demo-server.conf

server.conf

proxy_cache_path /tmp/nginx/cache levels=1:2 keys_zone=remoteimages:10m max_size=1g inactive=45m;

server {
    listen 80;
    listen [::]:80 ipv6only=on;

    listen 443 ssl;
    listen [::]:443 ipv6only=on ssl;

    ssl_certificate                  /etc/nginx/ssl/placeholder-fullchain.crt;
    ssl_certificate_key              /etc/nginx/ssl/placeholder-privkey.key;

    set $width -;
    set $height -;
    set $rotate 0;
    set $quality 96; # default to best quality in case image previously optimized
    set $sharpen 0;
    set $debugkey "empty";
    set $myhost "";
    set $ofmt "";
    set $debugcode "";

# image_filter_crop_offset {left,center,right} {top,center,bottom};
    set $crop_offx left;
    set $crop_offy top;

    server_name                      _;
    root                             /usr/share/nginx/html;
    index                            index.html index.htm;

# error should simply return as error so user can use image onerror handler
#    error_page                       403 = @403;
#    error_page                       404 = @404;
#    error_page                       415 = @415;
#    error_page                       500 = @500;
#    error_page                       502 503 504 = @empty;
    error_page                       301 302 307 = @handle_redirect;

# begin image_filter stuff
    resolver                         8.8.8.8 8.8.4.4;
    image_filter_buffer              20M;
    image_filter_interlace           on;

# needed to allow uri protocol slashes from being merged
    merge_slashes                    off;


#    proxy_redirect                   off;
    proxy_set_header                 X-Real-IP       $remote_addr;
    proxy_set_header                 X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header                 User-Agent      "$http_user_agent";

    proxy_connect_timeout            30s;
    proxy_send_timeout               30s;
    proxy_read_timeout               30s;
    proxy_temp_path                  /var/cache/nginx/temp;


# prevent client headers from going to origin
    proxy_pass_request_headers       off;

    proxy_ignore_headers             Vary Expires Set-Cookie Cache-Control;
    proxy_pass_header                P3P;
    proxy_cache_min_uses             2;
    proxy_cache                      remoteimages;
    proxy_ssl_server_name            on;
    proxy_intercept_errors           on;
    proxy_cache_use_stale            updating error timeout http_500 http_502 http_503 http_504;
    proxy_cache_background_update    on;

# valid for "any" http status within 10 minutes
    proxy_cache_valid                any 10m;
    proxy_cache_valid                301 302 307 0s;
    proxy_cache_key                  $request_uri;

# only allow GET method
    proxy_method                     GET;

    location /healthcheck {
        default_type                 text/plain;
        return 200 "OK";
    }

    location ~* ^/rx/([^\/]+)/(.*) {
        set $myargs                  "$1";
        set $protocol                "http";
        set $image_uri               "$2";
        set $cmd                     "resize";
        set $image_path              "";
        set $clean_uri               "";


# if no protocol in URL, add them
        if ($image_uri !~ "(http:|https:)") {
            set $image_uri "http://$image_uri";
        }

# now process the real image url
        if ($image_uri ~ "^(http|https)+([:\/]+)([^/]*)(.*)") {
            set $protocol $1;
            set $myhost $3;
            set $image_path $4;
            set $image_uri "$protocol://$myhost$image_path";
        }



# change this to whitelist your host       
#        if ($myhost !~ ".*(host1.com|host2.org|host3.edu|host4.net|host5.info)$") {
#            set $image_uri "";
#            set $debugkey "$myhost=denied";
#            return 403;
#            break;
#        }




# width
        if ($myargs ~ "^(\d+)\D*") {
            set $width $1;
        }

        if ($myargs ~ "w([_]*)(\d+)") {
            set $width $2;
        }

        if ($arg_w) {
            set $width $arg_w;
        }

# height
        if ($myargs ~ "x(\d+)") {
            set $height $1;
        }

        if ($myargs ~ "h([_]*)(\d+)") {
            set $height $2;
        }

        if ($arg_h) {
            set $height $arg_h;
        }

# quality
        if ($myargs ~ "q([_]*)(\d+)") {
            set $quality $2;
        }

        if ($arg_q) {
            set $quality $arg_q;
        }

# rotate
        if ($myargs ~ "r([_]*)(\d+)") {
            set $rotate $2;
        }

        if ($arg_r) {
            set $rotate $arg_r;
        }

# gravity
        if ($myargs ~ "Center") {
            set $crop_offx center;
            set $crop_offy center;
        }

        if ($arg_g ~ "Center") {
            set $crop_offx center;
            set $crop_offy center;
        }

        if ($myargs ~ "South") {
            set $crop_offy bottom;
        }

        if ($arg_g ~ "South") {
            set $crop_offy bottom;
        }

        if ($myargs ~ "East") {
            set $crop_offx right;
        }

        if ($arg_g ~ "East") {
            set $crop_offx right;
        }

# sharpen
        if ($myargs ~ "e([_]*)(\d+)") {
            set $sharpen $2;
        }

        if ($arg_e) {
            set $sharpen $arg_e;
        }

# output format
        if ($myargs ~ "ofmt([_]*)(\w+)") {
            set $ofmt $2;
        }

        if ($arg_ofmt) {
            set $ofmt $arg_ofmt;
        }

# crop
        if ($myargs ~ "c([_]*)1") {
            set $cmd "crop";
        }

        if ($arg_c = "1") {
            set $cmd "crop";
        }

        if ($myargs ~ "g_+") {
            set $cmd "crop";
        }

        if ($arg_g) {
            set $cmd "crop";
        }

# watermark
        if ($myargs ~ "water([_]*)1") {
            set $cmd "water";
        }

        set $debugkey "$image_uri?w=$width&h=$height&q=$quality&r=$rotate&e=$sharpen&cmd=$cmd&ofmt=$ofmt";

        set_unescape_uri            $clean_uri "$image_uri$is_args$args";
        rewrite ^ /cmd/$cmd last;
    }

    location /cmd/resize {
        internal;

        proxy_pass                  $clean_uri;
        include                     /etc/nginx/sites-enabled/proxy-hide-headers.common;

        add_header                  X-ImageProxy-Cache $upstream_cache_status;
        add_header                  X-ImageProxy-Debug $debugkey;
        expires                     24h;
        add_header                  Cache-Control "public";
        
        #image_filter_water_image  /app/logo.png;
        #image_filter_water_pos    center;
        image_filter_scale_max      3;
        
        image_filter_sharpen        $sharpen;
        image_filter_jpeg_quality   $quality;
        image_filter_webp_quality   $quality;
        image_filter_output         $ofmt;
        image_filter                rotate $rotate;

        # image_filter                resize $width $height;
        image_filter                resize $width $height;
    }

    location /cmd/water {
        internal;

        proxy_pass                  $clean_uri;
        include                     /etc/nginx/sites-enabled/proxy-hide-headers.common;

        add_header                  X-ImageProxy-Cache $upstream_cache_status;
        add_header                  X-ImageProxy-Debug $debugkey;
        expires                     24h;
        add_header                  Cache-Control "public";
        
        image_filter_water_image    /app/logo.png;
        #image_filter_water_pos    center;
        image_filter_scale_max      3;
        
        image_filter_sharpen        $sharpen;
        image_filter_jpeg_quality   $quality;
        image_filter_webp_quality   $quality;
        image_filter_output         $ofmt;
        image_filter                rotate $rotate;

        image_filter                resize $width $height;
    }

    location /cmd/crop {
        internal;

        proxy_pass                  $clean_uri;
        include                     /etc/nginx/sites-enabled/proxy-hide-headers.common;

        add_header                  X-ImageProxy-Cache $upstream_cache_status;
        add_header                  X-ImageProxy-Debug $debugkey;
        expires                     24h;
        add_header                  Cache-Control "public";
        
        #image_filter_water_image  /app/logo.png;
        #image_filter_water_pos    center;
        image_filter_scale_max      3;
        
        image_filter_sharpen        $sharpen;
        image_filter_jpeg_quality   $quality;
        image_filter_webp_quality   $quality;
        image_filter_output         $ofmt;
        image_filter                rotate $rotate;

        image_filter_crop_offset    $crop_offx $crop_offy;
        image_filter                crop $width $height;
    }

    location @handle_redirect {
        set                         $image_uri "$upstream_http_location";
 
# if relative url, append base path
        if ($image_uri !~ "(http:|https:)") {
            set $image_uri "$protocol://$myhost$image_uri";
        }

        set_unescape_uri            $clean_uri "http://127.0.0.1/rx/$myargs/$image_uri";
        proxy_cache_bypass          1;
        proxy_pass                  $clean_uri;
    }

    location @403 {
        add_header                  X-ImageProxy-Code 403 always;
        add_header                  X-ImageProxy-Debug $debugkey always;
        empty_gif;
    }

    location @404 {
        add_header                  X-ImageProxy-Code 404 always;
        add_header                  X-ImageProxy-Debug $debugkey always;
        empty_gif;
    }

    location @415 {
        add_header                  X-ImageProxy-Code 415 always;
        add_header                  X-ImageProxy-Debug $debugkey always;
        empty_gif;
    }

    location @500 {
        add_header                  X-ImageProxy-Code 500 always;
        add_header                  X-ImageProxy-Debug $debugkey always;
        empty_gif;
    }

    location @empty {
        add_header                  X-ImageProxy-Debug $debugkey always;
        empty_gif;
    }
}