release: WRNexusJS 0.3.0

packages/core/src/tenant.ts

@@ -0,0 +1,56 @@
+import type { Context, Middleware } from "./context.ts";
+
+export interface Tenant {
+  id: string;
+  slug?: string;
+  name?: string;
+  metadata?: Record<string, unknown>;
+}
+
+export type TenantResolver = (ctx: Context) => Tenant | null | Promise<Tenant | null>;
+
+export interface TenantMiddlewareOptions {
+  required?: boolean;
+  status?: number;
+}
+
+export function tenantMiddleware(
+  resolveTenant: TenantResolver,
+  options: TenantMiddlewareOptions = {},
+): Middleware {
+  return async (ctx, next) => {
+    const tenant = await resolveTenant(ctx);
+    ctx.tenant = tenant ?? undefined;
+    if (!tenant && options.required !== false) {
+      return new Response("Tenant not found", { status: options.status ?? 404 });
+    }
+    return next();
+  };
+}
+
+export function tenantFromSubdomain(
+  lookup: (slug: string, ctx: Context) => Tenant | null | Promise<Tenant | null>,
+  rootDomains: string[] = [],
+): TenantResolver {
+  return async (ctx) => {
+    const host = ctx.url.hostname.toLowerCase();
+    const root = rootDomains.find((domain) => host === domain || host.endsWith(`.${domain}`));
+    const slug = root ? host.slice(0, -(root.length + 1)) : host.split(".")[0];
+    if (!slug || slug === host || slug === "www") return null;
+    return lookup(slug, ctx);
+  };
+}
+
+export function requireTenant(ctx: Context): Tenant {
+  if (!ctx.tenant)
+    throw new Error("WRN-TENANT-REQUIRED: tenant middleware has not resolved a tenant.");
+  return ctx.tenant;
+}
+
+/** Wrap a repository so every operation receives the current tenant id. */
+export function tenantScope<T extends object>(
+  tenant: Tenant,
+  repository: T,
+): T & { tenantId: string } {
+  return Object.assign(Object.create(repository), { tenantId: tenant.id });
+}