TenantAssignment and readside filtering

src/lib/db.ts

@@ -82,6 +82,39 @@ const MIGRATION_SQL = `
     content    TEXT NOT NULL,
     updated_at TIMESTAMPTZ NOT NULL DEFAULT now()
   );
+
+  -- ---------------------------------------------------------------------------
+  -- Slice 6: per-tenant user assignments
+  -- ---------------------------------------------------------------------------
+  --
+  -- Each row grants ONE user visibility into ONE tenant within their own
+  -- ZITADEL org. Used to narrow the customer 'user' role from "everything
+  -- in the org" to "only the tenants I've been assigned to". Owners and
+  -- platform users bypass this table entirely.
+  --
+  -- Composite PK is (tenant_name, zitadel_user_id) — a user is either
+  -- assigned to a tenant or not, no degree.
+  --
+  -- The zitadel_org_id column is denormalised onto every row so cascade
+  -- cleanups when a user leaves an org can be expressed as a single
+  -- DELETE WHERE zitadel_org_id=$1 AND zitadel_user_id=$2 — without
+  -- joining tenant_requests. The assigned_by column tracks which user
+  -- (the owner usually) granted the assignment, for audit.
+  --
+  -- Cascade on tenant deletion is enforced in application code (the
+  -- admin delete handler calls removeAllAssignmentsForTenant) rather
+  -- than via FK — there's no FK target, since K8s CRs aren't a Postgres
+  -- table.
+  CREATE TABLE IF NOT EXISTS tenant_user_assignments (
+    tenant_name      TEXT NOT NULL,
+    zitadel_org_id   TEXT NOT NULL,
+    zitadel_user_id  TEXT NOT NULL,
+    assigned_at      TIMESTAMPTZ NOT NULL DEFAULT now(),
+    assigned_by      TEXT NOT NULL,
+    PRIMARY KEY (tenant_name, zitadel_user_id)
+  );
+  CREATE INDEX IF NOT EXISTS idx_tua_user ON tenant_user_assignments(zitadel_user_id);
+  CREATE INDEX IF NOT EXISTS idx_tua_org  ON tenant_user_assignments(zitadel_org_id);
 `;
 
 let migrated = false;
@@ -417,3 +450,150 @@ function mapRow(row: any): TenantRequest {
     updatedAt: row.updated_at?.toISOString?.() ?? row.updated_at,
   };
 }
+
+// ---------------------------------------------------------------------------
+// Slice 6: tenant ↔ user assignments
+// ---------------------------------------------------------------------------
+
+/**
+ * One assignment grants one user visibility into one tenant. Returned
+ * shape is the camelCase mirror of the Postgres row.
+ */
+export interface TenantUserAssignment {
+  tenantName: string;
+  zitadelOrgId: string;
+  zitadelUserId: string;
+  assignedAt: string;
+  assignedBy: string;
+}
+
+function mapAssignmentRow(row: any): TenantUserAssignment {
+  return {
+    tenantName: row.tenant_name,
+    zitadelOrgId: row.zitadel_org_id,
+    zitadelUserId: row.zitadel_user_id,
+    assignedAt: row.assigned_at?.toISOString?.() ?? row.assigned_at,
+    assignedBy: row.assigned_by,
+  };
+}
+
+/**
+ * Returns the set of tenant CR names assigned to the given user.
+ *
+ * Hot path on every read for `user`-role customers, so it's intentionally
+ * a single indexed lookup. The returned array is small (a handful of
+ * tenants per user); callers usually wrap it in a Set.
+ *
+ * Note: this does NOT cross-check the org id — assignments are per-user,
+ * and a user's org context comes from their JWT. If a user's
+ * authorization is revoked at the ZITADEL level, their JWT ceases to
+ * carry the customer role and they can't reach the dashboard at all;
+ * the orphan rows are cleaned up the next time their org membership
+ * is re-evaluated (Slice 7's removeAllAssignmentsForUser).
+ */
+export async function listTenantAssignmentsForUser(
+  userId: string
+): Promise<string[]> {
+  await ensureSchema();
+  const result = await getPool().query<{ tenant_name: string }>(
+    "SELECT tenant_name FROM tenant_user_assignments WHERE zitadel_user_id = $1",
+    [userId]
+  );
+  return result.rows.map((r) => r.tenant_name);
+}
+
+/**
+ * Returns all assignments for a single tenant. Used by the team UI
+ * (Slice 7) to render "who has access to this instance". Includes
+ * `assignedBy` and `assignedAt` for audit display.
+ */
+export async function listAssignmentsForTenant(
+  tenantName: string
+): Promise<TenantUserAssignment[]> {
+  await ensureSchema();
+  const result = await getPool().query(
+    "SELECT * FROM tenant_user_assignments WHERE tenant_name = $1 ORDER BY assigned_at DESC",
+    [tenantName]
+  );
+  return result.rows.map(mapAssignmentRow);
+}
+
+/**
+ * Grant a user access to a tenant. Idempotent — a duplicate INSERT
+ * is silently ignored via ON CONFLICT, and the existing
+ * `assigned_at`/`assigned_by` are preserved (we don't update them on
+ * re-assign).
+ *
+ * Caller is responsible for verifying:
+ *   - The actor (`assignedBy`) holds owner/platform role in `orgId`.
+ *   - The target user (`userId`) is actually a member of the same
+ *     ZITADEL org. We don't validate this here — the team UI fetches
+ *     the org's user list from ZITADEL and selects from it.
+ *   - The tenant CR exists and is labelled with the same `orgId`.
+ */
+export async function addTenantAssignment(params: {
+  tenantName: string;
+  orgId: string;
+  userId: string;
+  assignedBy: string;
+}): Promise<void> {
+  await ensureSchema();
+  await getPool().query(
+    `INSERT INTO tenant_user_assignments
+       (tenant_name, zitadel_org_id, zitadel_user_id, assigned_by)
+     VALUES ($1, $2, $3, $4)
+     ON CONFLICT (tenant_name, zitadel_user_id) DO NOTHING`,
+    [params.tenantName, params.orgId, params.userId, params.assignedBy]
+  );
+}
+
+/**
+ * Revoke a user's access to a tenant. No-op if the row doesn't exist.
+ */
+export async function removeTenantAssignment(
+  tenantName: string,
+  userId: string
+): Promise<void> {
+  await ensureSchema();
+  await getPool().query(
+    "DELETE FROM tenant_user_assignments WHERE tenant_name = $1 AND zitadel_user_id = $2",
+    [tenantName, userId]
+  );
+}
+
+/**
+ * Cascade cleanup: drop ALL assignments for a tenant when the tenant
+ * itself is deleted. Called from the admin delete handler.
+ *
+ * Without this, an orphan row would stick around forever — a future
+ * tenant with the same name (won't happen given Slice 1's UUID-suffix
+ * naming, but defense in depth) would inherit the old assignments.
+ */
+export async function removeAllAssignmentsForTenant(
+  tenantName: string
+): Promise<void> {
+  await ensureSchema();
+  await getPool().query(
+    "DELETE FROM tenant_user_assignments WHERE tenant_name = $1",
+    [tenantName]
+  );
+}
+
+/**
+ * Cascade cleanup: drop ALL assignments for a user within a specific
+ * org. Used by Slice 7's "remove member" flow when an owner kicks a
+ * user out of the org. Scoped by `orgId` so a user with assignments in
+ * org A doesn't lose them when removed from org B (multi-org users
+ * exist when a person registers personally and is also invited to a
+ * company).
+ */
+export async function removeAllAssignmentsForUser(
+  orgId: string,
+  userId: string
+): Promise<void> {
+  await ensureSchema();
+  await getPool().query(
+    "DELETE FROM tenant_user_assignments WHERE zitadel_org_id = $1 AND zitadel_user_id = $2",
+    [orgId, userId]
+  );
+}