Files
excalidraw-box/src/server/db.ts
2026-06-01 21:34:05 +00:00

488 lines
12 KiB
TypeScript

import { Database } from "bun:sqlite";
import { randomUUID } from "node:crypto";
import { mkdirSync } from "node:fs";
import { dirname } from "node:path";
import {
DEFAULT_TITLE,
type DrawingMeta,
type DrawingPublication,
type DrawingRecord,
type ScenePayload,
} from "../core/shared";
import { emptyScene, normalizeScene, normalizeTitle } from "../core/scene";
type DrawingRow = {
id: string;
title: string;
data: string;
createdAt: string;
updatedAt: string;
revision: number;
};
type DrawingMetaRow = Omit<DrawingRow, "data">;
type DrawingPublicationRow = {
publicEnabled: number;
publicSlug: string | null;
};
type PublicDrawingRow = {
title: string;
data: string;
};
export type DrawingUpdateResult =
| { ok: true; drawing: DrawingRecord }
| { ok: false; reason: "not_found" }
| { ok: false; reason: "conflict"; drawing: DrawingRecord };
export type DrawingPublicationUpdateResult =
| { ok: true; publication: DrawingPublication }
| { ok: false; reason: "not_found" }
| { ok: false; reason: "slug_conflict" };
export type DrawingStore = ReturnType<typeof createDrawingStore>;
function createId(): string {
return randomUUID().replaceAll("-", "").slice(0, 12);
}
function resolveDatabasePath(): string {
if (process.env.DATABASE_PATH) {
return process.env.DATABASE_PATH;
}
try {
mkdirSync("/data", { recursive: true });
return "/data/excalidraw.sqlite";
} catch {
return `${process.cwd()}/data/excalidraw.sqlite`;
}
}
function readMeta(row: DrawingMetaRow | null | undefined): DrawingMeta | null {
if (!row) {
return null;
}
return {
id: row.id,
title: row.title,
createdAt: row.createdAt,
updatedAt: row.updatedAt,
revision: row.revision,
};
}
function readPublication(
row: DrawingPublicationRow | null | undefined,
): DrawingPublication | null {
if (!row) {
return null;
}
if (row.publicEnabled !== 1 || !row.publicSlug) {
return { enabled: false };
}
return {
enabled: true,
slug: row.publicSlug,
};
}
function readPublicDrawing(row: PublicDrawingRow | null | undefined) {
if (!row) {
return null;
}
let scene: ScenePayload;
try {
scene = normalizeScene(JSON.parse(row.data));
} catch (error) {
const message =
error instanceof Error ? error.message : "Unknown scene parsing error";
throw new Error(`Invalid stored public scene: ${message}`);
}
return {
title: row.title,
...scene,
};
}
function readRow(row: DrawingRow | null | undefined): DrawingRecord | null {
if (!row) {
return null;
}
let scene: ScenePayload;
try {
scene = normalizeScene(JSON.parse(row.data));
} catch (error) {
const message =
error instanceof Error ? error.message : "Unknown scene parsing error";
throw new Error(`Invalid stored scene for drawing ${row.id}: ${message}`);
}
return {
...readMeta(row)!,
scene,
};
}
function ensurePublicationColumns(db: Database) {
const columns = db.query("PRAGMA table_info(drawings)").all() as Array<{
name: string;
}>;
const names = new Set(columns.map((column) => column.name));
if (!names.has("public_enabled")) {
db.exec(
"ALTER TABLE drawings ADD COLUMN public_enabled INTEGER NOT NULL DEFAULT 0",
);
}
if (!names.has("public_slug")) {
db.exec("ALTER TABLE drawings ADD COLUMN public_slug TEXT");
}
}
function isSlugConflictError(error: unknown): boolean {
return (
error instanceof Error &&
error.message.includes("UNIQUE constraint failed: drawings.public_slug")
);
}
export function createDrawingStore(databasePath = resolveDatabasePath()) {
mkdirSync(dirname(databasePath), { recursive: true });
const db = new Database(databasePath, { create: true, strict: true });
db.exec(`
PRAGMA journal_mode = WAL;
CREATE TABLE IF NOT EXISTS drawings (
id TEXT PRIMARY KEY,
title TEXT NOT NULL,
data TEXT NOT NULL,
created_at TEXT NOT NULL DEFAULT CURRENT_TIMESTAMP,
updated_at TEXT NOT NULL DEFAULT CURRENT_TIMESTAMP,
revision INTEGER NOT NULL DEFAULT 0,
public_enabled INTEGER NOT NULL DEFAULT 0,
public_slug TEXT
);
CREATE INDEX IF NOT EXISTS drawings_updated_at_idx
ON drawings(updated_at DESC, created_at DESC);
`);
ensurePublicationColumns(db);
db.exec(`
CREATE UNIQUE INDEX IF NOT EXISTS drawings_public_slug_active_idx
ON drawings(public_slug)
WHERE public_enabled = 1 AND public_slug IS NOT NULL;
`);
const listQuery = db.query(`
SELECT
id,
title,
created_at AS createdAt,
updated_at AS updatedAt,
revision
FROM drawings
ORDER BY updated_at DESC, created_at DESC
`);
const getQuery = db.query(`
SELECT
id,
title,
data,
created_at AS createdAt,
updated_at AS updatedAt,
revision
FROM drawings
WHERE id = ?1
`);
const createQuery = db.query(`
INSERT INTO drawings (id, title, data)
VALUES (?1, ?2, ?3)
`);
const updateSceneQuery = db.query(`
UPDATE drawings
SET data = ?2, updated_at = CURRENT_TIMESTAMP, revision = revision + 1
WHERE id = ?1
`);
const updateTitleQuery = db.query(`
UPDATE drawings
SET title = ?2, updated_at = CURRENT_TIMESTAMP, revision = revision + 1
WHERE id = ?1
`);
const updateBothQuery = db.query(`
UPDATE drawings
SET title = ?2, data = ?3, updated_at = CURRENT_TIMESTAMP, revision = revision + 1
WHERE id = ?1
`);
const updateSceneExpectedQuery = db.query(`
UPDATE drawings
SET data = ?2, updated_at = CURRENT_TIMESTAMP, revision = revision + 1
WHERE id = ?1 AND revision = ?3
`);
const updateTitleExpectedQuery = db.query(`
UPDATE drawings
SET title = ?2, updated_at = CURRENT_TIMESTAMP, revision = revision + 1
WHERE id = ?1 AND revision = ?3
`);
const updateBothExpectedQuery = db.query(`
UPDATE drawings
SET title = ?2, data = ?3, updated_at = CURRENT_TIMESTAMP, revision = revision + 1
WHERE id = ?1 AND revision = ?4
`);
const deleteQuery = db.query(`
DELETE FROM drawings
WHERE id = ?1
`);
const getPublicationQuery = db.query(`
SELECT
public_enabled AS publicEnabled,
public_slug AS publicSlug
FROM drawings
WHERE id = ?1
`);
const publishQuery = db.query(`
UPDATE drawings
SET
public_enabled = 1,
public_slug = ?2
WHERE id = ?1
`);
const disablePublicationQuery = db.query(`
UPDATE drawings
SET
public_enabled = 0,
public_slug = NULL
WHERE id = ?1
`);
const getPublicDrawingQuery = db.query(`
SELECT
title,
data
FROM drawings
WHERE public_enabled = 1 AND public_slug = ?1
`);
function listDrawings(): DrawingMeta[] {
return (listQuery.all() as DrawingMetaRow[]).map((row) => readMeta(row)!);
}
function getDrawing(id: string): DrawingRecord | null {
return readRow(getQuery.get(id) as DrawingRow | null | undefined);
}
function createDrawing(title = DEFAULT_TITLE): DrawingRecord {
const id = createId();
createQuery.run(id, normalizeTitle(title), JSON.stringify(emptyScene()));
return getDrawing(id)!;
}
function getLatestDrawing(): DrawingMeta | null {
return listDrawings()[0] ?? null;
}
function ensureInitialDrawing(): DrawingMeta {
return getLatestDrawing() ?? createDrawing();
}
function updateDrawing(
id: string,
update: { scene?: ScenePayload; title?: string; expectedRevision?: number },
): DrawingUpdateResult {
const hasScene = update.scene !== undefined;
const hasTitle = update.title !== undefined;
const existingRow = getQuery.get(id) as DrawingRow | null | undefined;
if (!existingRow) {
return { ok: false, reason: "not_found" };
}
const existing = readRow(existingRow)!;
if (!hasScene && !hasTitle) {
return { ok: true, drawing: existing };
}
const nextTitle = hasTitle
? normalizeTitle(update.title)
: existingRow.title;
const nextScene = hasScene
? JSON.stringify(update.scene)
: existingRow.data;
const titleChanged = nextTitle !== existingRow.title;
const sceneChanged = nextScene !== existingRow.data;
if (!titleChanged && !sceneChanged) {
return { ok: true, drawing: existing };
}
if (
update.expectedRevision !== undefined &&
update.expectedRevision !== existingRow.revision
) {
return { ok: false, reason: "conflict", drawing: existing };
}
let changes: number;
if (sceneChanged && titleChanged) {
changes =
update.expectedRevision === undefined
? Number(updateBothQuery.run(id, nextTitle, nextScene).changes)
: Number(
updateBothExpectedQuery.run(
id,
nextTitle,
nextScene,
update.expectedRevision,
).changes,
);
} else if (sceneChanged) {
changes =
update.expectedRevision === undefined
? Number(updateSceneQuery.run(id, nextScene).changes)
: Number(
updateSceneExpectedQuery.run(
id,
nextScene,
update.expectedRevision,
).changes,
);
} else {
changes =
update.expectedRevision === undefined
? Number(updateTitleQuery.run(id, nextTitle).changes)
: Number(
updateTitleExpectedQuery.run(
id,
nextTitle,
update.expectedRevision,
).changes,
);
}
const drawing = getDrawing(id);
if (changes > 0 && drawing) {
return { ok: true, drawing };
}
if (!drawing) {
return { ok: false, reason: "not_found" };
}
return { ok: false, reason: "conflict", drawing };
}
function deleteDrawing(id: string): {
deleted: boolean;
next: DrawingMeta | null;
} {
const changes = Number(deleteQuery.run(id).changes);
if (changes === 0) {
return { deleted: false, next: null };
}
return {
deleted: true,
next: ensureInitialDrawing(),
};
}
function getDrawingPublication(id: string): DrawingPublication | null {
return readPublication(
getPublicationQuery.get(id) as DrawingPublicationRow | null | undefined,
);
}
function publishDrawing(
id: string,
publication: { slug: string },
): DrawingPublicationUpdateResult {
try {
const changes = Number(publishQuery.run(id, publication.slug).changes);
if (changes === 0) {
return { ok: false, reason: "not_found" };
}
} catch (error) {
if (isSlugConflictError(error)) {
return { ok: false, reason: "slug_conflict" };
}
throw error;
}
return {
ok: true,
publication: getDrawingPublication(id)!,
};
}
function disableDrawingPublication(
id: string,
): DrawingPublicationUpdateResult {
const changes = Number(disablePublicationQuery.run(id).changes);
if (changes === 0) {
return { ok: false, reason: "not_found" };
}
return {
ok: true,
publication: { enabled: false },
};
}
function getPublicDrawing(slug: string) {
return readPublicDrawing(
getPublicDrawingQuery.get(slug) as PublicDrawingRow | null | undefined,
);
}
function close() {
db.close(false);
}
return {
databasePath,
close,
listDrawings,
getDrawing,
createDrawing,
getLatestDrawing,
ensureInitialDrawing,
updateDrawing,
deleteDrawing,
getDrawingPublication,
publishDrawing,
disableDrawingPublication,
getPublicDrawing,
};
}
let defaultStore: DrawingStore | null = null;
export function getDefaultDrawingStore(): DrawingStore {
defaultStore ??= createDrawingStore();
return defaultStore;
}