A simple 3-Tier application: keeping track of a visits on a website¶

TODO: Diagram

Introduction¶

Before we move to how to create such a system, it's important to focus on one aspect of codefly: the Developer Experience.

At codefly.ai, we believe that the time to onboard and time to setup should be ZERO.

With codefly and Docker installed, you should just pull a Git repository, and type codefly run service on the part of the system you want to run and it will.

Running things¶

Get the code¶

First, pull the repository with the backend that you want to use

• python

  https://github.com/codefly-dev/example-python-visitor.git
  

• go Coming soon

• Node Coming soon

Running everything¶

To run any service with codefly, you would use codefly run service in the service folder you want to run:

cd applications/web/services/frontend
codefly run service

Or you could run

codefly run service frontend

In case you have several services in the project with the same name (service name uniqueness is only required at the application level), you can specify the application as well: codefly run service web/frontend or run it anywhere inside the web application folder.

You should see some amount of logs and let's look at a few lines:

Running <frontend> with these dependent services: backend/store, backend/cache, backend/server

codefly recognizes that the frontend needs the backend to run which in turn requires the store and the cache.

So codefly will run these services for you, in the right order and waiting when it needs to.

So your database is ready when your service needs it.

backend/server >> will run on http://localhost:XXXX

This will be the local address for your backend server. Ports are automatically generated by codefly and are deterministic, based on project, application, service and API. We try to avoid port collision as best as we can: in other words, you can share configuration for your debug tools, swagger, kreya, DB client configurations, etc... Everyone gets the same setup!

Your frontend logs that also

web/frontend   >> will run on http://localhost:XXXX

Click on the url and you get

The website has a nice little nugget: by default, the Next.js agent creates a page that show you how in code you access your APIs:

For example, to fetch the data for the statistics, you would use codefly JavaScript SDK:

const { routing } = useCodeflyContext();
const url = routing(
    "GET",
    { application: "backend", service: "server" },
    "/visit/statistics"
)

CLI frontend companion¶

The CLI output is nice but it will quickly get quite busy. So codefly comes with its own frontend to help you developing.

Just add the --server flag will run a gRPC/http server with the CLI.

You can see in a glance the structure of your project. For example, clicking on one application will show you the services running and their dependencies

The companion also provides a convenient way to test your REST endpoints: