Medplum

// SPDX-FileCopyrightText: Copyright Orangebot, Inc. and Medplum contributors // SPDX-License-Identifier: Apache-2.0 export type HttpMethod = 'GET' | 'POST' | 'PUT' | 'PATCH' | 'DELETE' | 'HEAD' | 'OPTIONS'; export type PathSegment = { value: string; param?: boolean }; export type Route<Handler, Metadata> = { method: HttpMethod; path: PathSegment[]; handler: Handler; data?: Metadata }; export type RouteResult<Handler, Metadata> = { handler: Handler; path: string; params: Record<string, string>; query?: Record<string, string | string[]>; data?: Metadata; }; export class Router<Handler, Metadata> { readonly routes: Route<Handler, Metadata>[] = []; add(method: HttpMethod, pathStr: string, handler: Handler, data?: Metadata): void { const path = pathStr .split('/') .filter((e) => !!e) .map((value) => (value.startsWith(':') ? { value: value.substring(1), param: true } : { value })); this.routes.push({ method, path, handler, data }); } find(method: HttpMethod, pathStr: string): RouteResult<Handler, Metadata> | undefined { const queryStart = pathStr.indexOf('?'); const hasQuery = queryStart > -1; const path = pathStr .substring(0, hasQuery ? queryStart : pathStr.length) .split('/') .filter(Boolean); let bestRoute: Route<Handler, Metadata> | undefined = undefined; let bestScore = -1; for (const route of this.routes) { const score = tryMatch(route, method, path); if (score > bestScore) { bestRoute = route; bestScore = score; } } if (!bestRoute) { return undefined; } return { handler: bestRoute.handler, path: path.join('/'), params: buildParams(bestRoute, path), query: hasQuery ? parseQueryString(pathStr) : undefined, data: bestRoute.data, }; } } function tryMatch<T, U>(route: Route<T, U>, method: HttpMethod, path: string[]): number { if (method !== route.method || path.length !== route.path.length) { return -1; } let score = 0; for (let i = 0; i < path.length; i++) { if (!route.path[i].param) { if (path[i] !== route.path[i].value) { return -1; } score++; } } return score; } function buildParams<T, U>(route: Route<T, U>, path: string[]): Record<string, string> { const params: Record<string, string> = Object.create(null); for (let i = 0; i < path.length; i++) { if (route.path[i].param) { params[route.path[i].value] = path[i]; } } return params; } function parseQueryString(path: string): Record<string, string | string[]> { // Pass in dummy host for parsing purposes. // The host is ignored. const url = new URL(path, 'https://example.com/'); const queryParams = Object.create(null); const raw = url.searchParams; for (const param of raw.keys()) { const values = raw.getAll(param); queryParams[param] = values.length === 1 ? values[0] : values; } return queryParams; }