[feature request] Add `--namespace` and `--generate-namespace` flags for `score-k8s generate`

[mathieu-benoit]

Context: feedback and feature request captured thanks to this blog post, thanks Artem!

In order to better support the management and assignment of Namespace on Manifests generated or patched by score-k8s generate, we need to add the --namespace and --generate-namespace flags for score-k8s generate.

Like helm install|upgrade works.

• --namespace (optional) will set the metadata.namespace field if supplied
• --generate-namespace (optional) will actually add a default Namespace manifest in the generated manifests.yaml, --namespace will be required in this case.

We also need to think about how this --namespace value is passed through/to the provisioners and patch-templates for them to set the value if supplied.

Note: if someone wants to patch the generated Namespace, they will be able to use a patch-templates to inject annotations, labels, etc.

Implementation details:

• Feat: Add --namespace and --generate-namespace flags for score-k8s generate #176
• namespace passed through the --patch-templates #183
• Support --namespace with service-account with score-k8s 0.5.2 community-patchers#17
• namespace-pss-restricted community-patchers#18
• CLI: --namespace and --generate-namespace docs#191
• Support of --namespace for provisioners #187
• Support score-k8s's --namespace community-provisioners#40
• Take into account .Namespace in default provisioners #190

[yanurag-dev]

@mathieu-benoit I would like to pick this issue.

[mathieu-benoit]

Sure thing, @Yadavanurag13, thank you!

Please do let us know if you have any questions or need any clarification!

[yanurag-dev]

@mathieu-benoit Sure. I'll go through more deeply and let u know.

[mathieu-benoit]

@Yadavanurag13, I meant to share more context and guidance about the success criterias for what could be a good first PR to tackle most of this feature request (we will see if the rest will be in a second PR or in this one later).

After an initial score-k8s init, top of mind, here are 5 main use cases/unit tests.

1. First, this should still work (validating that these new parameters are optional, not changing the current behavior):

score-k8s generate score.yaml

INFO: Added score file to project
INFO: Primed resources
INFO: Loaded provisioners
INFO: Persisted state file
INFO: Wrote 2 manifests to manifests buffer for workload 'example'
INFO: Wrote manifests to 'manifests.yaml'

cat manifests.yaml

---
apiVersion: v1
kind: Service
metadata:
    annotations:
        k8s.score.dev/workload-name: example
    creationTimestamp: null
    labels:
        app.kubernetes.io/instance: example-b71317f5bf
        app.kubernetes.io/managed-by: score-k8s
        app.kubernetes.io/name: example
    name: example
spec:
    ports:
        - name: web
          port: 8080
          protocol: TCP
          targetPort: 8080
    selector:
        app.kubernetes.io/instance: example-b71317f5bf
status:
    loadBalancer: {}
---
apiVersion: apps/v1
kind: Deployment
metadata:
    annotations:
        k8s.score.dev/workload-name: example
    creationTimestamp: null
    labels:
        app.kubernetes.io/instance: example-b71317f5bf
        app.kubernetes.io/managed-by: score-k8s
        app.kubernetes.io/name: example
    name: example
spec:
    selector:
        matchLabels:
            app.kubernetes.io/instance: example-b71317f5bf
    strategy: {}
    template:
        metadata:
            annotations:
                k8s.score.dev/workload-name: example
            creationTimestamp: null
            labels:
                app.kubernetes.io/instance: example-b71317f5bf
                app.kubernetes.io/managed-by: score-k8s
                app.kubernetes.io/name: example
        spec:
            containers:
                - image: stefanprodan/podinfo
                  name: main
                  resources: {}
status: {}

2. Second, using --namespace test-ns should do this:

score-k8s generate score.yaml --namespace test-ns

INFO: Added score file to project
INFO: Primed resources
INFO: Loaded provisioners
INFO: Persisted state file
INFO: Wrote 2 manifests to manifests buffer for workload 'example'
INFO: Wrote manifests to 'manifests.yaml'

cat manifests.yaml

---
apiVersion: v1
kind: Service
metadata:
    annotations:
        k8s.score.dev/workload-name: example
    creationTimestamp: null
    labels:
        app.kubernetes.io/instance: example-b71317f5bf
        app.kubernetes.io/managed-by: score-k8s
        app.kubernetes.io/name: example
    name: example
+  namespace: test-ns
spec:
    ports:
        - name: web
          port: 8080
          protocol: TCP
          targetPort: 8080
    selector:
        app.kubernetes.io/instance: example-b71317f5bf
status:
    loadBalancer: {}
---
apiVersion: apps/v1
kind: Deployment
metadata:
    annotations:
        k8s.score.dev/workload-name: example
    creationTimestamp: null
    labels:
        app.kubernetes.io/instance: example-b71317f5bf
        app.kubernetes.io/managed-by: score-k8s
        app.kubernetes.io/name: example
    name: example
+  namespace: test-ns
spec:
    selector:
        matchLabels:
            app.kubernetes.io/instance: example-b71317f5bf
    strategy: {}
    template:
        metadata:
            annotations:
                k8s.score.dev/workload-name: example
            creationTimestamp: null
            labels:
                app.kubernetes.io/instance: example-b71317f5bf
                app.kubernetes.io/managed-by: score-k8s
                app.kubernetes.io/name: example
        spec:
            containers:
                - image: stefanprodan/podinfo
                  name: main
                  resources: {}
status: {}

3. Third, using --namespace test-ns --generate-namespace should do this:

score-k8s generate score.yaml --namespace test-ns --generate-namespace

INFO: Added score file to project
INFO: Primed resources
INFO: Loaded provisioners
INFO: Persisted state file
- INFO: Wrote 2 manifests to manifests buffer for workload 'example'
+ INFO: Wrote 3 manifests to manifests buffer for workload 'example'
INFO: Wrote manifests to 'manifests.yaml'

cat manifests.yaml

+ ---
+ apiVersion: v1
+ kind: Namespace
+ metadata:
+   labels:
+     app.kubernetes.io/managed-by: score-k8s
+   name: test-ns
---
apiVersion: v1
kind: Service
metadata:
    annotations:
        k8s.score.dev/workload-name: example
    creationTimestamp: null
    labels:
        app.kubernetes.io/instance: example-b71317f5bf
        app.kubernetes.io/managed-by: score-k8s
        app.kubernetes.io/name: example
    name: example
+  namespace: test-ns
spec:
    ports:
        - name: web
          port: 8080
          protocol: TCP
          targetPort: 8080
    selector:
        app.kubernetes.io/instance: example-b71317f5bf
status:
    loadBalancer: {}
---
apiVersion: apps/v1
kind: Deployment
metadata:
    annotations:
        k8s.score.dev/workload-name: example
    creationTimestamp: null
    labels:
        app.kubernetes.io/instance: example-b71317f5bf
        app.kubernetes.io/managed-by: score-k8s
        app.kubernetes.io/name: example
    name: example
+  namespace: test-ns
spec:
    selector:
        matchLabels:
            app.kubernetes.io/instance: example-b71317f5bf
    strategy: {}
    template:
        metadata:
            annotations:
                k8s.score.dev/workload-name: example
            creationTimestamp: null
            labels:
                app.kubernetes.io/instance: example-b71317f5bf
                app.kubernetes.io/managed-by: score-k8s
                app.kubernetes.io/name: example
        spec:
            containers:
                - image: stefanprodan/podinfo
                  name: main
                  resources: {}
status: {}

4. Fourth, using --generate-namespace (without --namespace) should do this:

score-k8s generate score.yaml --generate-namespace

Error: failed to convert 'score.yaml' because --create-namespace was used but --namespace was not provided

5. Fifth, using --help should do this:

score-k8s generate --help

--> This needs to add a documentation about the two new parameters --namespace and --generate-namespace.

The idea in this first PR is to implement this and add the associated unit tests please. We may have missed some aspects around that, so please if you have any doubt or need clarification, again, please do let us know, it will be our pleasure to support you on this.

Thanks again for raising your hand for this one, this is an important feature reported by the end-users of this CNCF Sandbox project, so your contribution will have a huge impact out there!

[yanurag-dev]

Thanks @mathieu-benoit for this context. It will be helpful.

[mathieu-benoit]

Hi @Yadavanurag13, is there anything we can help you with to get started on this? Just making sure you have all the information needed ;)

[yanurag-dev]

Hello @mathieu-benoit. I have started with that, made code changes but there are some test failure and actually I was busy with my exam, Hopefully in this weekend I'll raise PR.