Schema#

The initial step in integrating a device with SDC involves importing the device's schema. SDC is equipped to handle YANG schemas, provided all necessary model files and their respective dependencies are available in a git repository. This process is facilitated through the Schema CustomResource, detailed here.

The Schema CustomResource is configured using three main parameter groups:

Source of Schema: Determined by repoURL, kind, and ref parameters.
Schema Identification: Specified using provider and version parameters.
Schema Parsing Method: Configured through models, includes, and excludes parameters.

Source of Schema: Repository Configuration#

To successfully retrieve the schema, it is essential for users to provide four key parameters: repoURL, kind, ref and credentials. These parameters jointly establish the methodology for schema acquisition:

repoURL: This parameter is pivotal as it specifies the repository's URL where the schema is located.
kind: It determines the nature of the reference point within the repository, offering options between a "tag" or a "branch".
ref: This parameter is closely linked to kind and pinpoints the exact tag or branch name within the repository.
credentials: This parameter is point to a secret name in the same namespace as the schema CR. It is required if your repository requires authentication e.g. a private repo.

Following the identification of schema directories and files for download, the dirs attribute plays a crucial role. It allows users to map each source directory to a corresponding local storage location. Essentially, dirs is an array comprising pairs of src (source directory) and dst (destination path). This setup facilitates the organization of downloaded schema files, ensuring they are stored in designated local directories for easy access and management.

If the dirs attribute is not set, it defaults to $pwd for both src and dst.

Repository authentication#

If your schema repository requires authentication a secret of type kubernetes.io/basic-auth is referenced in the schema CR. An Example of such secret is provided below.

username/password

Please fill out your own username and password/token

namespace

The secret MUST use the same namespace as the schema CR that is referencing it.

apiVersion: v1
kind: Secret
metadata:
  name: personal-access-token
data:
  username: <base64-encoded-username>
  password: <base64-encoded-password>
type: kubernetes.io/basic-auth

Schema Identification: Naming Conventions#

The schema is uniquely identified through provider and version.

provider: Contains details about the schema issuer, typically including vendor and chassis type.
version: Represents the specific version of the schema.

Schema Parsing Method: Handling YANG Models#

YANG schemas are comprised of several implemented models, some of which may have dependencies on other models. The `Schema`` CustomResource accommodates this complexity with specific parameters:

models: Defines paths to files or directories containing the models implemented by the schema.
includes: Specifies paths to models that are imported as dependencies by the implemented models.
excludes: An optional list of regular expression parameters. It filters out specific models during the loading process based on matching criteria.

By carefully setting these parameters, users can seamlessly onboard devices into the SDC framework, ensuring that the schemas are accurately loaded and parsed.

Examples#

SR Linux v23.10.1#

The below CR defines an SR Linux Schema version 23.10.1.

The YANG files will be retrieved from the github repo https://github.com/nokia/srlinux-yang-models tag v23.10.1. The remote directory srlinux-yang-models at the roo level of the git repository will be mapped to $pwd (dst: .) in the local file system

apiVersion: inv.sdcio.dev/v1alpha1
kind: Schema
metadata:
  name: srl.nokia.sdcio.dev-23.10.1
  namespace: default
spec:
  repoURL: https://github.com/nokia/srlinux-yang-models
  provider: srl.nokia.sdcio.dev
  version: 23.10.1
  kind: tag
  ref: v23.10.1
  dirs:
  - src: srlinux-yang-models
    dst: .
  schema:
    models:
    - srl_nokia/models
    includes:
    - ietf
    - openconfig/extensions
    - openconfig/openconfig-extensions.yang
    excludes:
    - .*tools.*

To apply the CR, store the above content in a file (e.g: srlinux_23.10.1_schema.yaml) and run the command:

kubectl apply -f srlinux23.10.1_schema.yaml

After applying the previous CR to a kubernetes cluster, the Schema can be viewed with the commands:

kubectl get schemas.inv.sdcio.dev

kubectl get schemas srl.nokia.sdcio.dev-23.10.1 -o yaml

Sample outputs:

$ kubectl get schemas.inv.sdcio.dev
NAME                           READY   URL                                            REF             PROVIDER               VERSION
srl.nokia.sdcio.dev-23.10.1    True    https://github.com/nokia/srlinux-yang-models   v23.10.1        srl.nokia.sdcio.dev    23.10.1

$ kubectl get schemas srl.nokia.sdcio.dev-23.10.1 -o yaml
apiVersion: inv.sdcio.dev/v1alpha1
kind: Schema
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"inv.sdcio.dev/v1alpha1","kind":"Schema","metadata":{"annotations":{},"name":"srl.nokia.sdcio.dev-23.10.1","namespace":"default"},"spec":{"dirs":[{"dst":".","src":"srlinux-yang-models"}],"kind":"tag","provider":"srl.nokia.sdcio.dev","ref":"v23.10.1","repoURL":"https://github.com/nokia/srlinux-yang-models","schema":{"excludes":[".*tools.*"],"includes":["ietf","openconfig/extensions","openconfig/openconfig-extensions.yang"],"models":["srl_nokia/models"]},"version":"23.10.1"}}
  creationTimestamp: "2024-01-09T23:05:13Z"
  finalizers:
  - schema.inv.sdcio.dev/finalizer
  generation: 1
  name: srl.nokia.sdcio.dev-23.10.1
  namespace: default
  resourceVersion: "872"
  uid: 8b533cc2-38fa-4487-965d-3877beb455fc
spec:
  dirs:
  - dst: .
    src: srlinux-yang-models
  kind: tag
  provider: srl.nokia.sdcio.dev
  ref: v23.10.1
  repoURL: https://github.com/nokia/srlinux-yang-models
  schema:
    excludes:
    - .*tools.*
    includes:
    - ietf
    - openconfig/extensions
    - openconfig/openconfig-extensions.yang
    models:
    - srl_nokia/models
  version: 23.10.1
status:
  conditions:
  - lastTransitionTime: "2024-01-09T23:05:16Z"
    message: ""
    reason: Ready
    status: "True"
    type: Ready

SROS 23.10.2#

apiVersion: inv.sdcio.dev/v1alpha1
kind: Schema
metadata:
  name: sros.nokia.sdcio.dev-23.10.1
  namespace: default
spec:
  repoURL: https://github.com/nokia/7x50_YangModels
  provider: sros.nokia.sdcio.dev
  version: 23.10.2
  kind: tag
  ref: sros_23.10.r2
  dirs:
  - src: YANG
    dst: .
  schema:
    models:
    - nokia-combined
    includes:
    - ietf
    - nokia-sros-yang-extensions.yang
    excludes: []

Juniper MX 23.2R1#

apiVersion: inv.sdcio.dev/v1alpha1
kind: Schema
metadata:
  name: mx.juniper.23.2r1
  namespace: default
spec:
  repoURL: https://github.com/Juniper/yang
  provider: mx.juniper.sdcio.dev
  version: 23.2R1
  kind: branch
  ref: master
  dirs:
  - src: 23.2/23.2R1/junos/conf
    dst: junos
  - src: 23.2/23.2R1/common
    dst: common
  schema:
    models:
    - junos
    includes:
    - common

Juniper QFX 23.2R1#

apiVersion: inv.sdcio.dev/v1alpha1
kind: Schema
metadata:
  name: qfx.juniper.23.2r1
  namespace: default
spec:
  repoURL: https://github.com/Juniper/yang
  provider: qfx.juniper.sdcio.dev
  version: 23.2R1
  kind: branch
  ref: master
  dirs:
  - src: 23.2/23.2R1/junos-qfx/conf
    dst: junos
  - src: 23.2/23.2R1/common
    dst: common
  schema:
    models:
    - junos
    includes:
    - common

Juniper EX 23.2R1#

apiVersion: inv.sdcio.dev/v1alpha1
kind: Schema
metadata:
  name: ex.juniper.23.2r1
  namespace: default
spec:
  repoURL: https://github.com/Juniper/yang
  provider: ex.juniper.sdcio.dev
  version: 23.2R1
  kind: branch
  ref: master
  dirs:
  - src: 23.2/23.2R1/junos-ex/conf
    dst: junos
  - src: 23.2/23.2R1/common
    dst: common
  schema:
    models:
    - junos
    includes:
    - common

Juniper NFX 23.2R1#

apiVersion: inv.sdcio.dev/v1alpha1
kind: Schema
metadata:
  name: nfx.juniper.23.2r1
  namespace: default
spec:
  repoURL: https://github.com/Juniper/yang
  provider: nfx.juniper.sdcio.dev
  version: 23.2R1
  kind: branch
  ref: master
  dirs:
  - src: 23.2/23.2R1/junos-nfx/conf
    dst: junos
  - src: 23.2/23.2R1/common
    dst: common
  schema:
    models:
    - junos
    includes:
    - common