enginyoyen

server {
        set $response_body '';  #we must declare variables first, we cannot create vars in lua
        set $error_request_body '';
        set $error_response_body '';
        body_filter_by_lua '
            local resp_body = string.sub(ngx.arg[1], 1, 1000)  -- arg[1] contains a chunk of response content
            ngx.ctx.buffered = string.sub((ngx.ctx.buffered or "") .. resp_body, 1, 1000)
            if ngx.arg[2] then  -- arg[2] is true if this is the last chunk
              ngx.var.response_body = ngx.ctx.buffered
            end