Hello,
For some reason when I try to publicly share an image for a forum or whatever, the direct link to the preview will not go to the image. By which I mean:
https://cloud.mynextcloudinstance.com/s/AWmmg8En3knRfRE/preview
Instead, I get a grey screen, and when I go digging in the web browser console I find the error that the item returned a 404 error from the webserver. This happens on Firefox, Edge and Chrome.
This is an odd one and it has been plaguing me a for a little while across NC25, 26 and 27. Honestly I’d be more inclined to be a misconfiguration issue than a bug, as I can’t find any bugs of people having the same issue and someone would have been bound to cross it by now. The annoying this I can’t seem to produce any error in the nextcloud or the nginx logs. Just the nginx access log says that it happened.
e.g.
[11/Jul/2023:15:20:53 -0400] "GET /s/AWmmg8En3knRfRE/preview HTTP/2.0" 404 2 "-" "Mozilla/5.0 (Windows NT 10.0; rv:114.0) Gecko/20100101 Firefox/114.0"
If I had to guess, I’d say it was a webserver misconfiguration issue. But what do you guys think?
Nextcloud version (eg, 20.0.5): 27.0.0
Operating system and version (eg, Ubuntu 20.04): Ubuntu 22.04.02
Apache or nginx version (eg, Apache 2.4.25): nginx/1.25.0
PHP version (eg, 7.4): 8.2.8
Is this the first time you’ve seen this error? (Y/N):Y
Steps to replicate it:
- Share an image
- Go to the direct link (i.e /s/ABCDEF/preview
The output of your Nextcloud log in Admin > Logging:
Nothing relevant triggered by the event
The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):
<?php
$CONFIG = array (
'activity_expire_days' => 14,
'auth.bruteforce.protection.enabled' => true,
'session_lifetime' => 43200,
'auto_logout' => true,
'remember_login_cookie_lifetime' => 86400,
'token_auth_activity_update' => 60,
'blacklisted_files' =>
array (
0 => '.htaccess',
1 => 'Thumbs.db',
2 => 'thumbs.db',
),
'cron_log' => true,
'preview_max_memory' => 4096,
'preview_max_filesize_image' => 256,
'enable_previews' => true,
'enabledPreviewProviders' =>
array (
0 => 'OC\\Preview\\PNG',
1 => 'OC\\Preview\\JPEG',
2 => 'OC\\Preview\\GIF',
3 => 'OC\\Preview\\BMP',
4 => 'OC\\Preview\\XBitmap',
5 => 'OC\\Preview\\Movie',
6 => 'OC\\Preview\\PDF',
7 => 'OC\\Preview\\MP3',
8 => 'OC\\Preview\\TXT',
9 => 'OC\\Preview\\MarkDown',
10 => 'OC\\Preview\\HEIC',
11 => 'OC\\Preview\\TIFF',
12 => 'OC\\Preview\\MKV',
13 => 'OC\\Preview\\MP4',
14 => 'OC\\Preview\\AVI',
15 => 'OC\\Preview\\Image',
),
'trusted_proxies' =>
array (
0 => '127.0.0.1',
1 => '::1',
),
'filesystem_check_changes' => 0,
'filelocking.enabled' => 'true',
'htaccess.RewriteBase' => '/',
'integrity.check.disabled' => false,
'knowledgebaseenabled' => false,
'passwordsalt' => 'REDACTED',
'secret' => 'REDACTED',
'trusted_domains' =>
array (
0 => 'REDACTED',
),
'datadirectory' => '/var/server/nextcloud/data',
'dbtype' => 'pgsql',
'version' => '27.0.0.8',
'overwrite.cli.url' => 'REDACTED',
'overwriteprotocol' => 'https',
'dbname' => 'nextclouddb',
'dbhost' => 'localhost',
'dbport' => '',
'dbtableprefix' => 'oc_',
'dbuser' => 'REDACTED',
'dbpassword' => 'REDACTED',
'installed' => true,
'mail_smtpmode' => 'smtp',
'mail_sendmailmode' => 'REDACTED',
'mail_from_address' => 'REDACTED',
'mail_domain' => 'REDACTED',
'mail_smtpauthtype' => 'REDACTED',
'mail_smtpauth' => 1,
'mail_smtphost' => 'REDACTED',
'mail_smtpport' => 'REDACTED',
'mail_smtpname' => 'REDACTED',
'mail_smtppassword' => 'REDACTED',
'maintenance' => false,
'log_type' => 'file',
'logfile' => '/var/log/nextcloud/nextcloud.log',
'logdateformat' => 'F d, Y H:i:s',
'logtimezone' => 'REDACTED',
'has_rebuilt_cache' => true,
'memcache.locking' => '\\OC\\Memcache\\Redis',
'memcache.local' => '\\OC\\Memcache\\APCu',
'memcache.distributed' => '\\OC\\Memcache\\Redis',
'redis' =>
array (
'host' => '/var/run/redis/redis-server.sock',
'port' => 0,
'dbindex' => 0,
'timeout' => 1.5,
'password' => 'REDACTED',
),
'theme' => '',
'default_phone_region' => 'REDACTED',
'updater.release.channel' => 'stable',
'instanceid' => 'REDACTED',
'allow_local_remote_servers' => true,
'app_install_overwrite' =>
array (
0 => 'apporder',
1 => 'keeweb',
2 => 'ocsms',
3 => 'contacts',
4 => 'maps',
5 => 'drawio',
6 => 'ocr',
7 => 'carnet',
8 => 'cookbook',
9 => 'music',
10 => 'side_menu',
11 => 'files_texteditor',
12 => 'bookmarks',
13 => 'breezedark',
14 => 'files_markdown',
15 => 'workflow_media_converter',
16 => 'end_to_end_encryption',
17 => 'richdocumentscode',
18 => 'epubreader',
19 => 'video_converter',
20 => 'memories',
21 => 'news',
),
'data-fingerprint' => 'REDACTED',
'memories.exiftool' => '/var/www/nextcloud/apps/memories/exiftool-bin/exiftool-amd64-glibc',
'memories.gis_type' => 2,
'loglevel' => 2,
'memories.vod.ffmpeg' => '/usr/bin/ffmpeg',
'memories.vod.ffprobe' => '/usr/bin/ffprobe',
'memories.vod.path' => '/var/www/nextcloud/apps/memories/exiftool-bin/go-vod-amd64',
'memories.vod.disable' => false,
'memories.vod.tempdir' => '/tmp',
);
The output of your Apache/nginx/system log in /var/log/____:
Nothing triggered by event
Here is my webserver configuration
upstream php-handler {
# server 127.0.0.1:9000;
server unix:/var/run/php/php8.2-fpm.sock;
}
# Set the `immutable` cache control options only for assets with a cache busting `v` argument
map $arg_v $asset_immutable {
"" "";
default "immutable";
}
server {
listen 80;
listen [::]:80;
server_name REDACTED;
# Prevent nginx HTTP Server Detection
server_tokens off;
# Enforce HTTPS
return 301 https://$server_name$request_uri;
}
server {
listen 127.0.0.2:443 quic reuseport; # QUIC
listen 127.0.0.2:443 ssl http2; # TCP
listen [::1]:443 quic reuseport; # QUIC
listen [::1]:443 ssl http2; # TCP
# listen 127.0.0.2:443 ssl http2; # TCP listener for HTTP/1.1
# listen [::1]:443 ssl http2;
server_name REDACTED;
# Path to the root of your installation
root /var/www/nextcloud/;
# Use Mozilla's guidelines for SSL/TLS settings
# https://mozilla.github.io/server-side-tls/ssl-config-generator/
ssl_certificate REDACTED;
ssl_certificate_key REDACTED;
# Prevent nginx HTTP Server Detection
server_tokens off;
# HSTS settings
# WARNING: Only add the preload option once you read about
# the consequences in https://hstspreload.org/. This option
# will add the domain to a hardcoded list that is shipped
# in all major browsers and getting removed from this list
# could take several months.
#add_header Strict-Transport-Security "max-age=15768000; includeSubDomains; preload" always;
# set max upload size and increase upload timeout:
client_max_body_size 512M;
client_body_timeout 300s;
fastcgi_buffers 64 4K;
# Enable gzip but do not remove ETag headers
gzip on;
gzip_vary on;
gzip_comp_level 4;
gzip_min_length 256;
gzip_proxied expired no-cache no-store private no_last_modified no_etag auth;
gzip_types application/atom+xml text/javascript application/javascript application/json application/ld+json application/manifest+json application/rss+xml application/vnd.geo+json application/vnd.ms-fontobject application/wasm application/x-font-ttf application/x-web-app-manifest+json application/xhtml+xml application/xml font/opentype image/bmp image/svg+xml image/x-icon text/cache-manifest text/css text/plain text/vcard text/vnd.rim.location.xloc text/vtt text/x-component text/x-cross-domain-policy;
# Pagespeed is not supported by Nextcloud, so if your server is built
# with the `ngx_pagespeed` module, uncomment this line to disable it.
#pagespeed off;
# The settings allows you to optimize the HTTP2 bandwitdth.
# See https://blog.cloudflare.com/delivering-http-2-upload-speed-improvements/
# for tunning hints
client_body_buffer_size 512k;
# HTTP response headers borrowed from Nextcloud `.htaccess`
add_header Referrer-Policy "no-referrer" always;
add_header X-Content-Type-Options "nosniff" always;
add_header X-Download-Options "noopen" always;
add_header X-Frame-Options "SAMEORIGIN" always;
add_header X-Permitted-Cross-Domain-Policies "none" always;
add_header X-Robots-Tag "noindex, nofollow" always;
add_header X-XSS-Protection "1; mode=block" always;
add_header Strict-Transport-Security "max-age=15768000; includeSubDomains; preload" always;
add_header Alt-Svc 'h3=":443"; ma=86400'; # Add Alt-Svc header to negotiate HTTP/3
# Remove X-Powered-By, which is an information leak
fastcgi_hide_header X-Powered-By;
# Add .mjs as a file extension for javascript
# Either include it in the default mime.types list
# or include you can include that list explicitly and add the file extension
# only for Nextcloud like below:
include mime.types;
types {
text/javascript js mjs;
}
# Specify how to handle directories -- specifying `/index.php$request_uri`
# here as the fallback means that Nginx always exhibits the desired behaviour
# when a client requests a path that corresponds to a directory that exists
# on the server. In particular, if that directory contains an index.php file,
# that file is correctly served; if it doesn't, then the request is passed to
# the front-end controller. This consistent behaviour means that we don't need
# to specify custom rules for certain paths (e.g. images and other assets,
# `/updater`, `/ocm-provider`, `/ocs-provider`), and thus
# `try_files $uri $uri/ /index.php$request_uri`
# always provides the desired behaviour.
index index.php index.html /index.php$request_uri;
# Enable QUIC and HTTP/3
quic_retry on;
quic_gso on;
ssl_early_data on;
# Rule borrowed from `.htaccess` to handle Microsoft DAV clients
location = / {
if ( $http_user_agent ~ ^DavClnt ) {
return 302 /remote.php/webdav/$is_args$args;
}
}
location = /robots.txt {
allow all;
log_not_found off;
access_log off;
}
# Make a regex exception for `/.well-known` so that clients can still
# access it despite the existence of the regex rule
# `location ~ /(\.|autotest|...)` which would otherwise handle requests
# for `/.well-known`.
location ^~ /.well-known {
# The rules in this block are an adaptation of the rules
# in `.htaccess` that concern `/.well-known`.
location = /.well-known/carddav { return 301 /remote.php/dav/; }
location = /.well-known/caldav { return 301 /remote.php/dav/; }
location /.well-known/acme-challenge { try_files $uri $uri/ =404; }
location /.well-known/pki-validation { try_files $uri $uri/ =404; }
# Let Nextcloud's API for `/.well-known` URIs handle all other
# requests by passing them to the front-end controller.
return 301 /index.php$request_uri;
}
# Rules borrowed from `.htaccess` to hide certain paths from clients
location ~ ^/(?:build|tests|config|lib|3rdparty|templates|data)(?:$|/) { return 404; }
location ~ ^/(?:\.|autotest|occ|issue|indie|db_|console) { return 404; }
# Ensure this block, which passes PHP files to the PHP process, is above the blocks
# which handle static assets (as seen below). If this block is not declared first,
# then Nginx will encounter an infinite rewriting loop when it prepends `/index.php`
# to the URI, resulting in a HTTP 500 error response.
location ~ \.php(?:$|/) {
# Required for legacy support
rewrite ^/(?!index|remote|public|cron|core\/ajax\/update|status|ocs\/v[12]|updater\/.+|oc[ms]-provider\/.+|.+\/richdocumentscode\/proxy) /index.php$request_uri;
fastcgi_split_path_info ^(.+?\.php)(/.*)$;
set $path_info $fastcgi_path_info;
try_files $fastcgi_script_name =404;
include fastcgi_params;
fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
fastcgi_param PATH_INFO $path_info;
fastcgi_param HTTPS on;
fastcgi_param modHeadersAvailable true; # Avoid sending the security headers twice
fastcgi_param front_controller_active true; # Enable pretty urls
fastcgi_pass php-handler;
fastcgi_intercept_errors on;
fastcgi_request_buffering off;
fastcgi_max_temp_file_size 0;
}
# Serve static files
location ~ \.(?:css|js|svg|gif|png|jpg|ico|wasm|tflite|map)$ {
try_files $uri /index.php$request_uri;
add_header Cache-Control "public, max-age=15778463, $asset_immutable";
access_log off; # Optional: Don't log access to assets
location ~ \.wasm$ {
default_type application/wasm;
}
}
location ~ \.woff2?$ {
try_files $uri /index.php$request_uri;
expires 7d; # Cache-Control policy borrowed from `.htaccess`
access_log off; # Optional: Don't log access to assets
}
# Rule borrowed from `.htaccess`
location /remote {
return 301 /remote.php$request_uri;
}
location / {
try_files $uri $uri/ /index.php$request_uri;
}
location ^~ /push/ {
proxy_pass http://127.0.0.1:7867/;
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection "Upgrade";
proxy_set_header Host $host;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
}
limit_req zone=one burst=200 nodelay;
}
Thank you!