$remote_addr        The remote host
$remote_user        The authenticated user (if any)
$time_local         The time of the access
$request            The first line of the request
$status             The status of the request
$body_bytes_sent    The size of the server's response, in bytes
$http_referer       The referrer URL, taken from the request's headers
$http_user_agent    The user agent, taken from the request's headers

$request_body   请求体（含POST数据）
$http_XXX       指定某个请求头（XXX为字段名，全小写）
$cookie_XXX     指定某个cookie值（XXX为字段名，全小写）

log_format  big_api  '$remote_addr - $remote_user [$time_local] "$request" '
    '$status $body_bytes_sent "$request_body" "$http_referer" '
    '"$http_user_agent" $http_x_forwarded_for "appid=$http_appid,appver=$http_appver,vuser=$http_vuser" '
    '"phpsessid=$cookie_phpsessid,vuser_cookie=$cookie___vuser" ';

access_log  /home/wwwlogs/hicrew.log big_api;