| 1 | import { BodyReadError, readBoundedBody } from "@/lib/bounded-body"; |
| 2 | import { NextResponse } from "next/server"; |
| 3 | import { MAX_ENVELOPE_BYTES, validateEnvelope } from "@/lib/telemetry/product-usage"; |
| 4 | |
| 5 | /** |
| 6 | * POST /api/product-telemetry — the website's same-origin forwarder. |
| 7 | * |
| 8 | * Inert without configuration: unless `CODEWHALE_TELEMETRY_INGEST_URL` is set |
| 9 | * to the exact canonical first-party ingest, the route accepts nothing and |
| 10 | * forwards nothing. With it set, a batch is forwarded only when it passes the |
| 11 | * closed-set validator for the `website` surface and fits in 4 KiB. The |
| 12 | * forward sets only a content-type header and the validated body; it does not |
| 13 | * copy client headers. Hosting infrastructure may add transport headers, so |
| 14 | * this is not a claim of network anonymity. Forwarding has a 1.5-second timeout |
| 15 | * with no retry. The response is |
| 16 | * `{ accepted, reason? }`, never the ingest's own body. |
| 17 | * |
| 18 | * The PostHog token, if the ingest has one, lives there. This route never |
| 19 | * holds it. |
| 20 | */ |
| 21 | |
| 22 | export const runtime = "edge"; |
| 23 | |
| 24 | export const CANONICAL_INGEST_URL = "https://telemetry.codewhale.net/v1/telemetry"; |
| 25 | const FORWARD_TIMEOUT_MS = 1500; |
| 26 | |
| 27 | export function ingestUrl(env: Record<string, string | undefined> = process.env): string | null { |
| 28 | const configured = env.CODEWHALE_TELEMETRY_INGEST_URL?.trim(); |
| 29 | return configured === CANONICAL_INGEST_URL ? configured : null; |
| 30 | } |
| 31 | |
| 32 | type Forward = (url: string, body: string, signal: AbortSignal) => Promise<{ ok: boolean }>; |
| 33 | |
| 34 | const defaultForward: Forward = (url, body, signal) => |
| 35 | fetch(url, { |
| 36 | method: "POST", |
| 37 | headers: { "content-type": "application/json" }, |
| 38 | body, |
| 39 | signal, |
| 40 | redirect: "error", |
| 41 | }); |
| 42 | |
| 43 | export async function handleProductTelemetry( |
| 44 | request: Request, |
| 45 | deps: { ingestUrl?: string | null; forward?: Forward } = {}, |
| 46 | ): Promise<Response> { |
| 47 | const target = deps.ingestUrl === undefined ? ingestUrl() : deps.ingestUrl; |
| 48 | const reply = (status: number, accepted: boolean, reason?: string) => |
| 49 | NextResponse.json(reason ? { accepted, reason } : { accepted }, { |
| 50 | status, |
| 51 | headers: { "cache-control": "no-store" }, |
| 52 | }); |
| 53 | |
| 54 | if (!target) return reply(200, false, "disabled"); |
| 55 | |
| 56 | let text: string; |
| 57 | try { |
| 58 | const bytes = await readBoundedBody(request, MAX_ENVELOPE_BYTES); |
| 59 | text = new TextDecoder("utf-8", { fatal: true }).decode(bytes); |
| 60 | } catch (cause) { |
| 61 | if (cause instanceof BodyReadError) { |
| 62 | return reply(cause.status, false, cause.status === 413 ? "too_large" : "invalid_body"); |
| 63 | } |
| 64 | return reply(422, false, "invalid_json"); |
| 65 | } |
| 66 | |
| 67 | let parsed: unknown; |
| 68 | try { |
| 69 | parsed = JSON.parse(text); |
| 70 | } catch { |
| 71 | return reply(422, false, "invalid_json"); |
| 72 | } |
| 73 | const validated = validateEnvelope(parsed, { surfaces: ["website"] }); |
| 74 | if (!validated.ok) return reply(422, false, "schema"); |
| 75 | |
| 76 | const controller = new AbortController(); |
| 77 | const timer = setTimeout(() => controller.abort(), FORWARD_TIMEOUT_MS); |
| 78 | try { |
| 79 | // Re-serialise the validated envelope so only known fields travel. |
| 80 | const response = await (deps.forward ?? defaultForward)( |
| 81 | target, |
| 82 | JSON.stringify(validated.envelope), |
| 83 | controller.signal, |
| 84 | ); |
| 85 | return reply(200, response.ok, response.ok ? undefined : "unavailable"); |
| 86 | } catch { |
| 87 | return reply(200, false, "unavailable"); |
| 88 | } finally { |
| 89 | clearTimeout(timer); |
| 90 | } |
| 91 | } |
| 92 | |
| 93 | export async function POST(request: Request): Promise<Response> { |
| 94 | return handleProductTelemetry(request); |
| 95 | } |
| 96 |