TypeError: handler is not a constructor

[engin]

Hello, i'm getting an error just like the same as in the #36
But the weird thing is, the exception only happening on CI/CD which i tried to use both latest alpine and stretch images.
Here is the packages in use:

npm-check-updates
[INFO]: You can also use ncu as an alias
Checking /Users/engin/ips/kapca/package.json
[====================] 27/27 100%

 convict                     ^5.1.0  →   ^5.2.0
 core-js                    ^2.6.10  →   ^3.3.3
 debug                       ~2.6.9  →   ~4.1.1
 express                    ~4.16.1  →  ~4.17.1
 eslint                     ^4.19.1  →   ^6.5.1
 eslint-config-airbnb-base  ^12.1.0  →  ^14.0.0
 eslint-plugin-import       ^2.11.0  →  ^2.18.2
 husky                      ^0.14.3  →   ^3.0.9
 jest                       ^24.8.0  →  ^24.9.0
 nodemon                    ^1.17.3  →  ^1.19.4
 shx                         ^0.2.2  →   ^0.3.2
 supertest                   ^3.0.0  →   ^4.0.2

and here is the stack trace from the jest output

    TypeError: handler is not a constructor

      18 | // const mappedRoutes = mapRoutes(routes, 'api/controllers/');
      19 | // eslint-disable-next-line new-cap
    > 20 | const mappedRoutes = new mapRoutes(routes, 'api/controllers/');
         |                      ^
      21 | app.use('/', mappedRoutes);
      22 |
      23 |

      at node_modules/express-routes-mapper/lib/index.js:108:15
          at Array.forEach (<anonymous>)
      at new mapRoutes (node_modules/express-routes-mapper/lib/index.js:56:13)
      at Object.<anonymous> (config/routes.js:20:22)
      at require (test/_setup.js:18:3)
      at Object.beforeAction (test/controllers/CaptchaController.test.js:15:15)

[aichbauer]

Hey,

what version of node, and express routes mapper do you use?

do you use a lock file? do you have a different version of node, express routes mapper locally and on the ci/cd server?

[engin]

Hello @aichbauer ,

Sorry for the missing description. I don't use lock file; package-lock=false set in the .npmrc

Project dependencies

"dependencies": {
    "convict": "^5.2.0",
    "core-js": "^2.6.10",
    "express": "~4.17.1",
    "express-prettify": "^0.1.1",
    "express-prom-bundle": "^5.1.5",
    "express-routes-mapper": "^1.1.0",
    "express-validator": "^6.2.0",
    "got": "^9.6.0",
    "morgan": "~1.9.1",
    "prom-client": "^11.5.3",
    "redis": "^2.8.0",
    "svg-captcha": "^1.4.0",
    "uuid": "^3.3.3"
  },
  "devDependencies": {
    "eslint": "^6.5.1",
    "eslint-config-airbnb-base": "^14.0.0",
    "eslint-plugin-import": "^2.18.2",
    "husky": "^3.0.9",
    "jest": "^24.9.0",
    "nodemon": "^1.19.4",
    "redis-mock": "^0.46.0",
    "shx": "^0.3.2",
    "supertest": "^4.0.2"
  }

Local node version

➜  kapca (master) ✗ node --version
v12.10.0

Dockerfile

FROM node:12-alpine

WORKDIR /usr/src/app

COPY package*.json ./
RUN npm install

COPY . .

CMD ["npm", "run", "start"]

[aichbauer]

Can you test:

what happens if you add npm install core-js@2 -S and then run the job again?

what happens if you locally delete the node_modules folder and run npm i again?

what happens if you remove the npm uninstall core-js@2 -S dependency again and change the version of express-routes-mapper from ^ 1.1.0 to be explicitly 1.1.0?

[jglodek]

I got the exact message when I composed controller construction function return statement with too many endpoints. So linter should see that stuff was undefined.

[pdias94]

Got the same message, but the my controller was wrong. I did not export corectly, so the router did not find it.

[gulatichayan]

I have raised a pull request to resolve this issue.
#70