Limit payload size using a reverse-proxy or a middleware

http {
    # Limit the body size for ALL incoming requests to 1 MB
}
server {
    ...
    # Limit the body size for incoming requests to this specific server block to 1 MB
location /upload {
    ...
    # Limit the body size for incoming requests to this route to 1 MB
    client_max_body_size 1m;
}