PVF Host

This is the PVF host, responsible for responding to requests from Candidate Validation and spawning worker tasks to fulfill those requests.

See also:

• for more information: the Implementer's Guide
• for an explanation of terminology: the Glossary

Running basic tests

Running cargo test in the pvf/ directory will run unit and integration tests.

Note: some tests run only under Linux, x86-64, and/or with the ci-only-tests feature enabled.

See the general Testing instructions for more information on running tests and observing logs.

Running a test-network with zombienet

Since this crate is consensus-critical, for major changes it is highly recommended to run a test-network. See the "Behavior tests" section of the Testing docs for full instructions.

To run the PVF-specific zombienet test:

RUST_LOG=parachain::pvf=trace zombienet --provider=native spawn zombienet_tests/functional/0001-parachains-pvf.toml

Testing on Linux

Some of the PVF functionality, especially related to security, is Linux-only, and some is x86-64-only. If you touch anything security-related, make sure to test on Linux x86-64! If you're on a Mac, you can either run a VM or you can hire a VPS and use the open-source tool EternalTerminal to connect to it.[^et]

[^et]: Unlike ssh, ET preserves your session across disconnects, and unlike another popular persistent shell, mosh, it allows scrollback.