- Streaming APIs
- Signing Up for Twitter
- Using Twitter's API with Node.js
- Extracting Meaning from the Data
- Pushing Data to the Browser
- Creating a Real-Time Lovehateometer
- Summary
- Q&A
- Workshop
- Exercises
This chapter is from the book
This chapter is from the book
This chapter is from the book
Using Twitter’s API with Node.js
Once you create your application within the Twitter Developers website and request an OAuth access token, you are ready to start using the Twitter API. An excellent Node.js module is available for interacting with the Twitter API called ntwitter. This module was initially developed by technoweenie (Rick Olson), then jdub (Jeff Waugh), and is now maintained AvianFlu (Charlie McConnell). All the authors have done an amazing job of abstracting the complexity of interacting with Twitter’s API to make it trivial to get data and do things with it. You continue to use Express in this hour, so the package.json file for the application will include the Express and ntwitter modules.
{
"name":"socket.io-twitter-example",
"version":"0.0.1",
"private":true,
"dependencies":{
"express":"2.5.4",
"ntwitter":"0.2.10"
}
}
The ntwitter module uses OAuth to authenticate you, so you must provide four pieces of information:
- Consumer key
- Consumer secret
- Access token key
- Access token secret
If you requested these when you were setting up the application in the Twitter Developers website, these will be available on the Details page for your application. If you did not request them when you set up the application, you need to do so now under the Details tab. Once you have the keys and secrets, you can create a small Express server to connect to Twitter’s streaming API:
var app = require('express').createServer(),
twitter = require('ntwitter');
app.listen(3000);
var twit = new twitter({
consumer_key: 'YOUR_CONSUMER_KEY',
consumer_secret: 'YOUR_CONSUMER_SECRET',
access_token_key: 'YOUR_ACCESS_TOKEN_KEY',
access_token_secret: 'YOUR_ACCESS_TOKEN_KEY'
});
Of course, you need to remember to replace the values in the example with your actual values. This is all you need to start interacting with Twitter’s API! In this example, you answer the question, “Is there more love or hate in the world?” by using real-time data from Twitter. You request tweets from Twitter’s streaming API that mention the words “love” or “hate” and perform a small amount of analysis on the data to answer the question. The ntwitter module makes it easy to request this data:
twit.stream('statuses/filter', { track: ['love', 'hate'] }, function(stream) {
stream.on('data', function (data) {
console.log(data);
});
});
This requests data from the 'statuses/filter' endpoint that allows developers to track tweets by keyword, location, or specific users. In this case, we are interested in the keywords 'love' and 'hate'. The Express server opens a connection to the API server and listens for new data being received. Whenever a new data item is received, it writes the data to the console. In other words, you can see the stream live for the keywords “love” and “hate” in the terminal.
Try It Yourself
If you have downloaded the code examples for this book, this code is hour14/example01.
To stream data from Twitter, follow these steps:
- Create a new folder called express_twitter.
Within the express_twitter folder, create a new file called package.json and add the following content to declare ntwitter and Express as dependencies:
{ "name":"socket.io-twitter-example", "version":"0.0.1", "private":true, "dependencies":{ "express":"2.5.4", "ntwitter":"0.2.10" } }Within the express_twitter folder, create a new file called app.js with the following content. Remember to replace the keys and secrets with your own:
var app = require('express').createServer(), twitter = require('ntwitter'); app.listen(3000); var twit = new twitter({ consumer_key: 'YOUR_CONSUMER_KEY', consumer_secret: 'YOUR_CONSUMER_SECRET', access_token_key: 'YOUR_ACCESS_TOKEN_KEY', access_token_secret: 'YOUR_ACCESS_TOKEN_KEY' }); twit.stream('statuses/filter', { track: ['love', 'hate'] }, function(stream) { stream.on('data', function (data) { console.log(data); }); });Install the dependencies by running the following from a terminal:
npm install
Start the server by running the following from a terminal:
node app.js
Watch the terminal; you should see data being received from Twitter’s streaming API (see Figure 14.4). There is a lot of data, so expect it to move fast
Figure 14.4. Streaming data to the terminal
- Kill the server pressing Ctrl+C in the terminal.
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