Sample components of a gnericized version of edm00se/express-domino-nsf app on GitHub, for inclusion in my blog series (post 1/3). https://github.com/edm00se/express-domino-nsf

config_index.js

/*  file: /config/index.js */
var something = process.env.SOME_INFO || 'someVal'; // env var of SOME_INFO, defaulting to 'someVal'

module.exports = {
	someInfo: somthing
};

d-config_db.js

var srvNm = process.env.DOM_SRV || '';
var dbNm = process.env.DOM_DB || 'SomeApp.nsf';

module.exports = {
	db: {server:srvNm,database:dbNm}
};

d-routes_beers.js

var util = require('../util');

module.exports = function (app) {

    app.get("/beers", function(req, res, next){
    	var resp = {};
    	util.getView('beers',function(err,data){
            if(err){
                resp = {
                    "error": true,
                    "message": err
                };
            } else {
                resp = {
                    "error": false,
                    "data": data
                };
            }
            res.jsonp(resp);
        });
    });
    
};

d-util_index.js

var domino = require('domino-nsf'),
  config = require('../config/db.js'),
  db = config.db;

// initialize Session
function initSession(cb){
  domino.initSession();
  cb();
};

// terminate Session
function closeSession(){
  domino.termSession();
};

// get Document contents by UNID
function getDocumentByUnid(un,cb){
  initSession(function(){
    domino.getDocumentAsync(db,un,function(err,doc){
      if(!err){
        cb(null,doc);
      }else{
        cb(err);
        console.log('Error: '+err);
      }
      closeSession();
    });
  });
};

// get View contents by View name
function getViewContents(vw,cb){
  var vwOb = {view:vw,category:""};
  initSession(function(){
    domino.getViewAsync(db,vwOb,function(err,view) {
      if(!err){
        cb(null,view);
      }else{
        cb(err);
        console.log('Error: '+err);
      }
      closeSession();
    });
  });
};

// exporting what we care about in a structured format
module.exports = {
  getView: getViewContents,
  getDoc: getDocumentByUnid
};

i-config_db.js

var path = require('path');

var jarFilePath = path.join(__dirname, '../lib', 'jt400.jar');
var driverNm = 'com.ibm.as400.access.AS400JDBCDriver';
var addr = process.env.URL || 'as400://ibmi.fullyqualifiedname.com';
var uName = process.env.ISERIES_USER_NAME || 'user';
var pWord = process.env.ISERIES_PASSWORD || 'secret';

// a config object w/ specifics for the connection
module.exports = {
	libpath: jarFilePath,
	drivername: driverNm,
	url: addr,
	user: uName,
	password: pWord,
};

i-routes_beers.js

var util = require('../util');

module.exports = function (app) {

    app.get("/beers", function(req, res, next){
    	var resp = {};
    	util.query("SELECT * FROM beers", function(err, data){
    		if(err){
    			resp = {
    				"error": true,
    				"message": err
    			};
    		} else {
    			resp = {
    				"error": false,
    				"data": data
    			};
    		}
    	});
        res.jsonp(resp);
    });
    
};

i-util_index.js

var jdbc = new ( require('jdbc-pro') );
var dbConf = require('../config/db.js');

// handler to initialize the connection
function initCon(cb){
  jdbc.initialize(dbConf, function(err, res) {
    if (err) {
      console.log(err);
    } else {
      console.log("Connection initialized successfully!");
      cb(null);
    }
  });
};

// handler to close the connection
function closeCon(err) {
  if(err) {
    console.log(err);
  } else {
    console.log("Connection closed successfully!");
  }
};

// wrapping the func, passing results or error via callback
function getQueryResults(sql,cb){
  initCon(function(err){
    if(err){
      console.log(err);
    } else {
      jdbc.open(function(err, conn) {
        if (conn) {
          // perform passed SQL statement, SELECT statement
          jdbc.executeQuery(sql, function(err, results) {
            if(err){
              console.log(err);
              cb(err,null);
            } else {
              cb(null,results);
            }
            closeCon(); // lastly, close the connection
          });
        }
      });
    }
  });
};

// separately wrapped func for UPDATE or INSERT
function getUpdateResults(sql,cb){
  initCon(function(err){
    jdbc.open(function(err, conn) {
      if (conn) {
        // perform passed SQL statement, INSERT or UPDATE
        jdbc.executeUpdate(sql, function(err, results) {
          if(err){
            console.log(err);
            cb(err,null);
          } else {
            cb(null,results);
          }
          closeCon();
        });
      }
    });
  });
};

// exporting what we care about in a structured format
module.exports = {
  query: getQueryResults,
  update: getUpdateResults
};

public_readme.html

<!-- file: /public/readme.html -->
<!doctype html>
<html>
  <head>
    <title>Instructions</title>
  </head>
  <body>
    <h3>Instructions for Use</h3>
    <p>TODO: Describe your API endpoint's behavior and how to interact with it.</p>
  </body>
</html>

routes_index.js

/*  file: /routes/index.js */
var path = require('path')

// export a function that accepts `app` as a param
module.exports = function (app) {
    app.get('/', function (req, res, next) {
        res.sendFile(path.join(__dirname, '../public', 'readme.html'));
    });
    
    // this should be in a `beers.js` file, pulled in by require('./beers')
    app.get('/beers', function(req, res, next){
        res.send('beers!');
    });
    
    // require('./breweries')(app);
    // require('./vineyards')(app);
    // add new lines for each other endpoint defined in its own file for simplicity
};

server.js

/*  file: /server.js */
var express = require('express'),
  app = express(),
  os = require('os');

//enables and instantiates express-toobusy, which keeps it from melting under HIGH pressure
app.use(require('express-toobusy')());

require("./routes")(app);

//establish simple text catch for Error 500
app.use(function(err, req, res, next){
  console.error(err.stack);
  res.status(500).send("<h1>Error 500</h1>\nSomething broke! The error has been logged to the server console.");
});

//set to listen on environment port or port 3333, if no detected env var port
var portToListenOn = process.env.PORT || 3333;
app.listen(portToListenOn, function(){
  console.log("NodeJS serving content from "+__dirname+" on "+os.hostname()+":"+portToListenOn);
});