{{ $all := . }}
{{ $servers := .Servers }}
{{ $cfg := .Cfg }}
{{ $IsIPV6Enabled := .IsIPV6Enabled }}
{{ $healthzURI := .HealthzURI }}
{{ $backends := .Backends }}
{{ $proxyHeaders := .ProxySetHeaders }}
{{ $addHeaders := .AddHeaders }}

{{ if $cfg.EnableModsecurity }}
load_module /etc/nginx/modules/ngx_http_modsecurity_module.so;
{{ end }}

{{ if $cfg.EnableOpentracing }}
load_module /etc/nginx/modules/ngx_http_opentracing_module.so;
{{ end }}

{{ if (and $cfg.EnableOpentracing (ne $cfg.ZipkinCollectorHost "")) }}
load_module /etc/nginx/modules/ngx_http_zipkin_module.so;
{{ end }}

daemon off;

worker_processes {{ $cfg.WorkerProcesses }};
pid /run/nginx.pid;
{{ if ne .MaxOpenFiles 0 }}
worker_rlimit_nofile {{ .MaxOpenFiles }};
{{ end}}

{{/* http://nginx.org/en/docs/ngx_core_module.html#worker_shutdown_timeout */}}
{{/* avoid waiting too long during a reload */}}
worker_shutdown_timeout {{ $cfg.WorkerShutdownTimeout }} ;

events {
    multi_accept        on;
    worker_connections  {{ $cfg.MaxWorkerConnections }};
    use                 epoll;
}

http {
    {{/* we use the value of the header X-Forwarded-For to be able to use the geo_ip module */}}
    {{ if $cfg.UseProxyProtocol }}
    real_ip_header      proxy_protocol;
    {{ else }}
    real_ip_header      {{ $cfg.ForwardedForHeader }};
    {{ end }}

    real_ip_recursive   on;
    {{ range $trusted_ip := $cfg.ProxyRealIPCIDR }}
    set_real_ip_from    {{ $trusted_ip }};
    {{ end }}

    {{/* databases used to determine the country depending on the client IP address */}}
    {{/* http://nginx.org/en/docs/http/ngx_http_geoip_module.html */}}
    {{/* this is require to calculate traffic for individual country using GeoIP in the status page */}}
    geoip_country       /etc/nginx/GeoIP.dat;
    geoip_city          /etc/nginx/GeoLiteCity.dat;
    geoip_proxy_recursive on;

    {{ if $cfg.EnableVtsStatus }}
    vhost_traffic_status_zone shared:vhost_traffic_status:{{ $cfg.VtsStatusZoneSize }};
    vhost_traffic_status_filter_by_set_key {{ $cfg.VtsDefaultFilterKey }};
    {{ end }}

    sendfile            on;

    aio                 threads;
    aio_write           on;

    tcp_nopush          on;
    tcp_nodelay         on;

    log_subrequest      on;

    reset_timedout_connection on;

    keepalive_timeout  {{ $cfg.KeepAlive }}s;
    keepalive_requests {{ $cfg.KeepAliveRequests }};

    client_header_buffer_size       {{ $cfg.ClientHeaderBufferSize }};
    client_header_timeout           {{ $cfg.ClientHeaderTimeout }}s;
    large_client_header_buffers     {{ $cfg.LargeClientHeaderBuffers }};
    client_body_buffer_size         {{ $cfg.ClientBodyBufferSize }};
    client_body_timeout             {{ $cfg.ClientBodyTimeout }}s;

    http2_max_field_size            {{ $cfg.HTTP2MaxFieldSize }};
    http2_max_header_size           {{ $cfg.HTTP2MaxHeaderSize }};

    types_hash_max_size             2048;
    server_names_hash_max_size      {{ $cfg.ServerNameHashMaxSize }};
    server_names_hash_bucket_size   {{ $cfg.ServerNameHashBucketSize }};
    map_hash_bucket_size            {{ $cfg.MapHashBucketSize }};

    proxy_headers_hash_max_size     {{ $cfg.ProxyHeadersHashMaxSize }};
    proxy_headers_hash_bucket_size  {{ $cfg.ProxyHeadersHashBucketSize }};

    variables_hash_bucket_size      {{ $cfg.VariablesHashBucketSize }};
    variables_hash_max_size         {{ $cfg.VariablesHashMaxSize }};

    underscores_in_headers          {{ if $cfg.EnableUnderscoresInHeaders }}on{{ else }}off{{ end }};
    ignore_invalid_headers          {{ if $cfg.IgnoreInvalidHeaders }}on{{ else }}off{{ end }};

    {{ if $cfg.EnableOpentracing }}
    opentracing on;
    {{ end }}

    {{ if (and $cfg.EnableOpentracing (ne $cfg.ZipkinCollectorHost "")) }}
    zipkin_collector_host           {{ $cfg.ZipkinCollectorHost }};
    zipkin_collector_port           {{ $cfg.ZipkinCollectorPort }};
    zipkin_service_name             {{ $cfg.ZipkinServiceName }};
    {{ end }}

    include /etc/nginx/mime.types;
    default_type text/html;

    {{ if $cfg.EnableBrotli }}
    brotli on;
    brotli_comp_level {{ $cfg.BrotliLevel }};
    brotli_types {{ $cfg.BrotliTypes }};
    {{ end }}

    {{ if $cfg.UseGzip }}
    gzip on;
    gzip_comp_level 5;
    gzip_http_version 1.1;
    gzip_min_length 256;
    gzip_types {{ $cfg.GzipTypes }};
    gzip_proxied any;
    gzip_vary on;
    {{ end }}

    # Custom headers for response
    {{ range $k, $v := $addHeaders }}
    add_header {{ $k }}            "{{ $v }}";
    {{ end }}

    server_tokens {{ if $cfg.ShowServerTokens }}on{{ else }}off{{ end }};

    # disable warnings
    uninitialized_variable_warn off;

    # Additional available variables:
    # $namespace
    # $ingress_name
    # $service_name
    log_format upstreaminfo {{ if $cfg.LogFormatEscapeJSON }}escape=json {{ end }}'{{ buildLogFormatUpstream $cfg }}';

    {{/* map urls that should not appear in access.log */}}
    {{/* http://nginx.org/en/docs/http/ngx_http_log_module.html#access_log */}}
    map $request_uri $loggable {
        {{ range $reqUri := $cfg.SkipAccessLogURLs }}
        {{ $reqUri }} 0;{{ end }}
        default 1;
    }

    {{ if $cfg.DisableAccessLog }}
    access_log off;
    {{ else }}
    access_log {{ $cfg.AccessLogPath }} upstreaminfo if=$loggable;
    {{ end }}
    error_log  {{ $cfg.ErrorLogPath }} {{ $cfg.ErrorLogLevel }};

    {{ buildResolvers $cfg.Resolver }}

    {{/* Whenever nginx proxies a request without a "Connection" header, the "Connection" header is set to "close" */}}
    {{/* when making the target request.  This means that you cannot simply use */}}
    {{/* "proxy_set_header Connection $http_connection" for WebSocket support because in this case, the */}}
    {{/* "Connection" header would be set to "" whenever the original request did not have a "Connection" header, */}}
    {{/* which would mean no "Connection" header would be in the target request.  Since this would deviate from */}}
    {{/* normal nginx behavior we have to use this approach. */}}
    # Retain the default nginx handling of requests without a "Connection" header
    map $http_upgrade $connection_upgrade {
        default          upgrade;
        ''               close;
    }

    map {{ buildForwardedFor $cfg.ForwardedForHeader }} $the_real_ip {
    {{ if $cfg.UseProxyProtocol }}
        # Get IP address from Proxy Protocol
        default          $proxy_protocol_addr;
    {{ else }}
        default          $remote_addr;
    {{ end }}
    }

    # trust http_x_forwarded_proto headers correctly indicate ssl offloading
    map $http_x_forwarded_proto $pass_access_scheme {
        default          $http_x_forwarded_proto;
        ''               $scheme;
    }

    map $http_x_forwarded_port $pass_server_port {
        default           $http_x_forwarded_port;
        ''                $server_port;
    }

    map $http_x_forwarded_host $best_http_host {
        default          $http_x_forwarded_host;
        ''               $this_host;
    }

    {{ if $all.IsSSLPassthroughEnabled }}
    # map port {{ $all.ListenPorts.SSLProxy }} to 443 for header X-Forwarded-Port
    map $pass_server_port $pass_port {
        {{ $all.ListenPorts.SSLProxy }}              443;
        default          $pass_server_port;
    }
    {{ else }}
    map $pass_server_port $pass_port {
        443              443;
        default          $pass_server_port;
    }
    {{ end }}

    # Obtain best http host
    map $http_host $this_host {
        default          $http_host;
        ''               $host;
    }

    {{ if $cfg.ComputeFullForwardedFor }}
    # We can't use $proxy_add_x_forwarded_for because the realip module
    # replaces the remote_addr too soon
    map $http_x_forwarded_for $full_x_forwarded_for {
        {{ if $all.Cfg.UseProxyProtocol }}
        default          "$http_x_forwarded_for, $proxy_protocol_addr";
        ''               "$proxy_protocol_addr";
        {{ else }}
        default          "$http_x_forwarded_for, $realip_remote_addr";
        ''               "$realip_remote_addr";
        {{ end}}
    }
    {{ end }}

    server_name_in_redirect off;
    port_in_redirect        off;

    ssl_protocols {{ $cfg.SSLProtocols }};

    # turn on session caching to drastically improve performance
    {{ if $cfg.SSLSessionCache }}
    ssl_session_cache builtin:1000 shared:SSL:{{ $cfg.SSLSessionCacheSize }};
    ssl_session_timeout {{ $cfg.SSLSessionTimeout }};
    {{ end }}

    # allow configuring ssl session tickets
    ssl_session_tickets {{ if $cfg.SSLSessionTickets }}on{{ else }}off{{ end }};

    {{ if not (empty $cfg.SSLSessionTicketKey ) }}
    ssl_session_ticket_key /etc/nginx/tickets.key;
    {{ end }}

    # slightly reduce the time-to-first-byte
    ssl_buffer_size {{ $cfg.SSLBufferSize }};

    {{ if not (empty $cfg.SSLCiphers) }}
    # allow configuring custom ssl ciphers
    ssl_ciphers '{{ $cfg.SSLCiphers }}';
    ssl_prefer_server_ciphers on;
    {{ end }}

    {{ if not (empty $cfg.SSLDHParam) }}
    # allow custom DH file http://nginx.org/en/docs/http/ngx_http_ssl_module.html#ssl_dhparam
    ssl_dhparam {{ $cfg.SSLDHParam }};
    {{ end }}

    {{ if not $cfg.EnableDynamicTLSRecords }}
    ssl_dyn_rec_size_lo 0;
    {{ end }}

    ssl_ecdh_curve {{ $cfg.SSLECDHCurve }};

    {{ if .CustomErrors }}
    # Custom error pages
    proxy_intercept_errors on;
    {{ end }}

    {{ range $errCode := $cfg.CustomHTTPErrors }}
    error_page {{ $errCode }} = @custom_{{ $errCode }};{{ end }}

    proxy_ssl_session_reuse on;

    {{ if $cfg.AllowBackendServerHeader }}
    proxy_pass_header Server;
    {{ end }}

    {{ if not (empty $cfg.HTTPSnippet) }}
    # Custom code snippet configured in the configuration configmap
    {{ $cfg.HTTPSnippet }}
    {{ end }}

    {{ range $name, $upstream := $backends }}
    {{ if eq $upstream.SessionAffinity.AffinityType "cookie" }}
    upstream sticky-{{ $upstream.Name }} {
        sticky hash={{ $upstream.SessionAffinity.CookieSessionAffinity.Hash }} name={{ $upstream.SessionAffinity.CookieSessionAffinity.Name }}  httponly;

        {{ if (gt $cfg.UpstreamKeepaliveConnections 0) }}
        keepalive {{ $cfg.UpstreamKeepaliveConnections }};
        {{ end }}

        {{ range $server := $upstream.Endpoints }}server {{ $server.Address | formatIP }}:{{ $server.Port }} max_fails={{ $server.MaxFails }} fail_timeout={{ $server.FailTimeout }};
        {{ end }}

    }

    {{ end }}


    upstream {{ $upstream.Name }} {
        # Load balance algorithm; empty for round robin, which is the default
        {{ if ne $cfg.LoadBalanceAlgorithm "round_robin" }}
        {{ $cfg.LoadBalanceAlgorithm }};
        {{ end }}

        {{ if $upstream.UpstreamHashBy }}
        hash {{ $upstream.UpstreamHashBy }} consistent;
        {{ end }}

        {{ if (gt $cfg.UpstreamKeepaliveConnections 0) }}
        keepalive {{ $cfg.UpstreamKeepaliveConnections }};
        {{ end }}

        {{ range $server := $upstream.Endpoints }}server {{ $server.Address | formatIP }}:{{ $server.Port }} max_fails={{ $server.MaxFails }} fail_timeout={{ $server.FailTimeout }};
        {{ end }}
    }

    {{ end }}

    {{/* build the maps that will be use to validate the Whitelist */}}
    {{ range $index, $server := $servers }}
    {{ range $location := $server.Locations }}
    {{ $path := buildLocation $location }}

    {{ if isLocationAllowed $location }}
    {{ if gt (len $location.Whitelist.CIDR) 0 }}

    # Deny for {{ print $server.Hostname  $path }}
    geo $the_real_ip {{ buildDenyVariable (print $server.Hostname "_"  $path) }} {
        default 1;

        {{ range $ip := $location.Whitelist.CIDR }}
        {{ $ip }} 0;{{ end }}
    }
    {{ end }}
    {{ end }}
    {{ end }}
    {{ end }}

    {{ range $rl := (filterRateLimits $servers ) }}
    # Ratelimit {{ $rl.Name }}
    geo $the_real_ip $whitelist_{{ $rl.ID }} {
        default 0;
        {{ range $ip := $rl.Whitelist }}
        {{ $ip }} 1;{{ end }}
    }

    # Ratelimit {{ $rl.Name }}
    map $whitelist_{{ $rl.ID }} $limit_{{ $rl.ID }} {
        0 {{ $cfg.LimitConnZoneVariable }};
        1 "";
    }
    {{ end }}

    {{/* build all the required rate limit zones. Each annotation requires a dedicated zone */}}
    {{/* 1MB -> 16 thousand 64-byte states or about 8 thousand 128-byte states */}}
    {{ range $zone := (buildRateLimitZones $servers) }}
    {{ $zone }}
    {{ end }}

    {{/* Build server redirects (from/to www) */}}
    {{ range $hostname, $to := .RedirectServers }}
    server {
        {{ range $address := $all.Cfg.BindAddressIpv4 }}
        listen {{ $address }}:{{ $all.ListenPorts.HTTP }}{{ if $all.Cfg.UseProxyProtocol }} proxy_protocol{{ end }};
        listen {{ $address }}:{{ if $all.IsSSLPassthroughEnabled }}{{ $all.ListenPorts.SSLProxy }} proxy_protocol{{ else }}{{ $all.ListenPorts.HTTPS }}{{ if $all.Cfg.UseProxyProtocol }} proxy_protocol{{ end }}{{ end }} ssl;
        {{ else }}
        listen {{ $all.ListenPorts.HTTP }}{{ if $all.Cfg.UseProxyProtocol }} proxy_protocol{{ end }};
        listen {{ if $all.IsSSLPassthroughEnabled }}{{ $all.ListenPorts.SSLProxy }} proxy_protocol{{ else }}{{ $all.ListenPorts.HTTPS }}{{ if $all.Cfg.UseProxyProtocol }} proxy_protocol{{ end }}{{ end }} ssl;
        {{ end }}
        {{ if $IsIPV6Enabled }}
        {{ range $address := $all.Cfg.BindAddressIpv6 }}
        listen {{ $address }}:{{ $all.ListenPorts.HTTP }}{{ if $all.Cfg.UseProxyProtocol }} proxy_protocol{{ end }};
        listen {{ $address }}:{{ if $all.IsSSLPassthroughEnabled }}{{ $all.ListenPorts.SSLProxy }} proxy_protocol{{ else }}{{ $all.ListenPorts.HTTPS }}{{ if $all.Cfg.UseProxyProtocol }} proxy_protocol{{ end }}{{ end }};
        {{ else }}
        listen [::]:{{ $all.ListenPorts.HTTP }}{{ if $all.Cfg.UseProxyProtocol }} proxy_protocol{{ end }};
        listen [::]:{{ if $all.IsSSLPassthroughEnabled }}{{ $all.ListenPorts.SSLProxy }} proxy_protocol{{ else }}{{ $all.ListenPorts.HTTPS }}{{ if $all.Cfg.UseProxyProtocol }} proxy_protocol{{ end }}{{ end }};
        {{ end }}
        {{ end }}
        server_name {{ $hostname }};

        {{ if ne $all.ListenPorts.HTTPS 443 }}
        {{ $redirect_port := (printf ":%v" $all.ListenPorts.HTTPS) }}
        return {{ $all.Cfg.HTTPRedirectCode }} $scheme://{{ $to }}{{ $redirect_port }}$request_uri;
        {{ else }}
        return {{ $all.Cfg.HTTPRedirectCode }} $scheme://{{ $to }}$request_uri;
        {{ end }}
    }
    {{ end }}

    {{ range $index, $server := $servers }}

    ## start server {{ $server.Hostname }}
    server {
        server_name {{ $server.Hostname }} {{ $server.Alias }};
        {{ template "SERVER" serverConfig $all $server }}

        {{ if not (empty $cfg.ServerSnippet) }}
        # Custom code snippet configured in the configuration configmap
        {{ $cfg.ServerSnippet }}
        {{ end }}

        {{ template "CUSTOM_ERRORS" $all }}
    }
    ## end server {{ $server.Hostname }}

    {{ end }}

    # default server, used for NGINX healthcheck and access to nginx stats
    server {
        # Use the port {{ $all.ListenPorts.Status }} (random value just to avoid known ports) as default port for nginx.
        # Changing this value requires a change in:
        # https://github.com/kubernetes/ingress-nginx/blob/master/controllers/nginx/pkg/cmd/controller/nginx.go
        listen {{ $all.ListenPorts.Status }} default_server reuseport backlog={{ $all.BacklogSize }};
        {{ if $IsIPV6Enabled }}listen [::]:{{ $all.ListenPorts.Status }} default_server reuseport backlog={{ $all.BacklogSize }};{{ end }}
        set $proxy_upstream_name "-";

        location {{ $healthzURI }} {
            access_log off;
            return 200;
        }

        location /nginx_status {
            set $proxy_upstream_name "internal";

            {{ if $cfg.EnableVtsStatus }}
            vhost_traffic_status_display;
            vhost_traffic_status_display_format html;
            {{ else }}
            access_log off;
            stub_status on;
            {{ end }}
        }

        location / {
            {{ if .CustomErrors }}
            proxy_set_header    X-Code 404;
            {{ end }}
            set $proxy_upstream_name "upstream-default-backend";
            proxy_pass          http://upstream-default-backend;
        }

        {{ template "CUSTOM_ERRORS" $all }}
    }
}

stream {
    log_format log_stream {{ $cfg.LogFormatStream }};

    {{ if $cfg.DisableAccessLog }}
    access_log off;
    {{ else }}
    access_log {{ $cfg.AccessLogPath }} log_stream;
    {{ end }}

    error_log  {{ $cfg.ErrorLogPath }};

    # TCP services
    {{ range $i, $tcpServer := .TCPBackends }}
    upstream tcp-{{ $tcpServer.Port }}-{{ $tcpServer.Backend.Namespace }}-{{ $tcpServer.Backend.Name }}-{{ $tcpServer.Backend.Port }} {
        # NOTE(portdirect): mark the 1st server as up, the 2nd as backup, and all others as down.
        # The ingress controller will manage this list, based on the health checks in the backend pods,
        # which approximates the pattern commonly used by Haproxy's httpchk.
    {{ range $j, $endpoint := $tcpServer.Endpoints }}
    {{ if eq $j 0 }}
        # NOTE(portdirect): see https://docs.nginx.com/nginx/admin-guide/load-balancer/tcp-health-check/#passive-tcp-health-checks to tune passive healthchecks
        server                  {{ $endpoint.Address }}:{{ $endpoint.Port }};
    {{ else if eq $j 1 }}
        server                  {{ $endpoint.Address }}:{{ $endpoint.Port }} backup;
    {{ else }}
        server                  {{ $endpoint.Address }}:{{ $endpoint.Port }} down;
    {{ end }}
    {{ end }}
    }
    server {
        {{ range $address := $all.Cfg.BindAddressIpv4 }}
        listen                  {{ $address }}:{{ $tcpServer.Port }}{{ if $tcpServer.Backend.ProxyProtocol.Decode }} proxy_protocol{{ end }};
        {{ else }}
        listen                  {{ $tcpServer.Port }}{{ if $tcpServer.Backend.ProxyProtocol.Decode }} proxy_protocol{{ end }};
        {{ end }}
        {{ if $IsIPV6Enabled }}
        {{ range $address := $all.Cfg.BindAddressIpv6 }}
        listen                  {{ $address }}:{{ $tcpServer.Port }}{{ if $tcpServer.Backend.ProxyProtocol.Decode }} proxy_protocol{{ end }};
        {{ else }}
        listen                  [::]:{{ $tcpServer.Port }}{{ if $tcpServer.Backend.ProxyProtocol.Decode }} proxy_protocol{{ end }};
        {{ end }}
        {{ end }}
        proxy_timeout           {{ $cfg.ProxyStreamTimeout }};
        proxy_pass              tcp-{{ $tcpServer.Port }}-{{ $tcpServer.Backend.Namespace }}-{{ $tcpServer.Backend.Name }}-{{ $tcpServer.Backend.Port }};
        {{ if $tcpServer.Backend.ProxyProtocol.Encode }}
        proxy_protocol          on;
        {{ end }}
    }

    {{ end }}

    # UDP services
    {{ range $i, $udpServer := .UDPBackends }}
    upstream udp-{{ $udpServer.Port }}-{{ $udpServer.Backend.Namespace }}-{{ $udpServer.Backend.Name }}-{{ $udpServer.Backend.Port }} {
    {{ range $j, $endpoint := $udpServer.Endpoints }}
        server                  {{ $endpoint.Address }}:{{ $endpoint.Port }};
    {{ end }}
    }

    server {
        {{ range $address := $all.Cfg.BindAddressIpv4 }}
        listen                  {{ $address }}:{{ $udpServer.Port }} udp;
        {{ else }}
        listen                  {{ $udpServer.Port }} udp;
        {{ end }}
        {{ if $IsIPV6Enabled }}
        {{ range $address := $all.Cfg.BindAddressIpv6 }}
        listen                  {{ $address }}:{{ $udpServer.Port }} udp;
        {{ else }}
        listen                  [::]:{{ $udpServer.Port }} udp;
        {{ end }}
        {{ end }}
        proxy_responses         {{ $cfg.ProxyStreamResponses }};
        proxy_timeout           {{ $cfg.ProxyStreamTimeout }};
        proxy_pass              udp-{{ $udpServer.Port }}-{{ $udpServer.Backend.Namespace }}-{{ $udpServer.Backend.Name }}-{{ $udpServer.Backend.Port }};
    }

    {{ end }}
}

{{/* definition of templates to avoid repetitions */}}
{{ define "CUSTOM_ERRORS" }}
        {{ $proxySetHeaders := .ProxySetHeaders }}
        {{ range $errCode := .Cfg.CustomHTTPErrors }}
        location @custom_{{ $errCode }} {
            internal;

            proxy_intercept_errors off;

            proxy_set_header       X-Code             {{ $errCode }};
            proxy_set_header       X-Format           $http_accept;
            proxy_set_header       X-Original-URI     $request_uri;
            proxy_set_header       X-Namespace        $namespace;
            proxy_set_header       X-Ingress-Name     $ingress_name;
            proxy_set_header       X-Service-Name     $service_name;

            rewrite                (.*) / break;
            proxy_pass             http://upstream-default-backend;
        }
        {{ end }}
{{ end }}

{{/* CORS support from https://michielkalkman.com/snippets/nginx-cors-open-configuration.html */}}
{{ define "CORS" }}
     {{ $cors := .CorsConfig }}
     # Cors Preflight methods needs additional options and different Return Code
     if ($request_method = 'OPTIONS') {
        add_header 'Access-Control-Allow-Origin' '{{ $cors.CorsAllowOrigin }}' always;
        {{ if $cors.CorsAllowCredentials }} add_header 'Access-Control-Allow-Credentials' '{{ $cors.CorsAllowCredentials }}' always; {{ end }}
        add_header 'Access-Control-Allow-Methods' '{{ $cors.CorsAllowMethods }}' always;
        add_header 'Access-Control-Allow-Headers' '{{ $cors.CorsAllowHeaders }}' always;
        add_header 'Access-Control-Max-Age' 1728000;
        add_header 'Content-Type' 'text/plain charset=UTF-8';
        add_header 'Content-Length' 0;
        return 204;
     }

        add_header 'Access-Control-Allow-Origin' '{{ $cors.CorsAllowOrigin }}' always;
        {{ if $cors.CorsAllowCredentials }} add_header 'Access-Control-Allow-Credentials' '{{ $cors.CorsAllowCredentials }}' always; {{ end }}
        add_header 'Access-Control-Allow-Methods' '{{ $cors.CorsAllowMethods }}' always;
        add_header 'Access-Control-Allow-Headers' '{{ $cors.CorsAllowHeaders }}' always;

{{ end }}

{{/* definition of server-template to avoid repetitions with server-alias */}}
{{ define "SERVER" }}
        {{ $all := .First }}
        {{ $server := .Second }}
        {{ range $address := $all.Cfg.BindAddressIpv4 }}
        listen {{ $address }}:{{ $all.ListenPorts.HTTP }}{{ if $all.Cfg.UseProxyProtocol }} proxy_protocol{{ end }}{{ if eq $server.Hostname "_"}} default_server reuseport backlog={{ $all.BacklogSize }}{{end}};
        {{ else }}
        listen {{ $all.ListenPorts.HTTP }}{{ if $all.Cfg.UseProxyProtocol }} proxy_protocol{{ end }}{{ if eq $server.Hostname "_"}} default_server reuseport backlog={{ $all.BacklogSize }}{{end}};
        {{ end }}
        {{ if $all.IsIPV6Enabled }}
        {{ range $address := $all.Cfg.BindAddressIpv6 }}
        listen {{ $address }}:{{ $all.ListenPorts.HTTP }}{{ if $all.Cfg.UseProxyProtocol }} proxy_protocol{{ end }}{{ if eq $server.Hostname "_"}} default_server reuseport backlog={{ $all.BacklogSize }}{{ end }};
        {{ else }}
        listen [::]:{{ $all.ListenPorts.HTTP }}{{ if $all.Cfg.UseProxyProtocol }} proxy_protocol{{ end }}{{ if eq $server.Hostname "_"}} default_server reuseport backlog={{ $all.BacklogSize }}{{ end }};
        {{ end }}
        {{ end }}
        set $proxy_upstream_name "-";

        {{/* Listen on {{ $all.ListenPorts.SSLProxy }} because port {{ $all.ListenPorts.HTTPS }} is used in the TLS sni server */}}
        {{/* This listener must always have proxy_protocol enabled, because the SNI listener forwards on source IP info in it. */}}
        {{ if not (empty $server.SSLCertificate) }}
        {{ range $address := $all.Cfg.BindAddressIpv4 }}
        listen {{ $address }}:{{ if $all.IsSSLPassthroughEnabled }}{{ $all.ListenPorts.SSLProxy }} proxy_protocol {{ else }}{{ $all.ListenPorts.HTTPS }}{{ if $all.Cfg.UseProxyProtocol }} proxy_protocol{{ end }}{{ end }} {{ if eq $server.Hostname "_"}} default_server reuseport backlog={{ $all.BacklogSize }}{{end}} ssl {{ if $all.Cfg.UseHTTP2 }}http2{{ end }};
        {{ else }}
        listen {{ if $all.IsSSLPassthroughEnabled }}{{ $all.ListenPorts.SSLProxy }} proxy_protocol {{ else }}{{ $all.ListenPorts.HTTPS }}{{ if $all.Cfg.UseProxyProtocol }} proxy_protocol{{ end }}{{ end }} {{ if eq $server.Hostname "_"}} default_server reuseport backlog={{ $all.BacklogSize }}{{end}} ssl {{ if $all.Cfg.UseHTTP2 }}http2{{ end }};
        {{ end }}
        {{ if $all.IsIPV6Enabled }}
        {{ range $address := $all.Cfg.BindAddressIpv6 }}
        {{ if not (empty $server.SSLCertificate) }}listen {{ $address }}:{{ if $all.IsSSLPassthroughEnabled }}{{ $all.ListenPorts.SSLProxy }} proxy_protocol{{ else }}{{ $all.ListenPorts.HTTPS }}{{ if $all.Cfg.UseProxyProtocol }} proxy_protocol{{ end }}{{ end }}{{ end }} {{ if eq $server.Hostname "_"}} default_server reuseport backlog={{ $all.BacklogSize }}{{end}} ssl {{ if $all.Cfg.UseHTTP2 }}http2{{ end }};
        {{ else }}
        {{ if not (empty $server.SSLCertificate) }}listen [::]:{{ if $all.IsSSLPassthroughEnabled }}{{ $all.ListenPorts.SSLProxy }} proxy_protocol{{ else }}{{ $all.ListenPorts.HTTPS }}{{ if $all.Cfg.UseProxyProtocol }} proxy_protocol{{ end }}{{ end }}{{ end }} {{ if eq $server.Hostname "_"}} default_server reuseport backlog={{ $all.BacklogSize }}{{end}} ssl {{ if $all.Cfg.UseHTTP2 }}http2{{ end }};
        {{ end }}
        {{ end }}
        {{/* comment PEM sha is required to detect changes in the generated configuration and force a reload */}}
        # PEM sha: {{ $server.SSLPemChecksum }}
        ssl_certificate                         {{ $server.SSLCertificate }};
        ssl_certificate_key                     {{ $server.SSLCertificate }};
        {{ if not (empty $server.SSLFullChainCertificate)}}
        ssl_trusted_certificate                 {{ $server.SSLFullChainCertificate }};
        ssl_stapling                            on;
        ssl_stapling_verify                     on;
        {{ end }}
        {{ end }}

        {{ if (and (not (empty $server.SSLCertificate)) $all.Cfg.HSTS) }}
        more_set_headers                        "Strict-Transport-Security: max-age={{ $all.Cfg.HSTSMaxAge }}{{ if $all.Cfg.HSTSIncludeSubdomains }}; includeSubDomains{{ end }};{{ if $all.Cfg.HSTSPreload }} preload{{ end }}";
        {{ end }}


        {{ if not (empty $server.CertificateAuth.CAFileName) }}
        # PEM sha: {{ $server.CertificateAuth.PemSHA }}
        ssl_client_certificate                  {{ $server.CertificateAuth.CAFileName }};
        ssl_verify_client                       {{ $server.CertificateAuth.VerifyClient }};
        ssl_verify_depth                        {{ $server.CertificateAuth.ValidationDepth }};
        {{ if not (empty $server.CertificateAuth.ErrorPage)}}
        error_page 495 496 = {{ $server.CertificateAuth.ErrorPage }};
        {{ end }}
        {{ end }}

        {{ if not (empty $server.ServerSnippet) }}
        {{ $server.ServerSnippet }}
        {{ end }}

        {{ range $location := $server.Locations }}
        {{ $path := buildLocation $location }}
        {{ $authPath := buildAuthLocation $location }}

        {{ if not (empty $location.Rewrite.AppRoot)}}
        if ($uri = /) {
            return 302 {{ $location.Rewrite.AppRoot }};
        }
        {{ end }}

        {{ if not (empty $authPath) }}
        location = {{ $authPath }} {
            internal;
            set $proxy_upstream_name "external-authentication";

            proxy_pass_request_body     off;
            proxy_set_header            Content-Length "";

            {{ if not (empty $location.ExternalAuth.Method) }}
            proxy_method                {{ $location.ExternalAuth.Method }};
            proxy_set_header            X-Original-URI          $request_uri;
            proxy_set_header            X-Scheme                $pass_access_scheme;
            {{ end }}

            proxy_set_header            Host                    {{ $location.ExternalAuth.Host }};
            proxy_set_header            X-Original-URL          $scheme://$http_host$request_uri;
            proxy_set_header            X-Original-Method       $request_method;
            proxy_set_header            X-Auth-Request-Redirect $request_uri;
            proxy_set_header            X-Sent-From             "nginx-ingress-controller";

            proxy_http_version          1.1;
            proxy_ssl_server_name       on;
            proxy_pass_request_headers  on;
            client_max_body_size        "{{ $location.Proxy.BodySize }}";
            {{ if isValidClientBodyBufferSize $location.ClientBodyBufferSize }}
            client_body_buffer_size     {{ $location.ClientBodyBufferSize }};
            {{ end }}

            set $target {{ $location.ExternalAuth.URL }};
            proxy_pass $target;
        }
        {{ end }}

        location {{ $path }} {
            {{ if $all.Cfg.EnableVtsStatus }}{{ if $location.VtsFilterKey }} vhost_traffic_status_filter_by_set_key {{ $location.VtsFilterKey }};{{ end }}{{ end }}

            set $proxy_upstream_name "{{ buildUpstreamName $server.Hostname $all.Backends $location }}";

            {{ $ing := (getIngressInformation $location.Ingress $path) }}
            {{/* $ing.Metadata contains the Ingress metadata */}}
            set $namespace      "{{ $ing.Namespace }}";
            set $ingress_name   "{{ $ing.Rule }}";
            set $service_name   "{{ $ing.Service }}";

            {{ if (or $location.Rewrite.ForceSSLRedirect (and (not (empty $server.SSLCertificate)) $location.Rewrite.SSLRedirect)) }}
            # enforce ssl on server side
            if ($pass_access_scheme = http) {
                {{ if ne $all.ListenPorts.HTTPS 443 }}
                {{ $redirect_port := (printf ":%v" $all.ListenPorts.HTTPS) }}
                return {{ $all.Cfg.HTTPRedirectCode }} https://$best_http_host{{ $redirect_port }}$request_uri;
                {{ else }}
                return {{ $all.Cfg.HTTPRedirectCode }} https://$best_http_host$request_uri;
                {{ end }}
            }
            {{ end }}

            {{ if $all.Cfg.EnableModsecurity }}
            modsecurity on;

            modsecurity_rules_file /etc/nginx/modsecurity/modsecurity.conf;
            {{ if $all.Cfg.EnableOWASPCoreRules }}
            modsecurity_rules_file /etc/nginx/owasp-modsecurity-crs/nginx-modsecurity.conf;
            {{ end }}
            {{ end }}

            {{ if isLocationAllowed $location }}
            {{ if gt (len $location.Whitelist.CIDR) 0 }}
            if ({{ buildDenyVariable (print $server.Hostname "_"  $path) }}) {
                return 403;
            }
            {{ end }}

            port_in_redirect {{ if $location.UsePortInRedirects }}on{{ else }}off{{ end }};

            {{ if not (empty $authPath) }}
            # this location requires authentication
            auth_request        {{ $authPath }};
            auth_request_set    $auth_cookie $upstream_http_set_cookie;
            add_header          Set-Cookie $auth_cookie;
            {{- range $idx, $line := buildAuthResponseHeaders $location }}
            {{ $line }}
            {{- end }}
            {{ end }}

            {{ if not (empty $location.ExternalAuth.SigninURL) }}
            error_page 401 = {{ buildAuthSignURL $location.ExternalAuth.SigninURL }};
            {{ end }}

            {{/* if the location contains a rate limit annotation, create one */}}
            {{ $limits := buildRateLimit $location }}
            {{ range $limit := $limits }}
            {{ $limit }}{{ end }}

            {{ if $location.BasicDigestAuth.Secured }}
            {{ if eq $location.BasicDigestAuth.Type "basic" }}
            auth_basic "{{ $location.BasicDigestAuth.Realm }}";
            auth_basic_user_file {{ $location.BasicDigestAuth.File }};
            {{ else }}
            auth_digest "{{ $location.BasicDigestAuth.Realm }}";
            auth_digest_user_file {{ $location.BasicDigestAuth.File }};
            {{ end }}
            proxy_set_header Authorization "";
            {{ end }}

            {{ if $location.CorsConfig.CorsEnabled }}
            {{ template "CORS" $location }}
            {{ end }}

            {{ if not (empty $location.Redirect.URL) }}
            if ($uri ~* {{ $path }}) {
                return {{ $location.Redirect.Code }} {{ $location.Redirect.URL }};
            }
            {{ end }}

            client_max_body_size                    "{{ $location.Proxy.BodySize }}";
            {{ if isValidClientBodyBufferSize $location.ClientBodyBufferSize }}
            client_body_buffer_size                 {{ $location.ClientBodyBufferSize }};
            {{ end }}

            {{/* By default use vhost as Host to upstream, but allow overrides */}}
            {{ if not (empty $location.UpstreamVhost) }}
            proxy_set_header Host                   "{{ $location.UpstreamVhost }}";
            {{ else }}
            proxy_set_header Host                   $best_http_host;
            {{ end }}


            # Pass the extracted client certificate to the backend
            {{ if not (empty $server.CertificateAuth.CAFileName) }}
            {{ if $server.CertificateAuth.PassCertToUpstream }}
            proxy_set_header ssl-client-cert        $ssl_client_escaped_cert;
            {{ else }}
            proxy_set_header ssl-client-cert        "";
            {{ end }}
            proxy_set_header ssl-client-verify      $ssl_client_verify;
            proxy_set_header ssl-client-dn          $ssl_client_s_dn;
            {{ else }}
            proxy_set_header ssl-client-cert        "";
            proxy_set_header ssl-client-verify      "";
            proxy_set_header ssl-client-dn          "";
            {{ end }}

            # Allow websocket connections
            proxy_set_header                        Upgrade           $http_upgrade;
            proxy_set_header                        Connection        $connection_upgrade;

            proxy_set_header X-Real-IP              $the_real_ip;
            {{ if $all.Cfg.ComputeFullForwardedFor }}
            proxy_set_header X-Forwarded-For        $full_x_forwarded_for;
            {{ else }}
            proxy_set_header X-Forwarded-For        $the_real_ip;
            {{ end }}
            proxy_set_header X-Forwarded-Host       $best_http_host;
            proxy_set_header X-Forwarded-Port       $pass_port;
            proxy_set_header X-Forwarded-Proto      $pass_access_scheme;
            proxy_set_header X-Original-URI         $request_uri;
            proxy_set_header X-Scheme               $pass_access_scheme;

            # Pass the original X-Forwarded-For
            proxy_set_header X-Original-Forwarded-For {{ buildForwardedFor $all.Cfg.ForwardedForHeader }};

            # mitigate HTTPoxy Vulnerability
            # https://www.nginx.com/blog/mitigating-the-httpoxy-vulnerability-with-nginx/
            proxy_set_header Proxy                  "";

            # Custom headers to proxied server
            {{ range $k, $v := $all.ProxySetHeaders }}
            proxy_set_header {{ $k }}                    "{{ $v }}";
            {{ end }}

            proxy_connect_timeout                   {{ $location.Proxy.ConnectTimeout }}s;
            proxy_send_timeout                      {{ $location.Proxy.SendTimeout }}s;
            proxy_read_timeout                      {{ $location.Proxy.ReadTimeout }}s;

            {{ if (or (eq $location.Proxy.ProxyRedirectFrom "default") (eq $location.Proxy.ProxyRedirectFrom "off")) }}
            proxy_redirect                          {{ $location.Proxy.ProxyRedirectFrom }};
            {{ else }}
            proxy_redirect                          {{ $location.Proxy.ProxyRedirectFrom }} {{ $location.Proxy.ProxyRedirectTo }};
            {{ end }}
            proxy_buffering                         off;
            proxy_buffer_size                       "{{ $location.Proxy.BufferSize }}";
            proxy_buffers                           4 "{{ $location.Proxy.BufferSize }}";
            proxy_request_buffering                 "{{ $location.Proxy.RequestBuffering }}";

            proxy_http_version                      1.1;

            proxy_cookie_domain                     {{ $location.Proxy.CookieDomain }};
            proxy_cookie_path                       {{ $location.Proxy.CookiePath }};

            # In case of errors try the next upstream server before returning an error
            proxy_next_upstream                     {{ buildNextUpstream $location.Proxy.NextUpstream $all.Cfg.RetryNonIdempotent }};

            {{/* rewrite only works if the content is not compressed */}}
            {{ if $location.Rewrite.AddBaseURL }}
            proxy_set_header                        Accept-Encoding     "";
            {{ end }}

            {{/* Add any additional configuration defined */}}
            {{ $location.ConfigurationSnippet }}

            {{ if not (empty $all.Cfg.LocationSnippet) }}
            # Custom code snippet configured in the configuration configmap
            {{ $all.Cfg.LocationSnippet }}
            {{ end }}

            {{/* if we are sending the request to a custom default backend, we add the required headers */}}
            {{ if (hasPrefix $location.Backend "custom-default-backend-") }}
            proxy_set_header       X-Code             503;
            proxy_set_header       X-Format           $http_accept;
            proxy_set_header       X-Namespace        $namespace;
            proxy_set_header       X-Ingress-Name     $ingress_name;
            proxy_set_header       X-Service-Name     $service_name;
            {{ end }}


            {{ if not (empty $location.Backend) }}
            {{ buildProxyPass $server.Hostname $all.Backends $location }}
            {{ else }}
            # No endpoints available for the request
            return 503;
            {{ end }}
            {{ else }}
            # Location denied. Reason: {{ $location.Denied }}
            return 503;
            {{ end }}
        }

        {{ end }}

        {{ if eq $server.Hostname "_" }}
        # health checks in cloud providers require the use of port {{ $all.ListenPorts.HTTP }}
        location {{ $all.HealthzURI }} {
            access_log off;
            return 200;
        }

        # this is required to avoid error if nginx is being monitored
        # with an external software (like sysdig)
        location /nginx_status {
            allow 127.0.0.1;
            {{ if $all.IsIPV6Enabled }}allow ::1;{{ end }}
            deny all;

            access_log off;
            stub_status on;
        }

        {{ end }}

{{ end }}