fix(core): preserve locale casing in API locale filter (#1551)

.changeset/localecode-preserve-casing.md

@@ -0,0 +1,5 @@
+---
+"emdash": patch
+---
+
+Fixes locale-filtered content and search results for locales with uppercase region or script subtags. Existing content rows saved with lowercased locale values are repaired automatically.

packages/core/src/api/handlers/bylines.ts

@@ -7,7 +7,7 @@ import {
 } from "../../database/repositories/byline.js";
 import { EmDashValidationError, type BylineSummary } from "../../database/repositories/types.js";
 import type { Database } from "../../database/types.js";
-import { getI18nConfig } from "../../i18n/config.js";
+import { getI18nConfig, resolveConfiguredLocale } from "../../i18n/config.js";
 import type { ApiResult } from "../types.js";
 
 // `undefined → null` so a missing field in the create payload matches the
@@ -138,7 +138,8 @@ export async function handleBylineCreate(
 			};
 		}
 
-		const localeErr = rejectUnknownLocale(input.locale);
+		const locale = input.locale ? resolveConfiguredLocale(input.locale) : undefined;
+		const localeErr = rejectUnknownLocale(locale);
 		if (localeErr) return localeErr;
 
 		const repo = new BylineRepository(db);
@@ -160,7 +161,7 @@ export async function handleBylineCreate(
 			sourceGroup = source.translationGroup ?? source.id;
 		}
 
-		const effectiveLocale = input.locale ?? getI18nConfig()?.defaultLocale ?? "en";
+		const effectiveLocale = locale ?? getI18nConfig()?.defaultLocale ?? "en";
 
 		// Translation-group guard: the row-per-locale model (PR #916)
 		// allows exactly one row per (translation_group, locale). Reject
@@ -216,7 +217,7 @@ export async function handleBylineCreate(
 			};
 		}
 
-		const byline = await repo.create(input);
+		const byline = await repo.create({ ...input, locale: effectiveLocale });
 		return { success: true, data: byline };
 	} catch (error) {
 		// Mirror handleBylineUpdate: surface customFields validation

packages/core/src/api/handlers/content.ts

@@ -30,7 +30,7 @@ import { UserRepository } from "../../database/repositories/user.js";
 import { withTransaction } from "../../database/transaction.js";
 import type { Database } from "../../database/types.js";
 import { validateIdentifier } from "../../database/validate.js";
-import { getI18nConfig, isI18nEnabled } from "../../i18n/config.js";
+import { getI18nConfig, isI18nEnabled, resolveConfiguredLocale } from "../../i18n/config.js";
 import { invalidateRedirectCache } from "../../redirects/cache.js";
 import { FTSManager } from "../../search/fts-manager.js";
 import { invalidateTermCache } from "../../taxonomies/index.js";
@@ -269,7 +269,11 @@ async function resolveId(
 	identifier: string,
 	locale?: string,
 ): Promise<string | null> {
-	const item = await repo.findByIdOrSlug(collection, identifier, locale);
+	const item = await repo.findByIdOrSlug(
+		collection,
+		identifier,
+		locale ? resolveConfiguredLocale(locale) : undefined,
+	);
 	return item?.id ?? null;
 }
 
@@ -283,7 +287,11 @@ async function resolveIdIncludingTrashed(
 	identifier: string,
 	locale?: string,
 ): Promise<string | null> {
-	const item = await repo.findByIdOrSlugIncludingTrashed(collection, identifier, locale);
+	const item = await repo.findByIdOrSlugIncludingTrashed(
+		collection,
+		identifier,
+		locale ? resolveConfiguredLocale(locale) : undefined,
+	);
 	return item?.id ?? null;
 }
 
@@ -427,7 +435,7 @@ export async function handleContentList(
 		const repo = new ContentRepository(db);
 		const where: FindManyOptions["where"] = {};
 		if (params.status) where.status = params.status;
-		if (params.locale) where.locale = params.locale;
+		if (params.locale) where.locale = resolveConfiguredLocale(params.locale);
 		if (params.authorId) where.authorId = params.authorId;
 
 		// A date range requires a target column; ignore stray from/to without
@@ -579,7 +587,11 @@ export async function handleContentGet(
 ): Promise<ApiResult<ContentResponse>> {
 	try {
 		const repo = new ContentRepository(db);
-		const item = await repo.findByIdOrSlug(collection, id, locale);
+		const item = await repo.findByIdOrSlug(
+			collection,
+			id,
+			locale ? resolveConfiguredLocale(locale) : undefined,
+		);
 
 		if (!item) {
 			return {
@@ -624,7 +636,11 @@ export async function handleContentGetIncludingTrashed(
 ): Promise<ApiResult<ContentResponse>> {
 	try {
 		const repo = new ContentRepository(db);
-		const item = await repo.findByIdOrSlugIncludingTrashed(collection, id, locale);
+		const item = await repo.findByIdOrSlugIncludingTrashed(
+			collection,
+			id,
+			locale ? resolveConfiguredLocale(locale) : undefined,
+		);
 
 		if (!item) {
 			return {
@@ -706,7 +722,9 @@ export async function handleContentCreate(
 			// Default to the configured site locale rather than the repo's
 			// hard-coded "en" — otherwise non-English default-locale sites
 			// silently create entries in a locale the editor never chose.
-			const effectiveLocale = body.locale ?? getI18nConfig()?.defaultLocale;
+			const effectiveLocale = body.locale
+				? resolveConfiguredLocale(body.locale)
+				: getI18nConfig()?.defaultLocale;
 
 			let slug: string | null | undefined = body.slug;
 			if (!slug) {

packages/core/src/api/handlers/menus.ts

@@ -25,7 +25,7 @@ import {
 	type UpdateMenuItemInput as UpdateMenuItemRepoInput,
 } from "../../database/repositories/menu.js";
 import type { Database } from "../../database/types.js";
-import { getI18nConfig } from "../../i18n/config.js";
+import { getI18nConfig, resolveConfiguredLocale } from "../../i18n/config.js";
 import type { ApiResult } from "../types.js";
 
 // Re-export entity types so route files and tests can import them from the
@@ -89,7 +89,8 @@ async function resolveMenu(
 	name: string,
 	options: { locale?: string },
 ): Promise<ResolveMenuResult> {
-	const matches = await repo.findByName(name, options);
+	const locale = options.locale ? resolveConfiguredLocale(options.locale) : undefined;
+	const matches = await repo.findByName(name, { locale });
 	if (matches.length === 0) {
 		return {
 			success: false,
@@ -124,7 +125,8 @@ export async function handleMenuList(
 ): Promise<ApiResult<MenuListItem[]>> {
 	try {
 		const repo = new MenuRepository(db);
-		const items = await repo.findMany(options);
+		const locale = options.locale ? resolveConfiguredLocale(options.locale) : undefined;
+		const items = await repo.findMany({ locale });
 		return { success: true, data: items };
 	} catch {
 		return {
@@ -175,7 +177,9 @@ export async function handleMenuCreate(
 
 		// Duplicate guard: same (name, locale). Falls back to the configured
 		// defaultLocale to match the column DEFAULT set by migration 036.
-		const effectiveLocale = input.locale ?? getI18nConfig()?.defaultLocale ?? "en";
+		const effectiveLocale = input.locale
+			? resolveConfiguredLocale(input.locale)
+			: (getI18nConfig()?.defaultLocale ?? "en");
 		if (await repo.existsByNameAndLocale(input.name, effectiveLocale)) {
 			return {
 				success: false,
@@ -188,7 +192,7 @@ export async function handleMenuCreate(
 			};
 		}
 
-		const menu = await repo.create(input);
+		const menu = await repo.create({ ...input, locale: effectiveLocale });
 		return { success: true, data: menu };
 	} catch {
 		return {
@@ -212,7 +216,8 @@ export async function handleMenuGet(
 ): Promise<ApiResult<MenuWithItems>> {
 	try {
 		const repo = new MenuRepository(db);
-		const matches = await repo.findByName(name, options);
+		const locale = options.locale ? resolveConfiguredLocale(options.locale) : undefined;
+		const matches = await repo.findByName(name, { locale });
 		if (matches.length === 0) {
 			return {
 				success: false,

packages/core/src/api/handlers/relations.ts

@@ -10,6 +10,7 @@ import {
 import { InvalidCursorError } from "../../database/repositories/types.js";
 import type { ContentItem } from "../../database/repositories/types.js";
 import type { Database } from "../../database/types.js";
+import { resolveConfiguredLocale } from "../../i18n/config.js";
 import { SchemaRegistry } from "../../schema/registry.js";
 import type { ApiResult } from "../types.js";
 
@@ -70,7 +71,10 @@ export async function handleRelationCreate(
 			}
 		}
 
-		const relation = await repo.create(input);
+		const relation = await repo.create({
+			...input,
+			locale: input.locale ? resolveConfiguredLocale(input.locale) : undefined,
+		});
 		return { success: true, data: { relation } };
 	} catch (error) {
 		// A bad `translationOf` makes the repo throw loudly rather than mint an
@@ -127,7 +131,8 @@ export async function handleRelationList(
 ): Promise<ApiResult<{ relations: Relation[] }>> {
 	try {
 		const repo = new RelationRepository(db);
-		const relations = await repo.list(opts.locale);
+		const locale = opts.locale ? resolveConfiguredLocale(opts.locale) : undefined;
+		const relations = await repo.list(locale);
 		return { success: true, data: { relations } };
 	} catch {
 		return {

packages/core/src/api/handlers/taxonomies.ts

@@ -12,6 +12,7 @@ import { ulid } from "ulidx";
 
 import { TaxonomyRepository } from "../../database/repositories/taxonomy.js";
 import type { Database, TaxonomyDefTable } from "../../database/types.js";
+import { resolveConfiguredLocale } from "../../i18n/config.js";
 import { invalidateTaxonomyDefsCache, invalidateTermCache } from "../../taxonomies/index.js";
 import { fetchVisibleTermCounts } from "../../taxonomies/term-counts.js";
 import type { ApiResult } from "../types.js";
@@ -174,8 +175,9 @@ export async function handleTaxonomyList(
 	options: { locale?: string } = {},
 ): Promise<ApiResult<TaxonomyListResponse>> {
 	try {
+		const locale = options.locale ? resolveConfiguredLocale(options.locale) : undefined;
 		let query = db.selectFrom("_emdash_taxonomy_defs").selectAll();
-		if (options.locale !== undefined) query = query.where("locale", "=", options.locale);
+		if (locale !== undefined) query = query.where("locale", "=", locale);
 		const [rows, collectionRows] = await Promise.all([
 			query.execute(),
 			db.selectFrom("_emdash_collections").select("slug").execute(),
@@ -216,6 +218,7 @@ export async function handleTaxonomyCreate(
 	},
 ): Promise<ApiResult<{ taxonomy: TaxonomyDef }>> {
 	try {
+		const locale = input.locale ? resolveConfiguredLocale(input.locale) : undefined;
 		if (!NAME_PATTERN.test(input.name)) {
 			return {
 				success: false,
@@ -265,19 +268,19 @@ export async function handleTaxonomyCreate(
 
 		// Duplicate guard scoped to locale (so the same name can exist in ES
 		// and EN).
-		if (input.locale !== undefined) {
+		if (locale !== undefined) {
 			const existing = await db
 				.selectFrom("_emdash_taxonomy_defs")
 				.select("id")
 				.where("name", "=", input.name)
-				.where("locale", "=", input.locale)
+				.where("locale", "=", locale)
 				.executeTakeFirst();
 			if (existing) {
 				return {
 					success: false,
 					error: {
 						code: "CONFLICT",
-						message: `Taxonomy '${input.name}' already exists in locale '${input.locale}'`,
+						message: `Taxonomy '${input.name}' already exists in locale '${locale}'`,
 					},
 				};
 			}
@@ -293,7 +296,7 @@ export async function handleTaxonomyCreate(
 				label_singular: input.labelSingular ?? null,
 				hierarchical: input.hierarchical ? 1 : 0,
 				collections: JSON.stringify(collections),
-				...(input.locale !== undefined ? { locale: input.locale } : {}),
+				...(locale !== undefined ? { locale } : {}),
 				translation_group: translationGroup ?? id,
 			})
 			.execute();
@@ -390,7 +393,8 @@ export async function handleTermList(
 		if (!lookup.success) return lookup;
 
 		const repo = new TaxonomyRepository(db);
-		const terms = await repo.findByName(taxonomyName, { locale: options.locale });
+		const locale = options.locale ? resolveConfiguredLocale(options.locale) : undefined;
+		const terms = await repo.findByName(taxonomyName, { locale });
 
 		// Counts match what visitors see on the public site: published (or
 		// scheduled-and-due) entries that aren't soft-deleted, scoped to the
@@ -535,6 +539,7 @@ export async function handleTermCreate(
 	},
 ): Promise<ApiResult<TermResponse>> {
 	try {
+		const locale = input.locale ? resolveConfiguredLocale(input.locale) : undefined;
 		// Taxonomy definitions are per-locale, but terms can exist in any locale
 		// regardless of whether the def has been translated there. Look up the
 		// def across all locales — we only care that it *exists*.
@@ -548,14 +553,14 @@ export async function handleTermCreate(
 			input.parentId === "" || input.parentId === undefined ? undefined : input.parentId;
 
 		// Conflict check is scoped to locale (per-locale slugs are unique).
-		const existing = await repo.findBySlug(taxonomyName, input.slug, input.locale);
+		const existing = await repo.findBySlug(taxonomyName, input.slug, locale);
 		if (existing) {
 			return {
 				success: false,
 				error: {
 					code: "CONFLICT",
-					message: input.locale
-						? `Term '${input.slug}' already exists in '${taxonomyName}' (${input.locale})`
+					message: locale
+						? `Term '${input.slug}' already exists in '${taxonomyName}' (${locale})`
 						: `Term with slug '${input.slug}' already exists in taxonomy '${taxonomyName}'`,
 				},
 			};
@@ -594,7 +599,7 @@ export async function handleTermCreate(
 			label: input.label,
 			parentId: parentId ?? undefined,
 			data: input.description ? { description: input.description } : undefined,
-			locale: input.locale,
+			locale,
 			translationOf: input.translationOf,
 		});
 
@@ -635,7 +640,8 @@ export async function handleTermGet(
 ): Promise<ApiResult<TermGetResponse>> {
 	try {
 		const repo = new TaxonomyRepository(db);
-		const term = await repo.findBySlug(taxonomyName, termSlug, options.locale);
+		const locale = options.locale ? resolveConfiguredLocale(options.locale) : undefined;
+		const term = await repo.findBySlug(taxonomyName, termSlug, locale);
 
 		if (!term) {
 			return {
@@ -743,7 +749,8 @@ export async function handleTermUpdate(
 ): Promise<ApiResult<TermResponse>> {
 	try {
 		const repo = new TaxonomyRepository(db);
-		const term = await repo.findBySlug(taxonomyName, termSlug, options.locale);
+		const locale = options.locale ? resolveConfiguredLocale(options.locale) : undefined;
+		const term = await repo.findBySlug(taxonomyName, termSlug, locale);
 
 		if (!term) {
 			return {
@@ -763,7 +770,7 @@ export async function handleTermUpdate(
 
 		// Check if new slug conflicts (per-locale uniqueness).
 		if (newSlug !== undefined && newSlug !== termSlug) {
-			const existing = await repo.findBySlug(taxonomyName, newSlug, options.locale);
+			const existing = await repo.findBySlug(taxonomyName, newSlug, locale);
 			if (existing && existing.id !== term.id) {
 				return {
 					success: false,
@@ -832,7 +839,8 @@ export async function handleTermDelete(
 ): Promise<ApiResult<{ deleted: true }>> {
 	try {
 		const repo = new TaxonomyRepository(db);
-		const term = await repo.findBySlug(taxonomyName, termSlug, options.locale);
+		const locale = options.locale ? resolveConfiguredLocale(options.locale) : undefined;
+		const term = await repo.findBySlug(taxonomyName, termSlug, locale);
 
 		if (!term) {
 			return {

packages/core/src/api/schemas/bylines.ts

@@ -1,6 +1,6 @@
 import { z } from "zod";
 
-import { cursorPaginationQuery, httpUrl } from "./common.js";
+import { cursorPaginationQuery, httpUrl, localeCode } from "./common.js";
 
 /** Slug pattern: lowercase letters, digits, and hyphens; must start with a letter */
 const bylineSlugPattern = /^[a-z][a-z0-9-]*$/;
@@ -81,7 +81,7 @@ export const bylinesListQuery = cursorPaginationQuery
 		 * Rejects empty strings so the picker can't silently fetch the
 		 * unfiltered list when the admin URL has `?locale=` with no value.
 		 */
-		locale: z.string().min(1).optional(),
+		locale: localeCode.optional(),
 	})
 	.meta({ id: "BylinesListQuery" });
 
@@ -102,7 +102,7 @@ export const bylineCreateBody = z
 		 * configured `defaultLocale`) is used. Rejects empty strings — an
 		 * empty locale would create rows no resolver requests.
 		 */
-		locale: z.string().min(1).optional(),
+		locale: localeCode.optional(),
 		/**
 		 * When set, the new row joins the source byline's translation_group
 		 * rather than minting a fresh one. Requires `locale`.
@@ -126,7 +126,7 @@ export const bylineCreateBody = z
 
 export const bylineTranslationCreateBody = z
 	.object({
-		locale: z.string().min(1),
+		locale: localeCode,
 		slug: z
 			.string()
 			.min(1)