: a problem is 400 and nothing is stored. Block writes through the API (PATCH, update, delete) are not modelled.

Shared /__admin/state/{databases,grants,clients,codes,pages} surfaces seed and inspect records. Reset restores constructor fixtures and clears created pages. Shared Timeline, clock, journal and fault APIs apply; logs do not contain page contents or credentials. Use only synthetic data. Namespaces are selected by header, /__admin/ns/{name} prefix or mapped bearer tokens. Set adminPrefix to relocate controls.

Presets: unauthorized, rate_limited (429, Retry-After), server_error (503) and connection_drop. Shared fault rules support latency and one-shot failures.

Acceptance tests cover issue #284 through raw fetch, OAuth binding/replay, schema errors, pagination, isolation/reset, journal redaction and served HTTP. Property tests exercise all three operations and detect divergence. bun scripts/parity.ts requires NOTION_API_KEY; it only checks a pinned-version empty search, never creating real pages. Live parity has not run. The official SDK v2.2.15 types provide the archived wire-contract evidence.

#Deliberately not modelled

New data-source APIs, full rich-text rendering/mentions, block writes (reads and admin seeding exist), block types beyond the list above, database editing/querying, page-parent creation, relevance sorting, full page/database response metadata, formulas, rollups, select-option creation, relationship resolution and full vendor field constraints. Property validation checks the requested schema's value kind: title/text, number, checkbox, nullable strings/dates, select/status/multi-select, people/relation ids and file objects. It does not emulate every Notion property limit or expand typed request values to full response objects. Only the pinned API version is accepted.

#API

• NotionAPI: FetchAPI with fetch, reset and database/grant/client/code/page collections.
• createRuntime: shared admin, namespace, clock, faults and journal contract.
• NOTION_NAMESPACE: service name.
• NOTION_PRESETS: deterministic fault presets.
• DEFAULT_DATABASES: synthetic survey schema.
• BLOCK_TYPES: the block types the admin block outline accepts.
• document, operationIds, supportedOperationIds: generated OpenAPI metadata.
• createServer, serveTarget, DEFAULT_PORT from ./server: Node HTTP/CLI target (default port 12127).

Public types: Property, Database, Grant, OAuthCode, Client, Page, NotionAPIOptions, OperationId, SupportedOperationId.