tests/

README

Layer0 Tests

This package contains all non-unit tests for Layer0, including system, smoke, and stress tests. The following instructions pertain to system and stress tests.

Test Architecture

Each test case contains two components: a subdirectory under cases/, and a <case name>_test.go file. The test case directory contains terraform files that outline the resources needed for the test. The resources for the test can be created with terraform apply before executing the test, and deleted with terraform destroy once the test has completed.

Note that the cases/modules directory is not a test case directory. It holds our terraform modules to reduce duplicate code in our terraform files.

If your test case was named my_simple_example, you should create the following files and directories:

layer0/tests/system
|-- mySimpleExample_test.go
|-- cases
|   |-- my_simple_example
|   |    |-- main.tf

Writing a Test

Writing a test is relatively straightforward. Following the example above, the contents of mySimpleExample_test.go should look like:

package system

import (
        "testing"
)

// Test Resources:
// This test creates an environment named 'mse' that has a
// SystemTestService named 'sts'
func TestMySimpleExample(t *testing.T) {
    t.Parallel()

    s := NewSystemTest(t, "cases/my_simple_example", nil)
    s.Terraform.Apply()
    defer s.Terraform.Destroy()
 
    // the rest of your test
}

Each test case should have its own file with a matching name. The test function has some comments about what resources are created by terraform (note: environment names are typically acronyms of the test case, e.g. "my_simple_example" = "mse").

The SystemTestService

Many system tests use the System Test Service, or STS. This is a simple web service whose behavior can be changed through an API.

Checkout the TestDeadServiceRecreated test to see how to use the STS client in a test.

Test Flags

In addition to the standard go test flags, the following have been implemented for system tests:

-debug - Test verbosity can be increased using the builtin -v flag, but this only shows output once the test has completed. If you need real time output, use the -debug flag and print statements with logrus.Debugf().

-dry - Using the -dry flag will swap terraform apply and destroy commands with plan. When developing a system test, waiting for terraform to setup/destroy the test resources can very time consuming. Using this method, you can run your test multiple times without terraform destroying and rebuilding the resources.

Some useful builtin flags:

• -run nameOfTest - Executes tests that match the specified name (can be used to run a single test case).
• -parallel n - Specifies the number of tests to run in parallel at once.
• -short - Execute the tests in short mode. Long running tests will be skipped.
• -timeout t - Specifies the timeout for the tests. The default is 10m, which typically isn't long enough to complete all of the system tests.