Logging http request without authorization/token header express-winston on openapi-generator-cli server stub

I am trying to use express-winston to log on my nodejs-express-server app. This app is an openapi API server stub created from openapi-generator-cli.
Was referring to this post about excluding params while logging the request. My intention here is to detect authorization header ("api_token") in the request and mask its value. When I log request as is, without any filtering I see a massive log entry of about 1000+ lines after I JSON format it. I could use some pointers on

1. Masking selected headers (Using express-winston or any other library)
2. Reducing the request size on the log

Here's a filter I am trying out. Code follows.

    function maskTokenFilter(req, propName) {
      if(propName !== "headers" || propName !== "rawHeaders") {
        return req[propName];
      } 
      if(propName == "headers" ){
        const { api_token, ...rest } = req.headers;
        if(api_token) {
          return Object.assign({api_token: '*** masked ***'},rest);
        }   
      }
      if(propName == "rawHeaders" ){
        const { api_token, ...rest } = req.rawHeaders;
        if(api_token) {
          return Object.assign({api_token: '*** masked ***'},rest);
        }   
      }     
    }

The complete request entry on express-winston log is shared here. (Note: I JSON formatted it for readability)

from Logging http request without authorization/token header express-winston on openapi-generator-cli server stub