Okay, so today I’m gonna walk you through my little project: setting up some real basic Ruby (rb) streamers. Nothing fancy, just getting data from somewhere and spitting it out in a stream. Let’s dive right in.
First Things First: The Gem Setup
Alright, so the first thing I did was get the basic Ruby environment ready. I made sure I had Ruby installed, obviously. Then I started a new project folder and initialized a Gemfile. Inside the Gemfile, I needed a couple of gems. I used `sinatra` for the web server part because it’s lightweight and easy to use. I also snagged a gem to handle the data – for this example, let’s just pretend it’s a CSV file, so I used `csv`. So, I added these lines:
`gem ‘sinatra’`
`gem ‘csv’`
After that, I ran `bundle install` to get all the gems installed and ready to rock.
The Core: Streaming Action
Next up, I created my main Ruby file, let’s call it `*`. Here’s where the magic happens. I required the gems I installed earlier:
require 'sinatra'
require 'csv'
Now, the Sinatra part. I set up a basic route for the stream. The key here is setting the `Content-Type` to `text/event-stream`. This tells the browser that we’re sending a stream of data.
get '/stream' do
content_type 'text/event-stream'
stream do out
# Streaming logic goes here
end
end
Inside the `stream` block, that’s where I read the CSV file (or whatever data source you’re using) and push the data out. To keep it simple, I looped through the CSV rows and sent each row as a separate event. Remember to format it correctly for the event stream. Each event should have a `data:` line, followed by the actual data, and then a blank line to separate the events.
*("*", headers: true) do row
out << "data: #{*_json}nn"
sleep 1 # Added a small delay to make it easier to see
end
I added a `sleep 1` to slow things down, otherwise, it would just blast through the entire file in a second. You can adjust that delay as needed.
Frontend Magic: Catching the Stream
Now, to the frontend! I made a simple HTML file to catch the stream and display the data. I used JavaScript’s `EventSource` API, which is perfect for handling server-sent events.
<!DOCTYPE html>
<html>
<head>
<title>Ruby Streamer</title>
</head>
<body>
<div id="data-container"></div>
<script>
const eventSource = new EventSource('/stream');
* = function(event) {
const data = *(*);
const container = *('data-container');
* += '<p>' + *(data) + '</p>';
* = function(error) {
*("EventSource failed:", error);
</script>
</body>
</html>
This code creates an `EventSource` that connects to the `/stream` endpoint. Whenever a new event comes in, it parses the JSON data and adds it to a `div` on the page. The `onerror` part is important to handle disconnects or any other issues with the stream.
Running the Show
To run it, I just fired up the Ruby server with `ruby *`. Then, I opened the HTML file in my browser. And bam! The data started streaming into the page. It wasn’t pretty, but it worked!
Wrapping Up
That’s pretty much it. A super basic Ruby streamer. Of course, this is just scratching the surface. You could add error handling, more sophisticated data formatting, different data sources, and all sorts of other bells and whistles. But this gives you a solid starting point. Go forth and stream!