Slug query returns null when post_name is stored as percent-encoded (non-ASCII slugs: Korean, Japanese, etc.) #3582
Description
Description
When WordPress stores post_name (slug) in percent-encoded form (e.g. %eb%b2%a0%ed%8a%b8%eb%82%a8-%ed%8e%b8%ec%9d%98%ec%a0%90 instead of 베트남-편의점), all slug-based queries return null.
Expected: Querying by slug (decoded or encoded) should return the post.
Actual: All slug-based query methods return null. Only DATABASE_ID works.
The WP REST API handles this correctly — GET /wp-json/wp/v2/posts?slug=%eb%b2%a0%ed%8a%b8%eb%82%a8-%ed%8e%b8%ec%9d%98%ec%a0%90 returns the post successfully.
This affects any non-ASCII language where WordPress stores slugs in percent-encoded form (Korean, Japanese, etc.).
Steps to reproduce
- Create a WordPress post with a non-ASCII title (e.g. Korean:
베트남-편의점) - WordPress generates a percent-encoded slug stored in
wp_posts.post_nameas%eb%b2%a0%ed%8a%b8%eb%82%a8-%ed%8e%b8%ec%9d%98%ec%a0%90 - Confirm the post is retrievable via REST API:
GET /wp-json/wp/v2/posts?slug=%eb%b2%a0%ed%8a%b8%eb%82%a8-%ed%8e%b8%ec%9d%98%ec%a0%90
→ Returns the post (works)
- Query via GraphQL — all return
null:
# Decoded Korean slug
{ post(id: "베트남-편의점", idType: SLUG) { databaseId title } }
# → null
# Percent-encoded slug (lowercase)
{ post(id: "%eb%b2%a0%ed%8a%b8%eb%82%a8-%ed%8e%b8%ec%9d%98%ec%a0%90", idType: SLUG) { databaseId title } }
# → null
# Percent-encoded slug (uppercase)
{ post(id: "%EB%B2%A0%ED%8A%B8%EB%82%A8-%ED%8E%B8%EC%9D%98%EC%A0%90", idType: SLUG) { databaseId title } }
# → null
# URI
{ post(id: "/베트남-편의점/", idType: URI) { databaseId title } }
# → null
# nodeByUri
{ nodeByUri(uri: "/베트남-편의점/") { ... on Post { databaseId title } } }
# → null
# postBy
{ postBy(slug: "베트남-편의점") { databaseId title } }
# → null
5/ Only DATABASE_ID works:
{ post(id: "29099", idType: DATABASE_ID) { databaseId title slug } }
# → Returns: { databaseId: 29099, title: "...", slug: "베트남-편의점" }
Additional context
WPGraphQL returns the slug in decoded form ("slug": "베트남-편의점") when queried by DATABASE_ID, yet cannot find the same post when that exact slug is used as input for idType: SLUG.
GraphiQL IDE result:
{
"data": {
"test_slug": null,
"test_id": {
"databaseId": 29099,
"title": "다낭, 나트랑 및 베트남 지역별 편의점 완전 가이드",
"slug": "베트남-편의점"
}
}
}
The root cause appears to be that WPGraphQL does not apply urldecode() when comparing the input slug against the DB-stored post_name. The WP REST API handles this correctly.
WPGraphQL Version
2.9.0
WordPress Version
6.9.1
PHP Version
8.2.27
Additional environment details
Local development environment: Local by Flywheel (macOS)
No additional WPGraphQL extensions installed.
WordPress permalink structure: /%postname%/
Please confirm that you have searched existing issues in the repo.
- Yes
Please confirm that you have disabled ALL plugins except for WPGraphQL.
- Yes
- My issue is with compatibility with a specific WordPress plugin, and I have listed all my installed plugins (and version info) above.