go-testwire

An easy-to-use API to add test automation probes.

Introduction

This library provides an easy-to-use API to add test probes to your code. These probes can be used to retrieve information of your application that is normally not exposed.

This can be used to assert certain conditions in your applications that would otherwise be hard to assert while performing automated tests (black-box tests).

When testing an API, you can perform a request, and maybe another one to assert a condition. But if you are working with hardware, it might be valueable to assert that an API request perfoms a certain hardware action on the lower level.

A test scenario could look like this:

Given a running system
When I start the motor via the API
Then the response is successful
And the hardware turns on the power of the motor

This library may be useful to provide an implementation of the last step: it is information that is typically not exposed via an API. By probing into the communication layer with the hardware, we can now use this library to observe the 'internals'.

Usage

You need to explicitly enable TestWire support by compiling your application with the testwire tag set, e.g. go build -tags testwire main.go.

Without this tag, a 'disabled' version of testwire is compiled that provides stubs.

Adding probes and signals

Probes retrieve information, signals perform actions. They both assume that data can be returned as a string.

To add a probe, add the following:

testwire.AddProbe("probe.name", func() string {
    return "Foo"
})

To add a signal, add the following:

testwire.AddSignal("signal.name", func(s string) {
    log.Printf("Signal data: %s", s)
})

Serving

To start serving, simply add:

go testwire.Serve(port number)

API

Probes are exposed on http://localhost:9000/probes/probe.name. A GET request returns the probe value. Signals can be invoked by performing a POST request to http://localhost:9000/signals/signal.name.

License

See the LICENSE.md file (MIT license).

basilfx/go-testwire