Fprime Component Integration Test

Skill: F Prime Reusable Component Integration Testing

Reusable integration tests live in the component's own test/int/ folder and verify that the component works correctly in a running deployment. They exercise the component through the Ground Data System (GDS) — sending commands, checking events, and reading telemetry over the actual communication stack.

For the full implementation guide, see Reusable Integration Tests. For the complete API reference (send commands, assert events/telemetry, predicates, histories), see the GDS Integration Test API Guide.

Note: This skill covers component-level reusable integration tests. System-wide integration tests (testing cross-component workflows across an entire deployment) are a separate concern.

Prerequisites

The component must be added to a topology before integration tests can run. If it has not been integrated yet, see docs/user-manual/overview/development-practice.md § "Assemble Topology".

The deployment must be running (via fprime-gds) for integration tests to execute.

Process

Step 1 — Set Up Test Directory

Create test/int/test_<ComponentName>.py in the component folder. See Reusable Integration Tests for the expected file layout and int_config.json configuration.

Step 2 — Write Reusable Tests

Tests use pytest with the fprime_test_api fixture. Use fprime_test_api.get_mnemonic() to resolve instance names from a configuration file, making tests portable across deployments. See the GDS Test API Guide for the full API (sending commands, asserting events/telemetry, predicates, sequences).

Key patterns:

• send_and_assert_command() — send + verify command success events
• assert_event() / assert_telemetry() — verify component output
• get_mnemonic() — resolve qualified names for portability
• Map each test to a requirement in the docstring (Covers: REQ-*)

Step 3 — Draft Requirements Coverage

Draft which requirements should be covered by integration tests. Aim for reasonable coverage of the component's requirements, especially those that exercise inter-component behavior.

Step 4 — Run Integration Tests

# Start the deployment + GDS (in separate terminal)
fprime-gds --dictionary <path-to-dictionary>

# Run the component's reusable tests against a deployment
pytest <Component>/test/int/ \
       --dictionary <path-to-dictionary> \
       --deployment-config <path>/int_config.json

See Reusable Integration Tests § Running the tests for CI integration using fprime-actions/run-integration-tests.

Anti-Patterns

• Hardcoding instance mnemonics — use get_mnemonic() for portability
• Writing tests that depend on test execution order
• Ignoring max_delay / timeout (tests will hang or be flaky)
• Not mapping tests to requirements
• Testing unit-level behavior in integration tests (use unit tests for that)