app.js

var express = require('express');
var google = require('google');

var app = express();

function googleSearch(opts, callback) {
	var search = config(opts);
	var results = [], pages = 0;

	search(opts.query, function (err, next, links) {
		if (err) {
			return callback(err);
		}

		links = links.map(function (link) {
			return {title: link.title, link: link.link, description: link.description};
		});

		results = results.concat(links);

		if (pages < opts.nextPages) {
			pages =+ 1;
			next();
		} else {
			callback(null, {query: opts.query, results: results});
		}
	});

	function config(opts) {
		google.resultsPerPage = opts.resultsPerPage || 25;
		google.tld = opts.tld;
		google.lang = opts.lang;

		return google;
	}
}

app.get('/search', function (req, res, next) {
	var query = req.query.query;
	var lang = req.query.lang || 'en';
	var tld = req.query.tld || 'de';

	if (!query) {
		return res.status(400).json({message: 'query is missing'});
	}

	var opts = {
		query: query,
		lang: lang,
		tld: tld,
		resultsPerPage: 25,
		nextPages: 1
	};

	googleSearch(opts, function (err, results) {
		if (err) {
			return next(err);
		}

		res.json(results);
	});
});

app.listen(3322, function () {
	console.log('search service started on 3322');
});

package.json

{
  "name": "yes",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    "express": "^4.12.3",
    "google": "^0.6.0"
  }
}

Error object is not a function raised on line 23 next();
Any idea?

Alex, one more thing please.

I'm trying to format the response with not just the results but also query params. Problem is I'm having trouble pushing to the array.

Here is the expected results.
As you can see, I'd like to push search params to results and move search results under results

{
    "search": {
      "query" :  "my-keywords",
      "lang" : "en",
      "ltd" : "de"
    },
    "results" : [
         { "title" : "abc",
          "link" : "//",
          "description" : "blabla"
        },
        { "title" : "abc",
          "link" : "//",
          "description" : "blabla"
        }
    ]
}

This is what I tried:

results = results.search.push({
      "query" : opts.query
});
results = results.concat(links);

Error raised: Cannot call method 'push' of undefined

I've modified https://gist.github.com/alexbeletsky/a3ce02a05790e24a3176#file-app-js-L25 for that.

Thanks a lot. All good now.