How to specify rotated file location by using rotating-file-stream - node.js

Question

I have writtten code like below to log express logs.
const rfs = require("rotating-file-stream");
function formatDate() {
var d = new Date(),
month = '' + (d.getMonth() + 1),
day = '' + d.getDate(),
year = d.getFullYear();
hour = d.getHours();
if (month.length < 2)
month = '0' + month;
if (day.length < 2)
day = '0' + day;
if (hour.length < 2)
hour = '0' + hour
return [year, month, day, hour].join('-');
}
let log_directory = '/../logs/';
let log_date = formatDate()
let log_file_name = path.normalize(__dirname + log_directory + log_date, 'access.log');
let accessLogStream = rfs.createStream(log_file_name, {
size: "300M",
interval: "1d",
})
app.use(morgan(':date[iso] :method :url :body :headers :remote-addr :req[content-length] - :status :response-time ms - :res[content-length] ', { stream: accessLogStream }));
logs are getting stored out side of the project as expected.
But after rotation, the logs are storing inside the project with the below folder names
20200507-0943-01-
20200508-0943-01-
20200509-0943-01-
20200510-0943-01-
20200511-0943-01-
20200512-0943-01-
20200513-0944-01-
package.json
package-lock.json
public
routes
scripts
services
app.js
I don't want these folders created inside the project. Is there any way to handle this?

Answer 1

First of all you are using a static file name as filename parameter of createStream function and you are doing some computation on date to have your resulting file name.
Please note that the computation on date happens only once, before calling the createStream function. In order to do computation on date happening at each rotation you should use a filename generator function. Details can be found in readme.
More than this it seems there is a bug in this line: path.normalize accepts only one parameter.
let log_file_name = path.normalize(__dirname + log_directory + log_date, 'access.log');
Last, to specify a directory for logging, path option should be enough.
If I argued correctly your intentions, following code should solve all the problems
const rfs = require("rotating-file-stream");
function formatDate(d) {
var month = '' + (d.getMonth() + 1),
day = '' + d.getDate(),
year = d.getFullYear(),
hour = d.getHours();
if (month.length < 2)
month = '0' + month;
if (day.length < 2)
day = '0' + day;
if (hour.length < 2)
hour = '0' + hour;
return [year, month, day, hour].join('-');
}
function log_file_name(time, index) {
if (!time) return 'access.log';
return [formatDate(time), index, 'access.log'].join('-');
}
let accessLogStream = rfs.createStream(log_file_name, {
size: "300M",
interval: "1d",
path: '/../logs/'
});