vcl 4.0;

backend default {
	.host			= "haproxy";
	.port			= "80";
	.max_connections	= 300;
	.first_byte_timeout	= 240s;
	.connect_timeout	= 10s;
	.between_bytes_timeout	= 2s;
	.proxy_header		= 2;
}
sub vcl_recv {
	if (	req.method != "GET" &&
		req.method != "HEAD" &&
		req.method != "PUT" &&
		req.method != "POST" &&
		req.method != "TRACE" &&
		req.method != "OPTIONS" &&
		req.method != "PATCH" &&
		req.method != "DELETE") {
			return (pipe);
	}
	if (req.http.Upgrade ~ "(?i)websocket") {
		return (pipe);
	}
	if (req.method == "GET" || req.method == "HEAD") {
		return (hash);
	}
	return (pass);
}
sub vcl_hash {
	hash_data(req.url);
	if (req.http.cookie) {
		hash_data(req.http.cookie);
	}
	return (lookup);
}
sub vcl_hit {
	if (obj.ttl + obj.grace > 0s) {
		return (deliver);
	}
	return (pass);
}
sub vcl_miss {
	return (fetch);
}
sub vcl_pipe {
	if (req.http.upgrade) {
		set bereq.http.upgrade = req.http.upgrade;
	}
	return (pipe);
}
sub vcl_backend_response {
	if (beresp.status == 500 || beresp.status == 502 || beresp.status == 503 || beresp.status == 504) {
		return (abandon);
	}
	if (beresp.http.Cache-Control ~ "public") {
		return (deliver);
	}
	return (pass);
}