Smartsocket is a zero dependency library for building websocket-based single page web applications, suitable for trading systems in the finance industry. It is based off the reconnecting-websocket library by Joe Walnes and the book Serverless Single Page Apps by Ben Rady.
A common technique in the finance industry is to record application state as a series of Add/Remove/Modify events. These events are used to create a Map that holds the state, matching keys (ex: an Order Id) to complex objects (ex: an Order message). This makes it easy to "snapshot" the application state by generating a sequence of synthetic add events, one for each entry in the Map. This technique has been successfully used in both trading systems and electronic exchanges. Smartsocket brings this technique to web applications, allowing for efficient incremental updates of data in real time.
Like many single page applications, Smartsocket keeps track of view state by changing the URL hash. This allows the application to switch from one "view" to another without reloading the page. This not only makes for a smoother user experience, but also makes it easy to persist and cache data between page transitions. Resources like sockets and timers are cleaned up automatically when the router changes to a new view.
Smartsocket uses the web standard template element for HTML templating, allowing you to build simple web applications without any external dependencies.
We believe that you should be able to create fast, informative, and reliable automated tests for every aspect of your web application. Smartsocket is designed with that goal in mind. It provides a fake window implementation that, while not a comprehensive impelemention of the web standard, is sufficient to control every aspect of browser behavior that you need to test an application built with Smartsocket.
Here are some things you you might expect to have in a "web framework". Smartsocket doesn't have these.
- Data binding
- A virtual DOM
- A server (aside from the example server)
For a demo, clone the repository and run make example. Each view in this application demonstrates a different part of Smartsocket's functionality.
Do you have to use all of this at once?
No! You can use the WebSocket without using the router. You can use the router without using the templates. You can use the templates without using the WebSocket. If you DO use all these things together, you get some nice guarantees about how they work together, but you can use them all seperately.
How do I install it?
Download a version and add smartsocket.js to your application. If you want to write tests, you'll probably want to add support.js as well.
Is there an NPM installation?
Not yet
Is it available in a CDN?
Not yet