Cincinnati is an update protocol designed to facilitate automatic updates. It describes a particular method for representing transitions between releases of a project and allowing a client to perform automatic updates between these releases.

Quick Start

Prepare custom environment variables

# Please change these accordingly
export CINCINNATI_REGISTRY="https://quay.io"
export CINCINNATI_REPO="openshift-ota/openshift-cincinnati-test-public-manual"

See the details about pushing images to the above repo.

cargo run --package graph-builder -- --service.address 0.0.0.0 --upstream.registry.url "${CINCINNATI_REGISTRY}" --upstream.registry.repository "${CINCINNATI_REPO}" &
cargo run --package policy-engine -- --service.address 0.0.0.0 &
 curl -s 'Accept:application/json' http://localhost:8081/graph\?channel\=candidate-4.18 | jq
{
  "version": 1,
  "nodes": [
    {
      "version": "4.18.3",
      "payload": "quay.io/openshift-ota/openshift-cincinnati-test-public-manual@sha256:fdcb3da3a1086d664df31a1fa2a629c77780f844d458af956928cca297da343c",
      "metadata": {
        "io.openshift.upgrades.graph.release.manifestref": "sha256:fdcb3da3a1086d664df31a1fa2a629c77780f844d458af956928cca297da343c",
        "io.openshift.upgrades.graph.release.channels": "candidate-4.18,eus-4.18,fast-4.18,stable-4.18,candidate-4.19",
        "io.openshift.upgrades.graph.previous.remove_regex": ".*|4[.]17[.].*|4[.](17[.](1[01]|0-.*|[0-9])|18.0-(ec[.].*|rc[.][0-3]))",
        "url": "https://access.redhat.com/errata/RHBA-2025:2229"
      }
    }
  ],
  "edges": [],
  "conditionalEdges": []
}

Note: the default configuration of the policy-engine requires the channel parameter to be present in each request.

Tests

There are several ways of testing various parts of the Cincinnati stack.

The language-level tests can be run using cargo --test in the repository's root directory:

cargo test

The online tests for the graph-builder depend on a curated set of repositories to be available on quay.io in the redhat organization. The build instructions for (re-)populating the repositories are available at graph-builder/tests/images/build-n-push.sh. The script must run be run from its directory to function:

cd graph-builder/tests/images
./build-n-push.sh test-*

The graph-builder package currently has network dependent tests which gated behind the feature test-net and test-net-private. The latter requires setting the environment variable CINCINNATI_TEST_CREDENTIALS_PATH which is equivalent to graph-builder's --credentials-path.

Assuming you have access to images under the quay.io/redhat organization, and have an appropriate $HOME/.docker/config.json in place, this might work on your machine:

cd graph-builder
export CINCINNATI_TEST_CREDENTIALS_PATH="$HOME/.docker/config.json"
cargo test --features test-net,test-net-private

The dist/ directory contains various CI/CD related files.

• Uses dist/Dockerfile.build/Dockerfile as the build container image
• Run the following scripts on PR
  • dist/prow_yaml_lint.sh
  • dist/prow_rustfmt.sh
  • dist/cargo_test.sh

For details please see github.com/openshift/release/(...)/openshift-cincinnati-master.yaml.

• Uses dist/Dockerfile.build/Dockerfile as the build container image
• Runs dist/build_deploy.sh for successful merges to the master branch and pushes the result to the staging environment (URL is not yet publicly available)

Development

For developing Cincinnati refer to the developer documentation document.

The interface for external plugins is defined as a Protobuf v3 scheme in the file [cincinnati/src/plugins/interface.proto][./cincinnati/src/plugins/interface.proto]. In order to regenerate the files the cincinnati crate must be built with the codegen-protoc feature:

cd cincinnati
cargo build --features=codegen-protoc

The CI/CD system doesn't do this and it relies on the generated code being committed to the repository; please do so after generating new code!