topdog

topdog is a simple Go application that is used to demonstrate some [Istio] features. See the full example at https://github.com/ancientlore/istio-talk.

topdog is designed to be run with three tiers. To build it locally:

$ got get github.com/ancientlore/topdog

Run the application from the topdog folder where you built it. To start the backend tier:

$ ./topdog -service_port 5002

To start the middle tier:

$ ./topdog -service_port 5001 -backend http://localhost:5002

To start the UI:

$ ./topdog -service_port 5000 -midtier http://localhost:5001

Then nagivate to http://localhost:5000/ to see the user interface.

Alternately, you can run it all in one step using:

$ ./topdog -service_port 5000 -midtier http://localhost:5000 -backend http://localhost:5000

This is the same as just running topdog, since those values are the defaults.

In this case, it will use the same process for all three.

When running the backend, you can set the version command-line argument (or the VERSION environment variable) to values from 1 to 3. This makes the service weigh its results differently.