Remove unnecessary nginx redirect rule from reverse proxy documentation

[scottlimmer]

Remove redirect rule for flower config as per https://airflow.apache.org/docs/apache-airflow/stable/security/flower.html#flower-url-prefix

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[scottlimmer]

@dirrao @potiuk Can we get a re-review on this so it doesn't get squashed by the bot? I believe comments have been addressed.

[potiuk]

But - is it correct ? I thought it was supposed to be differently for flower. Did you test it?

[scottlimmer]

But - is it correct ? I thought it was supposed to be differently for flower. Did you test it?

This change is reflective of the current configuration I have in production.

When the rewrite ^/myorg/flower/(.*)$ /$1 break; # remove prefix from http header line is present in the config, any requests to /myorg/flower/ result in a 404.

Also, that line was introduced 7 years ago with no more info than the line comment, so it is difficult to determine exactly what issue it was resolving.

For reference below is my full nginx.conf for a NGINX proxy / SSL offload in an Airflow docker deployment where flower is operating from a subdirectory on an airflow subdomain.

server {
    listen                      80;
    server_name                 _;
    return 301 https://$host$request_uri;
}

server {
    listen                      443 ssl;
    server_name                 airflow.example.org;

    ssl_certificate             /etc/ssl/certs/airflow.crt;
    ssl_certificate_key         /etc/ssl/private/airflow.key;

    location / {
        proxy_pass              http://airflow-webserver:8080;
        proxy_set_header        Host $http_host;
        proxy_redirect          off;
        proxy_http_version      1.1;
        proxy_set_header        Upgrade $http_upgrade;
        proxy_set_header        Connection "upgrade";
        proxy_set_header        X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header        X-Forwarded-Proto $scheme;
        proxy_set_header        X-Real-IP $remote_addr;
    }

    location /flower/ {
        auth_basic              "Airflow Flower";
        auth_basic_user_file    "/etc/nginx/.htpasswd";
        proxy_pass              http://flower:5555;
        proxy_set_header        Host $http_host;
        proxy_redirect          off;
        proxy_http_version      1.1;
        proxy_set_header        Upgrade $http_upgrade;
        proxy_set_header        Connection "upgrade";
        proxy_set_header        X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header        X-Forwarded-Proto $scheme;
        proxy_set_header        X-Real-IP $remote_addr;
    }
}

[boring-cyborg]

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