fix(news): enforce shared comment publication and moderation rules

src/actions/article-comments.ts

@@ -1,15 +1,11 @@
 "use server";
 
-import { eq } from "drizzle-orm";
 import { revalidatePath } from "next/cache";
 import { redirect } from "next/navigation";
 import { auth } from "@/lib/auth";
-import { db, WebsiteArticleComments, WebsiteArticles } from "@/lib/db";
-import { clientIp, rateLimit } from "@/lib/rate-limit";
-import { isAllowed } from "@/lib/services/moderation";
-
-// website_article_comments.comment is VARCHAR(255); keep the write within bounds.
-const COMMENT_MAX = 255;
+import { sessionUserId } from "@/lib/auth/session-user";
+import { logger } from "@/lib/logger";
+import { submitArticleComment } from "@/lib/services/article-comment-submission";
 
 type CommentOutcome =
 	| "posted"
@@ -31,86 +27,54 @@ function isNextRedirect(e: unknown): boolean {
 		!!e &&
 		typeof e === "object" &&
 		"digest" in e &&
-		typeof (e as { digest?: unknown }).digest === "string" &&
-		(e as { digest: string }).digest.startsWith("NEXT_REDIRECT")
+		typeof e.digest === "string" &&
+		e.digest.startsWith("NEXT_REDIRECT")
 	);
 }
 
-/**
- * Post a comment on a news article as the SIGNED-IN user. The author id is read
- * from the session (re-fetched via auth()), never from the submitted FormData,
- * so a crafted form cannot post as another account. The articleId comes from the
- * form and is validated as a BigInt (website_articles.id is UNSIGNED BIGINT).
- *
- * Errors redirect back with a machine-readable ?error= code; success redirects
- * with ?comment=posted.
- */
+/** The signed-in session determines ownership; form-supplied author IDs are ignored. */
 export async function postComment(formData: FormData): Promise<void> {
-	const slugHint = String(formData.get("slug") ?? "")
+	let slug = String(formData.get("slug") ?? "")
 		.normalize("NFC")
 		.trim();
-
 	let outcome: CommentOutcome = "error";
-	let slug = slugHint;
-
 	try {
 		const session = await auth();
-		if (!session?.user?.id) {
-			redirect("/login");
-		}
-
-		const userId = Number(session.user.id);
-		if (!Number.isFinite(userId) || userId <= 0) {
-			redirect("/login");
-		}
-
-		await clientIp();
-		if (!(await rateLimit(`comment:${userId}`, 5, 30_000)).ok) {
-			outcome = "ratelimit";
-		} else {
-			const comment = String(formData.get("comment") ?? "")
-				.normalize("NFC")
-				.trim()
-				.slice(0, COMMENT_MAX);
-			if (!comment) {
-				outcome = "empty";
-			} else if (!(await isAllowed(comment)).ok) {
-				outcome = "moderated";
-			} else {
-				const articleIdRaw = String(formData.get("articleId") ?? "")
+		const userId = sessionUserId(session?.user?.id);
+		if (!userId) redirect("/login");
+		const result = await submitArticleComment({
+			userId,
+			target: {
+				id: String(formData.get("articleId") ?? "")
 					.normalize("NFC")
-					.trim();
-				if (!/^\d+$/.test(articleIdRaw)) {
-					outcome = "invalid";
-				} else {
-					const articleId = BigInt(articleIdRaw);
-					const [article] = await db
-						.select({ slug: WebsiteArticles.slug })
-						.from(WebsiteArticles)
-						.where(eq(WebsiteArticles.id, articleId))
-						.limit(1);
-					if (!article) {
-						outcome = "not_found";
-					} else {
-						slug = article.slug;
-						const now = new Date();
-						await db.insert(WebsiteArticleComments).values({
-							articleId,
-							userId,
-							comment,
-							createdAt: now,
-							updatedAt: now,
-						});
-						outcome = "posted";
-					}
-				}
-			}
+					.trim(),
+			},
+			comment: formData.get("comment"),
+		});
+		if (result.ok) {
+			slug = result.slug;
+			outcome = "posted";
+		} else {
+			outcome = result.reason === "too_long" ? "invalid" : result.reason;
 		}
-	} catch (e) {
-		if (isNextRedirect(e)) throw e;
-		outcome = "error";
+	} catch (error) {
+		if (isNextRedirect(error)) throw error;
+		// Driver errors can include SQL and comment text: retain only safe context.
+		logger.error("Article comment submission failed", {
+			module: "article-comments",
+			channel: "site",
+		});
 	}
 
-	if (slug) revalidatePath(`/news/${slug}`);
+	if (outcome === "posted") {
+		try {
+			revalidatePath(`/news/${slug}`);
+		} catch {
+			logger.error("Article comment refresh failed", {
+				module: "article-comments",
+				channel: "site",
+			});
+		}
+	}
 	commentRedirect(slug, outcome);
 }

src/app/api/articles/[slug]/comment/route.ts

@@ -1,60 +1,52 @@
-// Public REST API — post a comment on an article as the Bearer-authed user.
-//
-// POST /api/articles/:slug/comment — looks up the website_article by slug for
-// its id, then inserts a website_article_comments row owned by the user behind
-// the Authorization: Bearer token. Comment is required, non-empty, max 255
-// chars (matches the VARCHAR(255) column). Fails soft — never returns a 500 for
-// DB issues, just a generic error envelope.
-
-import { eq } from "drizzle-orm";
-import { apiError, apiJson } from "@/lib/api";
+// Public REST API: comments belong to the authenticated Bearer token's user.
+import { apiError, apiJson, apiUnavailable } from "@/lib/api";
 import { bearerUserId } from "@/lib/api-auth";
-import { db, WebsiteArticleComments, WebsiteArticles } from "@/lib/db";
-import { rateLimit } from "@/lib/rate-limit";
+import { logger } from "@/lib/logger";
+import { submitArticleComment } from "@/lib/services/article-comment-submission";
 
 export async function POST(
 	req: Request,
 	{ params }: { params: Promise<{ slug: string }> },
 ) {
-	const uid = await bearerUserId(req, ["articles:write"]);
-	if (!uid) return apiError("Unauthorized", 401);
-
-	if (!(await rateLimit(`article-comment:${uid}`, 10, 60_000)).ok) {
-		return apiError("Too many comments. Please wait a minute.", 429);
-	}
-
-	const { slug } = await params;
-
-	const body = (await req.json().catch(() => ({}))) as { comment?: unknown };
-	const comment = typeof body.comment === "string" ? body.comment.trim() : "";
-	if (!comment) {
-		return apiError("Comment is required", 422);
-	}
-	if (comment.length > 255) {
-		return apiError("Comment may not be longer than 255 characters", 422);
-	}
-
 	try {
-		const [article] = await db
-			.select({ id: WebsiteArticles.id })
-			.from(WebsiteArticles)
-			.where(eq(WebsiteArticles.slug, slug))
-			.limit(1);
-		if (!article) {
-			return apiError("Article not found", 404);
-		}
-
-		const now = new Date();
-		await db.insert(WebsiteArticleComments).values({
-			articleId: article.id,
+		const uid = await bearerUserId(req, ["articles:write"]);
+		if (!uid) return apiError("Unauthorized", 401);
+		const { slug } = await params;
+		const body: unknown = await req.json().catch(() => null);
+		const result = await submitArticleComment({
 			userId: uid,
-			comment,
-			createdAt: now,
-			updatedAt: now,
+			target: { slug },
+			comment:
+				body && typeof body === "object" && "comment" in body
+					? body.comment
+					: undefined,
 		});
-
-		return apiJson({ ok: true });
+		if (result.ok) return apiJson({ ok: true });
+		switch (result.reason) {
+			case "ratelimit": {
+				const response = apiError(
+					"Too many comments. Please wait a minute.",
+					429,
+				);
+				response.headers.set("Retry-After", String(result.retryAfter ?? 30));
+				return response;
+			}
+			case "empty":
+				return apiError("Comment is required", 422);
+			case "too_long":
+				return apiError("Comment may not be longer than 255 characters", 422);
+			case "moderated":
+				return apiError("Comment was blocked by moderation", 422);
+			case "invalid":
+			case "not_found":
+				return apiError("Article not found", 404);
+		}
 	} catch {
-		return apiError("Could not post comment", 400);
+		// Driver errors may contain SQL and user content; log a safe diagnostic.
+		logger.error("Article comment submission failed", {
+			module: "article-comments",
+			channel: "api",
+		});
+		return apiUnavailable("Could not post comment");
 	}
 }

src/lib/services/article-comment-submission.test.ts

@@ -0,0 +1,257 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+
+const state = vi.hoisted(() => ({
+	userId: 100,
+	sessionId: "100" as string | null,
+	article: {
+		id: "12",
+		slug: "public-news",
+		status: "published",
+		publishAt: null as Date | null,
+	},
+	words: [] as string[],
+	queries: [] as string[],
+	writes: [] as unknown[][],
+	transactions: 0,
+	lockedWrites: [] as boolean[],
+	inTransaction: false,
+	failRead: false,
+	failWrite: false,
+	withdrawDuringModeration: false,
+	log: vi.fn(),
+	revalidate: vi.fn(),
+}));
+
+vi.mock("@/lib/db", async () => {
+	const schema = await import("@/db/schema");
+	const { drizzle } = await import("drizzle-orm/mysql-proxy");
+	const db = drizzle(async (query, parameters) => {
+		state.queries.push(query);
+		if (query.includes(" from `website_wordfilter`")) {
+			if (state.withdrawDuringModeration) state.article.status = "draft";
+			return { rows: state.words.map((word) => [word]) };
+		}
+		if (
+			query.startsWith("select ") &&
+			query.includes(" from `website_articles`")
+		) {
+			if (state.failRead) throw new Error("private SQL and comment payload");
+			if (
+				query.includes("`status` = ?") &&
+				state.article.status !== "published"
+			)
+				return { rows: [] };
+			if (
+				query.includes("<= NOW()") &&
+				state.article.publishAt &&
+				state.article.publishAt > new Date()
+			)
+				return { rows: [] };
+			if (
+				String(parameters[0]) !== state.article.id &&
+				parameters[0] !== state.article.slug
+			)
+				return { rows: [] };
+			const columns = query
+				.slice(7, query.indexOf(" from "))
+				.split(", ")
+				.map((column) => column.replaceAll("`", ""));
+			return {
+				rows: [columns.map((column) => state.article[column as "id" | "slug"])],
+			};
+		}
+		if (query.startsWith("insert into `website_article_comments`")) {
+			if (state.failWrite) throw new Error("private SQL and comment payload");
+			state.writes.push(parameters);
+			state.lockedWrites.push(
+				state.inTransaction &&
+					state.queries.some((sql) => sql.endsWith("for update")),
+			);
+			return { rows: [{ insertId: 1, affectedRows: 1 }] };
+		}
+		return { rows: [] };
+	});
+	Object.defineProperty(db, "transaction", {
+		value: async (callback: (tx: typeof db) => Promise<unknown>) => {
+			state.transactions += 1;
+			state.inTransaction = true;
+			try {
+				return await callback(db);
+			} finally {
+				state.inTransaction = false;
+			}
+		},
+	});
+	return { ...schema, db };
+});
+vi.mock("@/lib/auth", () => ({
+	auth: async () => ({ user: { id: state.sessionId } }),
+}));
+vi.mock("@/lib/api-auth", () => ({
+	bearerUserId: async () => state.userId || null,
+}));
+vi.mock("@/env", () => ({ env: {} }));
+vi.mock("@/lib/redis", () => ({ redis: null }));
+vi.mock("@/lib/logger", () => ({ logger: { error: state.log } }));
+vi.mock("next/cache", () => ({ revalidatePath: state.revalidate }));
+vi.mock("next/navigation", () => ({
+	redirect: (url: string) => {
+		throw Object.assign(new Error(url), {
+			digest: `NEXT_REDIRECT;replace;${url};307;`,
+		});
+	},
+}));
+
+import { postComment } from "@/actions/article-comments";
+import { POST } from "@/app/api/articles/[slug]/comment/route";
+import { reloadWordFilter } from "@/lib/services/moderation";
+
+function api(comment: unknown = "Hello", slug = "public-news") {
+	return POST(
+		new Request("https://hotel.test/api/articles/public-news/comment", {
+			method: "POST",
+			headers: { "content-type": "application/json" },
+			body: JSON.stringify({ comment, userId: 999 }),
+		}),
+		{ params: Promise.resolve({ slug }) },
+	);
+}
+async function site(comment = "Hello", articleId = "12") {
+	const form = new FormData();
+	form.set("comment", comment);
+	form.set("articleId", articleId);
+	form.set("slug", "public-news");
+	form.set("userId", "999");
+	try {
+		await postComment(form);
+	} catch (error) {
+		if (error instanceof Error && "digest" in error) return error.message;
+		throw error;
+	}
+	throw new Error("Expected action redirect");
+}
+
+beforeEach(() => {
+	state.userId += 1;
+	state.sessionId = String(state.userId);
+	state.article = {
+		id: "12",
+		slug: "public-news",
+		status: "published",
+		publishAt: null,
+	};
+	state.words = [];
+	state.queries = [];
+	state.writes = [];
+	state.lockedWrites = [];
+	state.transactions = 0;
+	state.inTransaction = false;
+	state.failRead = false;
+	state.failWrite = false;
+	state.withdrawDuringModeration = false;
+	state.log.mockReset();
+	state.revalidate.mockReset();
+	reloadWordFilter();
+});
+
+describe("article comment entrypoints share publication and abuse policy", () => {
+	it.each(["draft", "scheduled"])(
+		"blocks %s articles through both channels",
+		async (status) => {
+			state.article.status = status;
+			expect(await site()).toBe("/news/public-news?error=not_found");
+			expect((await api()).status).toBe(404);
+			expect(state.writes).toHaveLength(0);
+		},
+	);
+	it("blocks published articles whose scheduled date is still in the future", async () => {
+		state.article.publishAt = new Date(Date.now() + 60_000);
+		expect(await site()).toBe("/news/public-news?error=not_found");
+		expect((await api()).status).toBe(404);
+		expect(state.writes).toHaveLength(0);
+	});
+	it("keeps due articles writable and locks eligibility until each insert", async () => {
+		state.article.publishAt = new Date(Date.now() - 60_000);
+		expect(await site()).toBe("/news/public-news?comment=posted");
+		const response = await api();
+		expect(response.status).toBe(200);
+		expect(await response.json()).toEqual({ ok: true });
+		expect(state.transactions).toBe(2);
+		expect(state.lockedWrites).toEqual([true, true]);
+		expect(state.writes).toHaveLength(2);
+		for (const parameters of state.writes) {
+			expect(parameters).toContain(state.userId);
+			expect(parameters).not.toContain(999);
+		}
+	});
+	it("applies the real configured word filter to both channels", async () => {
+		state.words = ["forbidden"];
+		expect(await site("FORBIDDEN content")).toBe(
+			"/news/public-news?error=moderated",
+		);
+		expect((await api("FORBIDDEN content")).status).toBe(422);
+		expect(state.writes).toHaveLength(0);
+	});
+	it("rechecks publication after moderation completes", async () => {
+		state.withdrawDuringModeration = true;
+		expect((await api()).status).toBe(404);
+		expect(state.writes).toHaveLength(0);
+	});
+	it.each(["site", "api"])(
+		"shares five attempts across channels starting with %s",
+		async (first) => {
+			for (let i = 0; i < 5; i++) {
+				if (first === "site") expect(await site()).toContain("comment=posted");
+				else expect((await api()).status).toBe(200);
+			}
+			if (first === "site") expect((await api()).status).toBe(429);
+			else expect(await site()).toBe("/news/public-news?error=ratelimit");
+			expect(state.writes).toHaveLength(5);
+		},
+	);
+	it("normalizes the same text before moderation and persistence", async () => {
+		await site("  cafe\u0301  ");
+		await api("  cafe\u0301  ");
+		expect(state.writes).toHaveLength(2);
+		for (const parameters of state.writes) expect(parameters).toContain("café");
+	});
+	it.each(["failRead", "failWrite"] as const)(
+		"returns safe recoverable errors for %s",
+		async (failure) => {
+			state[failure] = true;
+			expect(await site()).toBe("/news/public-news?error=error");
+			const response = await api();
+			expect(response.status).toBe(503);
+			expect(await response.json()).toEqual({
+				error: "Could not post comment",
+			});
+			expect(state.log).toHaveBeenCalledTimes(2);
+			expect(JSON.stringify(state.log.mock.calls)).not.toContain("private SQL");
+			expect(state.writes).toHaveLength(0);
+		},
+	);
+	it("rejects missing articles without inserting", async () => {
+		expect(await site("Hello", "42")).toContain("error=not_found");
+		expect((await api("Hello", "missing")).status).toBe(404);
+		expect(state.writes).toHaveLength(0);
+	});
+	it("keeps sessions mandatory for forms and bearer authentication for API", async () => {
+		state.userId = 0;
+		state.sessionId = null;
+		expect(await site()).toBe("/login");
+		expect((await api()).status).toBe(401);
+		expect(state.writes).toHaveLength(0);
+	});
+	it("rejects oversized input before insertion without silently truncating", async () => {
+		expect(await site("a".repeat(256))).toContain("error=invalid");
+		expect((await api("a".repeat(256))).status).toBe(422);
+		expect(state.writes).toHaveLength(0);
+	});
+	it("does not turn a committed comment into a retry when revalidation fails", async () => {
+		state.revalidate.mockImplementation(() => {
+			throw new Error("cache unavailable");
+		});
+		expect(await site()).toContain("comment=posted");
+		expect(state.writes).toHaveLength(1);
+	});
+});

src/lib/services/article-comment-submission.ts

@@ -0,0 +1,87 @@
+import "server-only";
+import { and, eq, or, sql } from "drizzle-orm";
+import { db, WebsiteArticleComments, WebsiteArticles } from "@/lib/db";
+import { rateLimit } from "@/lib/rate-limit";
+import { isAllowed } from "@/lib/services/moderation";
+
+export type ArticleCommentTarget = { id: string } | { slug: string };
+export type ArticleCommentResult =
+	| { ok: true; slug: string }
+	| {
+			ok: false;
+			reason:
+				| "empty"
+				| "too_long"
+				| "invalid"
+				| "moderated"
+				| "ratelimit"
+				| "not_found";
+			retryAfter?: number;
+	  };
+
+/** Authenticated callers share the same quota and uncached publication check. */
+export async function submitArticleComment({
+	userId,
+	target,
+	comment: rawComment,
+}: {
+	userId: number;
+	target: ArticleCommentTarget;
+	comment: unknown;
+}): Promise<ArticleCommentResult> {
+	if (!Number.isSafeInteger(userId) || userId <= 0)
+		return { ok: false, reason: "invalid" };
+	// Preserve the site's five-attempt burst; API and form consume one bucket.
+	const limit = await rateLimit(`comment:${userId}`, 5, 30_000);
+	if (!limit.ok)
+		return { ok: false, reason: "ratelimit", retryAfter: limit.retryAfter };
+
+	const comment =
+		typeof rawComment === "string" ? rawComment.normalize("NFC").trim() : "";
+	if (!comment) return { ok: false, reason: "empty" };
+	if (comment.length > 255) return { ok: false, reason: "too_long" };
+
+	let articleId = 0n;
+	if ("id" in target) {
+		if (!/^\d{1,20}$/.test(target.id)) return { ok: false, reason: "invalid" };
+		articleId = BigInt(target.id);
+		if (articleId <= 0n || articleId > 18446744073709551615n)
+			return { ok: false, reason: "invalid" };
+	} else if (!target.slug || target.slug.length > 255) {
+		return { ok: false, reason: "invalid" };
+	}
+	if (!(await isAllowed(comment)).ok) return { ok: false, reason: "moderated" };
+
+	// Moderate before locking: the optional remote check can take several seconds.
+	// A locking read sees current publication state and serializes withdrawal/deletion
+	// with this insert, rather than trusting a prior page or cached article lookup.
+	return db.transaction(async (tx): Promise<ArticleCommentResult> => {
+		const [article] = await tx
+			.select({ id: WebsiteArticles.id, slug: WebsiteArticles.slug })
+			.from(WebsiteArticles)
+			.where(
+				and(
+					"slug" in target
+						? eq(WebsiteArticles.slug, target.slug)
+						: eq(WebsiteArticles.id, articleId),
+					eq(WebsiteArticles.status, "published"),
+					or(
+						sql`${WebsiteArticles.publishAt} IS NULL`,
+						sql`${WebsiteArticles.publishAt} <= NOW()`,
+					),
+				),
+			)
+			.limit(1)
+			.for("update");
+		if (!article) return { ok: false, reason: "not_found" };
+		const now = new Date();
+		await tx.insert(WebsiteArticleComments).values({
+			articleId: article.id,
+			userId,
+			comment,
+			createdAt: now,
+			updatedAt: now,
+		});
+		return { ok: true, slug: article.slug };
+	});
+}