Using Quickstart for Development

TripleO-Quickstart is capable of building a working deployment that incorporates several upstream changes both for the undercloud and the overcloud. The only requirement is for the project to be buildable by DLRN.

We will refer to working with the latest upstream master image and optionally injecting pending changes as devmode.

Quickstart’s third party CI is using ci-scipts/full-deploy.sh, however the invocation is not user friendly. The devmode can be accessed by running:

./devmode.sh <virthost>

Available options:

  • --config <type>: the configuration to deploy, can be minimal, ha or any other node configuration type file from tripleo-quickstart/config/general_config
  • --no-gate: by default the script tries to recreate an environment with an upstream change and asks interactive questions to specify it; this option suppreses that function and creates the environment without any extra changes
  • --working-dir <dir>: directory where all the temporary run time files are stored.
  • virthost: the machine to deploy the environment to

The devmode.sh script uses the master-tripleo-ci release which in turn uses the upstream overcloud images that are also being used for the CI jobs.

If the --no-gate option is absent, the script checks if some environment variables are present, and asks for user input if undefined. The following sections include a detailed explanation of each variable and the process of building and injecting changes.

Gerrit mode

Use the Gerrit mode to have a change and its “Depends-On:” dependencies resolved and built. Detailed description about “Depends-On:” is in the Adding a Dependency and Cross-Repository Dependencies section of the OpenStack Developer’s Guide.

The interactive script will ask for the following variables:

  • GERRIT_HOST: Any of the common gerrit servers. The choices are restricted in the gating role by the ALLOWED_HOSTS list.
  • GERRIT_CHANGE_ID: The long Change-Id from the commit message, starting with I…..
  • GERRIT_BRANCH: The branch of the change.
  • GERRIT_PATCHSET_REVISION: The git hash of the target patchset. Needs to be an exact hash, we can’t determine the latest yet during runtime.

Note

As there can be multiple changes on different branches with the same Change-Id, specifying the branch is mandatory. It’s possible in the future an enhancement could be made to allow for a just-in-time check for a unique Change-Id, thereby allowing us to skip this configuration option.

Zuul mode

The devmode.sh script can be used with a ZUUL_CHANGES variable that can be found in the logs of the upstream CI jobs in the _zuul_ansible/vars.yaml file. The variable contains the gated change and all the dependent changes that Zuul processed and resolved.

An example of the variable looks like this:

ZUUL_CHANGES=openstack/tripleo-heat-templates:master:refs/changes/88/296488/1^openstack/instack-undercloud:master:refs/changes/84/315184/5

Changes are separated by ^ and are in the format of project:branch:refspec, a combination which uniquely identifies a Gerrit change. You can construct your own ZUUL_CHANGES variable if you want to test multiple changes that are not properly linked by “Depends-On:” conditions in the commit messages.

Note

While Zuul only supports “Depends-On:” on the same Gerrit instance, the gating role can resolve changes across these different allowed servers if you specify part of their name after the Change-Id. For example Depends-On: I.....@gerrithub will make your change depend on the specified change from review.gerrithub.io.

Virthost and Workspace

Apart from the variables in either Zuul or Gerrit mode, the script needs a virthost as the first regular argument to build the environment.

Note

You need to be able to ssh into this machine as root without password.

The script uses ~/.quickstart as the default working directory. We store the various run-time files needed for the deployment and accessing the nodes. See Accessing the Undercloud and Accessing the Overcloud for the details.

It’s possible to have more than one parallel working deployment by specifying different virthosts and working directories for each run.

How Devmode Works

The following steps taken by the gates/reproducers compared to a normal quickstart run:

  1. Build RPMs using DLRN from the specified upstream or packaging changes. The changes can be specified either manually or parsed by either environment variables set by Zuul or Jenkins jobs.
  2. Create a gating repository that include all the RPMs built.
  3. Inject a gating repo during the quickstart run into the undercloud and overcloud images.
  4. Upgrade all packages that are inside the gating repo.
  5. Proceed with the quickstart run as usual.

Detailed Package Build and Injection Process

As the devmode bits are dispersed in the code, the exact process is best understood by looking at the relevant parts of the build-test-packages role and various quickstart roles for each step:

  1. Setting up DLRN and parsing the Jenkins/Zuul changes and building the gating repo: build-test-packages role.
  2. Build individual changes based on the parsed data: dlrn-build.yml
  3. Injecting the repo is triggered when compressed_gating_repo is set during the libvirt/setup role.
  4. The repo injection steps are in inject_gating_repo.yml
  5. Creating the repo file and updating the packages are done through the virt-customize command, running inject_gating_repo.sh.