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Services

A service is one or more processes handling a common task. These processes operate as a tightly-coupled whole.

All processes in a service will generally:

• Share the same API class definitions
• Moreover, they will normally share the same codebase
• Create a single instance of the bus client in bus.py using bus = lightbus.create().

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For example, your company may have the following:

• An online store
• A price monitoring script
• An image resizing resizing process

Each of these would be a service.

The store service would have a web process and a Lightbus process. The image resizing service & and price monitoring services would each likely have a Lightbus process only.

A simple lightbus deployment could therefore look something like this:

In this example the following actions would take place:

• Django reads from the web service database in order to serve web content
• The online shop's Lightbus process receives pricing events from the price monitoring service. It updates products in the database using this new pricing data.
• When the Django app receives an image upload, it performs a RPC to the image resizing service to resize the image¹.

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1. Making the Django process wait for an RPC to respond is probably a bad idea in this case, but it illustrates how it could be done. Using an event (which is fire-and-forget) could be more suitable in reality. ↩