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Developer Guide for the Integration and E2E Testing Framework

The agent testing framework allows running integration and end-to-end tests against real agents installed on remotely provisioned virtual machines. The current set of integration tests can be found in https://github.com/elastic/elastic-agent/tree/main/testing/integration. Each test must start with a define.Require declaration describing how the test can be run. The diagram below provides a high level overview of the testing framework.

Elastic Agent Testing Framework

Prerequisites

Dependencies

Go version should be at least the same than the one in .go-version file at the root of this repository

GCloud CLI

Configuration

ESS (staging) API Key to create on https://staging.found.no/account/keys

Warning: if you never created a deployment on it, you won't have permission to get this key, so you will need to create one first.

Running tests

Some integration and E2E tests are safe to run locally. These tests set Local: true in their test functions' define.Require directive. Tests that don't set Local: true or explicitly set Local: false are not considered safe to run locally and will be executed on remote VMs instead.

The framework will look for the agent version defined by the AGENT_VERSION environment variable, even for local tests, regardless of what was defined in the test Fixture. If AGENT_VERSION isn't set, it'll default to the current version without SNAPSHOT.

Setup

One-time setup is required to run any integration and E2E tests. Run mage integration:auth to perform this setup.

Running the tests

The test are run with mage using the integration namespace:

  • mage integration:test to execute all tests under the testing/integration folder. All tests are executed on remote VMs, including those that set Local: true.

  • mage integration:local [testName|all] to execute only those tests under the testing/integration folder that set Local: true. It'll run all the tests if all is passed as argument, or it'll pass [testName] to go test as --run=[testName]. These tests are executed on your local machine.

  • mage integration:single [testName] to execute a single test under the testing/integration folder. Only the selected test will be executed on remote VMs.

  • mage integration:matrix to run all tests on the complete matrix of supported operating systems and architectures of the Elastic Agent.

Selecting specific platform

By default, the runner will deploy to every combination of operating system and architecture that the tests define as supporting. When working on tests and debugging an issue it's better to limit the operating system and architecture to a specific one. This can be done inside a test but requires the test code to be modified. An easier way is available using the TEST_PLATFORMS="linux/amd64" environment variable. This variable can take multiple definitions with a space between, and it can be very specific or not very specific.

  • TEST_PLATFORMS="linux" mage integration:test to execute tests only on Linux using both AMD64 and ARM64.
  • TEST_PLATFORMS="linux/amd64" mage integration:test to execute tests only on Linux AMD64.
  • TEST_PLATFORMS="linux/arm64/ubuntu mage integration:test to execute tests only on Ubuntu ARM64.
  • TEST_PLATFORMS="linux/amd64/ubuntu/20.04 mage integration:test to execute tests only on Ubuntu 20.04 ARM64.
  • TEST_PLATFORMS="windows/amd64/2022 mage integration:test to execute tests only on Windows Server 2022.
  • TEST_PLATFORMS="linux/amd64 windows/amd64/2022 mage integration:test to execute tests on Linux AMD64 and Windows Server 2022.

NOTE: This only filters down the tests based on the platform. It will not execute a tests on a platform unless the test defines as supporting it.

Selecting specific group

By default, the runner will run all test groups. Each group runs on a dedicated machine instance. When working on groups of tests it's better to limit to a specific group of tests instead of running all tests. This can be done by using the TEST_GROUPS="default upgrade-standalone" environment variable. This variable can take multiple groups with a space between.

  • TEST_GROUPS="default" mage integration:test to execute only tests in the "default" group.
  • TEST_GROUPS="default upgrade-standalone" mage integration:test to execute only tests in the "default" or "upgrade-standalone" group.

Passing additional go test flags

When running the tests we can pass additional go test flag using the env variable GOTEST_FLAGS.

These flags are passed also when calculating batches for remote execution of integration tests. This allows for selecting a subset of test in a convenient way (see examples below)

This feature is intended mostly for integration tests debugging/development without the need for new mage targets corresponding to a new set of test flags.

A few examples:

Run a single test with an exact match

We want to run only the test named "TestStandaloneUpgrade" GOTEST_FLAGS="-test.run ^TestStandaloneUpgrade$" mage integration:test

Run a tests matching a partial expression

We want to run any test with "Upgrade" in the name GOTEST_FLAGS="-test.run Upgrade" mage integration:test

Run a single test and signal that we want the short version

We pass a -test.short flag along with the name match GOTEST_FLAGS="-test.run ^TestStandaloneUpgrade$ -test.short" mage integration:test

Run a single test multiple times

We pass a -test.count flag along with the name match GOTEST_FLAGS="-test.run ^TestStandaloneUpgrade$ -test.count 10" mage integration:test

Run specific tests

We pass a -test.run flag along with the names of the tests we want to run in OR GOTEST_FLAGS="-test.run ^(TestStandaloneUpgrade|TestFleetManagedUpgrade)$" mage integration:test

Run Extended Runtime Leak Test

The test framework includes a "long running" test to check for resource leaks and stability. The runtime of the test can be set via the LONG_TEST_RUNTIME environment variable. The test itself can be run via the integration:TestLongRunningAgentForLeaks mage target.

Limitations

Due to the way the parameters are passed to devtools.GoTest the value of the environment variable is split on space, so not all combination of flags and their values may be correctly split.

Cleaning up resources

The test run will keep provisioned resources (instances and stacks) around after the tests have been ran. This allows following mage integration:* commands to re-use the already provisioned resources.

  • mage integration:clean will de-provision the allocated resources and cleanup any local state.

Tests with external dependencies might need more environment variables to be set when running them manually, such as ELASTICSEARCH_HOST, ELASTICSEARCH_USERNAME, ELASTICSEARCH_PASSWORD, KIBANA_HOST, KIBANA_USERNAME, and KIBANA_PASSWORD.

Debugging tests

Manually debugging tests on VMs

Many of the integration tests will install the Elastic-Agent and/or require root to run, which makes it hard to just run them on our work machines, the best way to circumvent that is to debug the tests directly on a VM. mage integration:DeployDebugTools will show a menu to select a VM and then install the common debugging tools: Delve, Mage and Docker. It will also create the ~/elastic-agent folder containing the Git repository (required to package from within the VM) and the last version of the code uploaded to the VM. This allows you to easily build/package the Elastic-Agent from within the VM as well as run any tests.

After deploying the debug tools, mage integrationDeployEnvFile will create a env.sh and copy it to a selected VM, sourcing it will allow you to any test against the Cloud Stack you selected.

Example of how to run a test from within the VM:

## Run a single test
SNAPSHOT=true TEST_PLATFORMS="linux/amd64" mage integration:single TestLogIngestionFleetManaged
## Let's suppose it has failed

## Install DebugTools
mage -v integration:DeployDebugTools

## Generate and deploy env file
mage -v integration:DeployEnvFile

## SSH into the VM
$(mage integration:SSHVM)

## From inside the VM, the test needs root
sudo su
source ./env.sh
cd elastic-agent
## Any flags passed to the test binary go after the '--', they also need to
## include the `test.` prefix if they're for `go test`
TEST_DEFINE_PREFIX=gambiarra dlv test ./testing/integration/ --build-flags="-tags integration" -- -test.v -test.run TestLogIngestionFleetManaged

A Delve trick If you didn't build the Elastic-Agent directly on the machine you're debugging, it is very likely the location of the source code is different, hence delve cannot show you the code it is running. To solve this, once on Delve shell, run: config substitute-path /go/src/github.com/elastic/elastic-agent /home/ubuntu/elastic-agent` where:

  • /go/src/github.com/elastic/elastic-agent is the path annotated in the binary you are debugging (the one Delve shows).
  • /home/ubuntu/elastic-agent is where Delve should read the source code form.

Auto diagnostics retrieval

When an integration test fails the testing fixture will try its best to automatically collect the diagnostic information of the installed Elastic Agent. In the case that diagnostics is collected the test runner will automatically transfer any collected diagnostics from the instance back to the running host. The results of the diagnostic collection are placed in build/diagnostics.

Gather diagnostics manually

In the case that you want to run the integration testing suite and have it gather the diagnostics at the end of every tests you can use the environment variable AGENT_COLLECT_DIAG=true. When that environment variable is defined it will cause the testing fixture to always collect diagnostics before the uninstall in the cleanup step of a test.

Keeping Elastic Agent installed

When the testing fixture installs the Elastic Agent, it will automatically uninstall the Elastic Agent during the cleanup process of the test. In the event that you do not want this to occur, you can disable the auto-uninstallation using the AGENT_KEEP_INSTALLED=true environment variable. If the test succeeds, the agent will be uninstalled regardless of the value of AGENT_KEEP_INSTALLED.

  • AGENT_KEEP_INSTALLED=true mage integration:single [testName]

Run until failure

In the case that you're tracking down a flaky test it is helpful to have it keep running until it fails. The testing suite has this ability built into it. Using the TEST_RUN_UNTIL_FAILURE=true will keep running the testing suite until it reports a failure.

  • TEST_RUN_UNTIL_FAILURE=true mage integration:single [testName]

Manually running the tests

If you want to run the tests manually, skipping the test runner, set the TEST_DEFINE_PREFIX environment variable to any value and run your tests normally with go test. E.g.:

TEST_DEFINE_PREFIX=gambiarra go test -v -tags integration -run TestProxyURL ./testing/integration/

Connecting to VMs and running tests

Connecting to VMs

All VMs (including Windows) support connections via SSH, the framework generates and stores the necessary SSH keys to access the VMs, the easiest way to connect to them is using the SSH command returned by mage integration:SSHVM. It will list the VMs and ask to select one.

On a Unix shell you can run $(mage integration:SSHVM), the menu is printed to stderr and the SSH command to stdout. After selecting the VM you will have shell connected to it.

Credentials for cloud stack/projects

All cloud deployments and projects can be listed with mage integration:listStacks, they can be used to manually connect to Kibana and Elasticsearch.

If you need to manually run tests against any deployments, mage integration:GenerateEnvFile will generate a file called env.sh that exports environment variables for Unix compatible shells, you can load them into your shell by running source ./env.sh.

To easily deploy the credentials to any VM, just run mage integration:DeployEnvFile. A menu will ask for the desired Stack and VM.

Writing tests

Write integration and E2E tests by adding them to the testing/integration folder.

// TODO: Replace with a comprehensive write-up of define.* directives, // environment variables, etc. useful when writing tests. Until then...

Look at existing tests under the testing/integration for examples of how to write tests using the integration and E2E testing framework. Also look at the github.com/elastic/elastic-agent/pkg/testing/define package for the test framework's API and the github.com/elastic/elastic-agent/pkg/testing/tools package for helper utilities.

Test group

Every define.Require must define a Group that it belongs too. Each group is executed on a separate instance with all tests with in the same group executed on the same instance. Placing similar tests in the same group allows those tests to run on its own instance as well as provides a way for a developer to select a specific group of tests with TEST_GROUP="{group-name}".

Grouping tests is another way of spreading out the testing load across multiple instances. The more groups that are defined the more instances will be provisioned to complete all tests. A balance between a small good set of groups is better than a ton of groups each executing a small set of tests, as the time to set up an instance can out weight the benefits of creating another group.

Test namespaces

Every test has access to its own unique namespace (a string value). This namespace can be accessed from the info.Namespace field, where info is the struct value returned from the define.Require(...) call made at the start of the test.

Namespaces should be used whenever test data is being written to or read from a persistent store that's shared across all tests. Most commonly, this store will be the Elasticsearch cluster that Agent components may index their data into. All tests share a single stack deployment and, therefore, a single Elasticsearch cluster as well.

Some examples of where namespaces should be used:

  • When creating a policy in Fleet. The Create Policy and Update Policy APIs takes a namespace parameter.
  • When searching for documents in logs-* or metrics-* data streams. Every document in these data streams has a data_stream.namespace field.

⚠️ Not using namespaces when accessing data in a shared persistent store can cause tests to be flaky.

Alternative Providers

Multipass Instance Provisioner

By default the integration testing suite uses OGC with GKE to provision instances. In the case that you want to use a local VM instead of a remote VM, you can use the Multipass provisioner.

  • INSTANCE_PROVISIONER="multipass" mage integration:test

It is always best to run mage integration:clean before changing the provisioner because the change will not cause already provisioned resources to be replaced with an instance created by a different provisioner.

Troubleshooting Tips

Error: GCE service token missing; run 'mage integration:auth'

If you encounter this error when running mage integration:test, it's because the test runner is unable to create VMs on GCP to execute the tests.

As the error message suggests, run mage integration:auth to resolve this error.

Error: missing required Elastic Agent package builds for integration runner to execute: ...

If you encounter this error when running mage integration:test or mage integration:local, it's because the test runner couldn't find the appropriate Agent packages in the build/distributions folder.

Run mage package with the appropriate value(s) in PLATFORMS, as suggested by the error message, to build the necessary Agent packages first.

If the issue is that the built Agent packages contain -SNAPSHOT in their versions, whereas the package names in the error message do not, either omit SNAPSHOT=true from the mage package command OR set the AGENT_VERSION environment variable to a version that includes the -SNAPSHOT suffix when running mage integration:test or mage integration:local.

Failures on reused resources

The integration framework tries to re-use resource when it can. This improves the speed at which the tests can run, but also means its possible for a failed test to leave state behind that can break future runs.

Run mage integration:clean before running mage integration:test to ensure the tests are being run with fresh instances and stack.

OGC-related errors

If you encounter any errors mentioning ogc, try running mage integration:clean and then re-running whatever mage integration:* target you were trying to run originally when you encountered the error.

Using a different agent version from the stack version

The agent version is used as a fallback for the stack version to use in integration tests if no other version is specified.

If we need to use a different version between agent and stack we can specify the stack version using a separate env variable AGENT_STACK_VERSION like in this example (we used a custom package version for the agent):

AGENT_VERSION="8.10.0-testpkgversion.1-SNAPSHOT" AGENT_STACK_VERSION="8.10.0-SNAPSHOT" mage integration:test