Tenant Configuration

After zuul.conf is configured, Zuul component servers will be able to start, but a tenant configuration is required in order for Zuul to perform any actions. The tenant configuration file specifies upon which projects Zuul should operate. These repositories are grouped into tenants. The configuration of each tenant is separate from the rest (no pipelines, jobs, etc are shared between them).

A project may appear in more than one tenant; this may be useful if you wish to use common job definitions across multiple tenants.

Actions normally available to the Zuul operator only can be performed by specific users on Zuul’s REST API, if admin rules are listed for the tenant. Admin rules are also defined in the tenant configuration file.

The tenant configuration file is specified by the scheduler.tenant_config setting in zuul.conf. It is a YAML file which, like other Zuul configuration files, is a list of configuration objects, though only two types of objects are supported: tenant and admin-rule.

Alternatively the scheduler.tenant_config_script can be the path to an executable that will be executed and its stdout used as the tenant configuration. The executable must return a valid tenant YAML formatted output.

Tenant

A tenant is a collection of projects which share a Zuul configuration. Some examples of tenant definitions are:

- tenant:
    name: my-tenant
    max-nodes-per-job: 5
    exclude-unprotected-branches: false
    source:
      gerrit:
        config-projects:
          - common-config
          - shared-jobs:
              include: job
        untrusted-projects:
          - zuul/zuul-jobs:
              shadow: common-config
          - project1
          - project2:
              exclude-unprotected-branches: true

- tenant:
    name: my-tenant
    admin-rules:
      - acl1
      - acl2
    source:
      gerrit:
        config-projects:
          - common-config
        untrusted-projects:
          - exclude:
              - job
              - semaphore
              - project
              - project-template
              - nodeset
              - secret
            projects:
              - project1
              - project2:
                  exclude-unprotected-branches: true

tenant

The following attributes are supported:

tenant.name (required): The name of the tenant. This may appear in URLs, paths, and monitoring fields, and so should be restricted to URL friendly characters (ASCII letters, numbers, hyphen and underscore) and you should avoid changing it unless necessary.

tenant.source (required): A dictionary of sources to consult for projects. A tenant may contain projects from multiple sources; each of those sources must be listed here, along with the projects it supports. The name of a connection is used as the dictionary key (e.g. gerrit in the example above), and the value is a further dictionary containing the keys below.

The next two attributes, config-projects and untrusted-projects provide the bulk of the information for tenant configuration. They list all of the projects upon which Zuul will act.

The order of the projects listed in a tenant is important. A job which is defined in one project may not be redefined in another project; therefore, once a job appears in one project, a project listed later will be unable to define a job with that name. Further, some aspects of project configuration (such as the merge mode) may only be set on the first appearance of a project definition.

Zuul loads the configuration from all config-projects in the order listed, followed by all untrusted-projects in order.

tenant.config-projects

A list of projects to be treated as config projects in this tenant. The jobs in a config project are trusted, which means they run with extra privileges, do not have their configuration dynamically loaded for proposed changes, and Zuul config files are only searched for in the master branch.

The items in the list follow the same format described in untrusted-projects.

tenant.config-projects.<project>

The config-projects have an additional config option that may be specified optionally.

tenant.config-projects.<project>.load-branch Default: master: Define which branch is loaded from a config project. By default config projects load Zuul configuration only from the master branch.

tenant.untrusted-projects

A list of projects to be treated as untrusted in this tenant. An untrusted-project is the typical project operated on by Zuul. Their jobs run in a more restrictive environment, they may not define pipelines, their configuration dynamically changes in response to proposed changes, and Zuul will read configuration files in all of their branches.

tenant.untrusted-projects.<project>

The items in the list may either be simple string values of the project names, or a dictionary with the project name as key and the following values:

tenant.untrusted-projects.<project>.include

Normally Zuul will load all of the Configuration Items appropriate for the type of project (config or untrusted) in question. However, if you only want to load some items, the include attribute can be used to specify that only the specified items should be loaded. Supplied as a string, or a list of strings.

The following configuration items are recognized:

pipeline
job
semaphore
project
project-template
nodeset
secret

tenant.untrusted-projects.<project>.exclude: A list of configuration items that should not be loaded.

tenant.untrusted-projects.<project>.shadow: A list of projects which this project is permitted to shadow. Normally, only one project in Zuul may contain definitions for a given job. If a project earlier in the configuration defines a job which a later project redefines, the later definition is considered an error and is not permitted. The shadow attribute of a project indicates that job definitions in this project which conflict with the named projects should be ignored, and those in the named project should be used instead. The named projects must still appear earlier in the configuration. In the example above, if a job definition appears in both the common-config and zuul-jobs projects, the definition in common-config will be used.

tenant.untrusted-projects.<project>.exclude-unprotected-branches: Define if unprotected branches should be processed. Defaults to the tenant wide setting of exclude-unprotected-branches. This currently only affects GitHub and GitLab projects.

tenant.untrusted-projects.<project>.extra-config-paths

Normally Zuul loads in-repo configuration from the first of these paths:

zuul.yaml
zuul.d/*
.zuul.yaml
.zuul.d/*

If this option is supplied then, after the normal process completes, Zuul will also load any configuration found in the files or paths supplied here. This can be a string or a list. If a list of multiple items, Zuul will load configuration from all of the items in the list (it will not stop at the first extra configuration found). Directories should be listed with a trailing /. Example:

extra-config-paths:
  - zuul-extra.yaml
  - zuul-extra.d/

This feature may be useful to allow a project that primarily holds shared jobs or roles to include additional in-repo configuration for its own testing (which may not be relevant to other users of the project).

tenant.untrusted-projects.<project-group>

The items in the list are dictionaries with the following attributes. A configuration items definition is applied to the list of projects.

tenant.untrusted-projects.<project-group>.include: A list of configuration items that should be loaded.

tenant.untrusted-projects.<project-group>.exclude: A list of configuration items that should not be loaded.

tenant.untrusted-projects.<project-group>.projects: A list of project items.

tenant.max-nodes-per-job Default: 5: The maximum number of nodes a job can request. A value of ‘-1’ value removes the limit.

tenant.max-job-timeout Default: 10800: The maximum timeout for jobs. A value of ‘-1’ value removes the limit.

tenant.exclude-unprotected-branches Default: false: When using a branch and pull model on a shared repository there are usually one or more protected branches which are gated and a dynamic number of personal/feature branches which are the source for the pull requests. These branches can potentially include broken Zuul config and therefore break the global tenant wide configuration. In order to deal with this Zuul’s operations can be limited to the protected branches which are gated. This is a tenant wide setting and can be overridden per project. This currently only affects GitHub and GitLab projects.

tenant.default-parent Default: base: If a job is defined without an explicit job.parent attribute, this job will be configured as the job’s parent. This allows an administrator to configure a default base job to implement local policies such as node setup and artifact publishing.

tenant.default-ansible-version: Default ansible version to use for jobs that doesn’t specify a version. See job.ansible-version for details.

tenant.allowed-triggers Default: all connections: The list of connections a tenant can trigger from. When set, this setting can be used to restrict what connections a tenant can use as trigger. Without this setting, the tenant can use any connection as a trigger.

tenant.allowed-reporters Default: all connections: The list of connections a tenant can report to. When set, this setting can be used to restrict what connections a tenant can use as reporter. Without this setting, the tenant can report to any connection.

tenant.allowed-labels Default: []: The list of labels (as strings or regular expressions) a tenant can use in a job’s nodeset. When set, this setting can be used to restrict what labels a tenant can use. Without this setting, the tenant can use any labels.

tenant.disallowed-labels Default: []: The list of labels (as strings or regular expressions) a tenant is forbidden to use in a job’s nodeset. When set, this setting can be used to restrict what labels a tenant can use. Without this setting, the tenant can use any labels permitted by tenant.allowed-labels. This check is applied after the check for allowed-labels and may therefore be used to further restrict the set of permitted labels.

tenant.web-root: If this tenant has a whitelabeled installation of zuul-web, set its externally visible URL here (e.g., https://tenant.example.com/). This will override the web.root setting when constructing URLs for this tenant.

tenant.admin-rules

A list of access rules for the tenant. These rules are checked to grant privileged actions to users at the tenant level, through Zuul’s REST API.

At least one rule in the list must match for the user to be allowed the privileged action.

More information on tenant-scoped actions can be found in Tenant Scoped REST API.

Access Rule

An access rule is a set of conditions the claims of a user’s JWT must match in order to be allowed to perform protected actions at a tenant’s level.

The protected actions available at tenant level are autohold, enqueue, dequeue or promote.

Note

Rules can be overridden by the zuul.admin claim in a token if if matches an authenticator configuration where allow_authz_override is set to true. See Zuul web server’s configuration for more details.

Below are some examples of how access rules can be defined:

- admin-rule:
    name: affiliate_or_admin
    conditions:
      - resources_access:
          account:
            roles: "affiliate"
        iss: external_institution
      - resources_access.account.roles: "admin"
- admin-rule:
    name: alice_or_bob
    conditions:
      - zuul_uid: alice
      - zuul_uid: bob

admin-rule

The following attributes are supported:

admin-rule.name (required): The name of the rule, so that it can be referenced in the admin-rules attribute of a tenant’s definition. It must be unique.

admin-rule.conditions (required)

This is the list of conditions that define a rule. A JWT must match at least one of the conditions for the rule to apply. A condition is a dictionary where keys are claims. All the associated values must match the claims in the user’s token; in other words the condition dictionary must be a “sub-dictionary” of the user’s JWT.

Zuul’s authorization engine will adapt matching tests depending on the nature of the claim in the token, eg:

if the claim is a JSON list, check that the condition value is in the claim
if the claim is a string, check that the condition value is equal to the claim’s value

The claim names can also be written in the XPath format for clarity: the condition

resources_access:
  account:
    roles: "affiliate"

is equivalent to the condition

resources_access.account.roles: "affiliate"

The special zuul_uid claim refers to the uid_claim setting in an authenticator’s configuration. By default it refers to the sub claim of a token. For more details see the configuration section for Zuul web server.

Under the above example, the following token would match rules affiliate_or_admin and alice_or_bob:

{
 'iss': 'external_institution',
 'aud': 'my_zuul_deployment',
 'exp': 1234567890,
 'iat': 1234556780,
 'sub': 'alice',
 'resources_access': {
     'account': {
         'roles': ['affiliate', 'other_role']
     }
 },
}

And this token would only match rule affiliate_or_admin:

{
 'iss': 'some_other_institution',
 'aud': 'my_zuul_deployment',
 'exp': 1234567890,
 'sub': 'carol',
 'iat': 1234556780,
 'resources_access': {
     'account': {
         'roles': ['admin', 'other_role']
     }
 },
}

Access Rule Templating

The special word “{tenant.name}” can be used in conditions’ values. It will be automatically substituted for the relevant tenant when evaluating authorizations for a given set of claims. For example, consider the following rule:

- admin-rule:
    name: tenant_in_groups
    conditions:
      - groups: "{tenant.name}"

If applied to the following tenants:

- tenant:
    name: tenant-one
    admin-rules:
      - tenant_in_groups
- tenant:
    name: tenant-two
    admin-rules:
      - tenant_in_groups

Then this set of claims will be allowed to perform protected actions on tenant-one:

{
 'iss': 'some_other_institution',
 'aud': 'my_zuul_deployment',
 'exp': 1234567890,
 'sub': 'carol',
 'iat': 1234556780,
 'groups': ['tenant-one', 'some-other-group'],
}

And this set of claims will be allowed to perform protected actions on tenant-one and tenant-two:

{
 'iss': 'some_other_institution',
 'aud': 'my_zuul_deployment',
 'exp': 1234567890,
 'sub': 'carol',
 'iat': 1234556780,
 'groups': ['tenant-one', 'tenant-two'],
}