swagger with express nodejs APIs giving 404 error

I have configured swagger for my existing application which is implemented using express nodeJS.

server.js placed in the root folder and API's(*.js files) inside some other directories like

modules/data/first.js
modules/second.js
modules/config/getConfig.js

In the server.js file I declared apis as below

apis: ["./modules/data/first.js", "./modules/second.js", "./modules/config/getConfig.js"]

I added @swagger in all .js files and given

/first for the first.js file
/second for the second.js file
/third for the third.js file

When I open swagger-UI page, it is showing 3 APIs but when I click on anyone API then it is giving 404 response

Solution

Fixed the issue, problem is due to misconfiguration of app.use.

Initially there is no JWT token verification, so it worked but later JWT verification was introduced, then I faced 401 error ({"msg": "unauthorized"}) for swagger-UI page itself, I made some changes in the swagger options. Then UI page got opened with all endpoints, but when I click on any endpoints they started giving 404 error.

When I changed app.use to swagger first and then for my application endpoints it started working.