zuul-weeder: Zuul configuration analyzer

Use this service to inspect the configurations objects loaded in a zuul system.

Overview and scope

Zuul Weeder analyzes the configuration objects such as jobs and nodesets and provides a search interface for:

• Depencencies: what depends on an object.
• Requirements: what is needed by an object.
• URL of the configuration files that contains the object.

Zuul Weeder leverage a generic dependency graph using the data found in the ZooKeeper database to collect every configuration elements used by any tenants. The goal is to help evaluate the impact of a configuration change, for example, when removing a node label or a repository.

Usage

The service provide two functions:

• /search/$name returns the list of object matching the requested name.
• /object/$type/$name returns
  • the list of configuration file url that directly defines or uses the object,
  • the list of related objects that are reachable, either by requirement or by dependency.

For example, by visiting /search/centos, the service returns:

• job tripleo-centos
• nodeset centos
• label cloud-centos

And by visiting /object/nodeset/centos, the service returns:

• The list of zuul.yaml file url that contains a nodeset named centos.
• The list of jobs and project that depends on this nodeset.
• The list of node label name that is required by this nodeset.

The results can be scoped to a specific tenant by using the /tenant/$tenant url prefix.

Setup

Start the service at http://localhost:9001 (needs access to the zuul.conf):

podman run -p 9001:9001 -v /etc/zuul:/etc/zuul:ro --rm quay.io/software-factory/zuul-weeder

Serve behind a sub-path using this argument -e WEEDER_ROOT_URL=/weeder/ and this httpd.conf:

<Location "/weeder">
    ProxyPass http://weeder-host:9001
    ProxyPassReverse http://weeder-host:9001
</Location>

Setup monitoring by adding this prometheus configuration:

scrape_configs:
  - job_name: weeder
    static_configs:
      - targets:
          - weeder-host:9001

Configure grafana dashboard by running ./bin/create-dashboard

Roadmap

Here are some planned features:

• Add a project name object type, to resolve global project configuration (e.g. with a name regexp) and to create a graph connection for all the matching repository names.
• Connect the graphs from multiple zuul-weeder service to analyse the configuration cross deployments.
• Display the weeds, e.g. the dead configuration object that are unreachable.

Checkout the Developper Guide.