How do you fix Nginx automatically 301 redirecting to the same URL with a trailing slash?

Question

I am getting an undesired behaviour from Nginx where it is rerouteing requests when I try to access index files within subdirectories of my web application to the same URL, but with an appended slash.

I have a simple web application set up with a root directory, and a number of subdirectories within it, each with a index.php file within them. The server's OS is Ubuntu server, Nginx is the server, and PHP5-fpm is installed.

I want to navigate to http://foo/bar to get the output of the index.php within bar. But if I navigate to http://foo/bar I am always redirected to http://foo/bar/.

I have looked at the Nginx access log in /var/log/nginx/access.log and it seems the requests are being redirected from what I am requesting (http://XXX.XXX.X.X/about for instance) to the same URL with an added slash (http://XXX.XXX.X.X/about/) via 301. Here is an example of the code from the log:

192.168.1.2 - - [06/May/2015:14:53:20 -0500] "GET /why HTTP/1.1" 301 178 "http://192.168.1.7/services/" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:37.0) Gecko/20100101 Firefox/37.0" 192.168.1.2 - - [06/May/2015:14:53:20 -0500] "GET /why/ HTTP/1.1" 200 3086 "http://192.168.1.7/services/" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:37.0) Gecko/20100101 Firefox/37.0" 192.168.1.2 - - [06/May/2015:14:53:20 -0500] "GET /contact HTTP/1.1" 301 178 "http://192.168.1.7/why/" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:37.0) Gecko/20100101 Firefox/37.0" 192.168.1.2 - - [06/May/2015:14:53:20 -0500] "GET /contact/ HTTP/1.1" 200 2325 "http://192.168.1.7/why/" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:37.0) Gecko/20100101 Firefox/37.0"

But I am not sure why they are being redirected or what is causing it.

These are the Nginx configuration files:

---

nginx.conf

user  nginx;
worker_processes  1;

pid /run/nginx.pid;

events {
        worker_connections 1024;
        # multi_accept on;
}

http {
        sendfile on;
        tcp_nopush on;
        tcp_nodelay on;
        keepalive_timeout 65;
        types_hash_max_size 2048;
        server_tokens off;

        include /etc/nginx/mime.types;
        default_type application/octet-stream;

        access_log /var/log/nginx/access.log;
        error_log /var/log/nginx/error.log;

        gzip on;
        gzip_disable "msie6";

        # gzip_vary on;
        # gzip_proxied any;
        # gzip_comp_level 6;
        # gzip_buffers 16 8k;
        # gzip_http_version 1.1;
        # gzip_types text/plain text/css application/json application/javascript text/xml application/xml application/xml+rss text/javascript;

        include /etc/nginx/sites-enabled/*;
}

sites-enabled default

server {
        listen 80 default_server;
        listen [::]:80 default_server;

        root /var/www/html/;

        index index.php index.html index.htm;

        server_name localhost;

        location / {
                try_files $uri $uri/ =404;
        }
        error_page 500 502 503 504 /50x.html;
        location = /50x.html {
            root /var/www/html/;
        }

        location ^~ /files/  {
          root /var/www/html/;
        }

        location ~ \.php$ {
            try_files $uri =404;
            fastcgi_split_path_info ^(.+\.php)(/.+)$;
            fastcgi_pass unix:/var/run/php5-fpm.sock;
            fastcgi_index index.php;
            fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
            include fastcgi_params;
        }
}

Why is Nginx doing this and what is(are) the solution(s) to this? What is the most "clean", "correct", or the solution most true to convention?

Answer 1

This is a result of the try_files directive. It's looking for the file named about, and when it fails to find it, it proceeds to look for a folder named about. (The folder is indicated by the trailing / on $uri/.)

The folder about/ matched, so nginx will then look for a file matching any of the names specified in the index directive. However, using an index file causes an internal redirect (quoted from the nginx docs), which is where your trailing / comes from.

For what it's worth, I see the exact same behavior on my nginx install, so it's not (just) your config.