我可以在一条路由中多次使用npm request并将结果显示在同一页面上吗？

Question

Is there a way to use node module "request" multiple times in one route and have the results display on the same rendered ejs template page?

Goal: I want to display eBook information from the iTunes Store using their Search API. Right now I can get an ebook's price in one territory, but I would like to display prices for the same ebook in multiple countries. To get each different price, I need to use a different URL, either a default ending, "&country=gb", "&country=fr" etc. I can get prices for each of the 5 countries I am interested in, but I can't get them all on the same page. How can I construct my route and prepare my variables so that I can display information from all of these countries when I render one page?

I am using node, express and ejs, and I am making the http request using the "request" node module. Here are the basics of the form I'm using, where I enter the ISBN in the searchTerm field. (there's more, but it's bulky.)

<form action="/search">
  <select name="searchTerm">

Code that is working now for getting info on the book in one territory:

app.get('/search', function(req, res){
  var searchRequest = req.query.searchTerm;
  var searchURL = "http://itunes.apple.com/lookup?isbn=" + searchRequest;
  request(searchURL, function(error, response, body){
    if (!error && response.statusCode == 200) {
      var data = JSON.parse(body);
      console.log(data.results[0]);
      var iTunesResults = data.results[0];
      res.render("test", {
        iTunesResults: iTunesResults,
        searchRequest: searchRequest
      });
    }
  });
});

If I make a few changes in this code I can get information on the same ebook in a different country with just a few changes. Below is the code for great britain, and it works on its own, I just want to get results from both of these searches displaying at once, and I'm not sure where to begin.

app.get('/search', function(req, res){
  var searchRequest = req.query.searchTerm;
  var gbSearchURL = "http://itunes.apple.com/lookup?isbn=" + searchRequest + "&country=gb";
  request(gbSearchURL, function(error, response, body){
  if (!error && response.statusCode == 200) {
    var data = JSON.parse(body);
    console.log(data.results[0]);
    var iTunesResults = data.results[0];
    res.render("test", {
      iTunesResults: iTunesResults,
      searchRequest: searchRequest
    });
    }
  });
});

What I want to do is make an additional request to Apple, using the same search term here but adding a country identifier to the end of the searchURL I'm passing into request. However, if I try to call request again and pass all of the results variables into res.render at once, the result of the first request will not be available inside the second request.("ReferenceError: iTunesResults is not defined")

I'm guessing there is a way to have an array of searchURL's and an array of results (req.query.searchTerm), then I can pass the array or a more complicated object in when I render the test.ejs template. Am limited to one http request per app.get route? (Forgive me if that should be obvious, but I just want to grab this pricing information and display it next to each other. Also, I figured it would be better to be verbose in my question.)

Answer 1

Ok! I got it resolved using the "async" node library. http://www.github.com/caolan/async

With that I can call multiple functions in parallel, and when they're done I can just pass back the results to a template to render.

app.get('/search', function(req, res){
  async.parallel([
    function(done){
    var searchRequest = req.query.searchTerm;
    var gbSearchURL = "http://itunes.apple.com/lookup?isbn=" + searchRequest + "&country=us";
    request(gbSearchURL, function(error, response, body){
      if (!error && response.statusCode == 200) {
        // console.log(body) 
        var data = JSON.parse(body);
        // below shows whole object of result 0
        console.log(data.results[0]);
        done(null, data.results[0]);
      }
    });
  },
  // UK pricing
    function(done){
      var searchRequest = req.query.searchTerm;
      var gbSearchURL = "http://itunes.apple.com/lookup?isbn=" + searchRequest + "&country=gb";
      request(gbSearchURL, function(error, response, body){
        if (!error && response.statusCode == 200) {
          // console.log(body) 
          var data = JSON.parse(body);
          // below shows whole object of result 0
          console.log(data.results[0]);
          done(null, data.results[0]);
        }
      });
    },function(err, iTunesResults){
      res.render("test", {
        iTunesResults: iTunesResults,
        searchRequest: req.query.searchTerm
      });
  })
});