I have a custom rewrite rule which rewrites /wp-content/themes/my-theme/manifest.json to /index.php?manifest=true. This generates some JSON code for progressive web app functionality, and generally works great.
On a multisite install, however, the manifest loads correctly, but still sends a 404 header. I verified that this specific theme does work fine with a normal WordPress site, but in a multisite install, it always seems to send the 404 header.
Some notes:
- I’ve tried using
status_header(200), andheader("HTTP/1.1 200 OK")manually, but neither of those make a difference - I’ve tried setting
$wp->is_404tofalse, but that does nothing - I’ve flushed the permalinks, but that does nothing
Rewrite Rule PHP:
// set up rewirte rules for PWA functionality
function fvpd_pwa_rewrite_rules() {
add_rewrite_endpoint("manifest", EP_NONE);
add_rewrite_rule(substr(parse_url(get_template_directory_uri(), PHP_URL_PATH), 1) . "/manifest\.json$", "index.php?manifest=true", "top");
}
add_action("init", "fvpd_pwa_rewrite_rules");
manifest.json PHP:
// construct a manifest when the user visits {theme_folder}/manifest.json
function fvpd_construct_manifest() {
if (get_query_var("manifest")) {
header("Content-Type: application/json");
$name = fvpd_get_field("full_name", "pwa");
$short_name = fvpd_get_field("short_name", "pwa");
$background_color = fvpd_get_field("background_color", "pwa");
$theme_color = fvpd_get_field("theme_color", "pwa");
$manifest = array(
"start_url" => "https://wordpress.stackexchange.com/",
"display" => "standalone",
"name" => $name ? $name : "Fox Valley Park District - DEV",
"short_name" => $short_name ? $short_name : "FVPD",
"background_color" => $background_color ? $background_color : "#E58F1A",
"theme_color" => $theme_color ? $theme_color : "#E58F1A",
"icons" => array(
array(
"src" => get_theme_file_uri("assets/media/android/splash-icon-512x512.png"),
"type" => "image/png",
"sizes" => "512x512",
),
array(
"src" => get_theme_file_uri("assets/media/android/launcher-icon-192x192.png"),
"type" => "image/png",
"sizes" => "192x192",
),
array(
"src" => get_theme_file_uri("assets/media/android/launcher-icon-144x144.png"),
"type" => "image/png",
"sizes" => "144x144",
),
array(
"src" => get_theme_file_uri("assets/media/android/launcher-icon-96x96.png"),
"type" => "image/png",
"sizes" => "96x96",
),
array(
"src" => get_theme_file_uri("assets/media/android/launcher-icon-72x72.png"),
"type" => "image/png",
"sizes" => "72x72",
),
array(
"src" => get_theme_file_uri("assets/media/android/launcher-icon-48x48.png"),
"type" => "image/png",
"sizes" => "48x48",
),
),
);
echo json_encode($manifest); exit;
}
}
add_action("wp", "fvpd_construct_manifest");
URL in questions:
https://www.foxvalleyparkdistrict.org/wp-content/themes/fox-valley-park-district/manifest.json
This does not affect my other custom rewrite, which points /offline/ to load a custom template.
https://www.foxvalleyparkdistrict.org/offline/
Why is the 404 header being sent, and how can I fix it?
UPDATE 1:
I tried some of the advice below, but to no avail. I do have some additional information that may help, however. I tested changing the rewrite to /manifest.json instead of /wp-content/themes/my-theme/manifest.json, and that actually worked! This gave me an idea, and so I tried the following:
| URL | Status | Folder Exists | WordPress Folder |
|:--------------------------:|:------:|:-------------:|:----------------:|
| /manifest.json | 200 | N/A | N/A |
| /wp-admin/manifest.json | 404 | true | true |
| /wp-content/manifest.json | 404 | true | true |
| /wp-includes/manifest.json | 404 | true | true |
| /cgi-bin/manifest.json | 403 | true | false |
| /custom/manifest.json | 200 | false | false |
| /custom/manifest.json | 200 | true | false |
It seems that if the rewrite is returning a 404 header only when set to an existing WordPress folder. My suspicion is that the rewrite engine is partially ignoring rules to /wp-* folders.
I may end up just keeping the rewrite at /manifest.json, but that creatures a problem if in the future we where to set up additional sites like https://example.com/second-site/, although that could probably be fixed by rewriting to the WordPress root instead of the server root.
UPDATE 2: .htaccess contents is visible here: https://gist.github.com/JacobDB/1531b75c8b8c79117516019225bb7732