documentation added for pipelines (#2793)

* scaffolding for pipelines

* added rbac for view pipelines

* just an intro added

* adding getting started for pipelines

* changed to podinfo02

* added pipeline spec as flux docs

* pipelines moved into enterprise

* reviewed links

* reviewed rbac

* fixed broken link

* Update website/docs/enterprise/pipelines/getting-started.mdx

Co-authored-by: Yiannis <[email protected]>

* Update website/docs/enterprise/pipelines/getting-started.mdx

Co-authored-by: Yiannis <[email protected]>

* Update website/docs/enterprise/pipelines/getting-started.mdx

Co-authored-by: Yiannis <[email protected]>

* Update website/docs/enterprise/pipelines/intro.mdx

Co-authored-by: Yiannis <[email protected]>

* Update website/docs/enterprise/pipelines/getting-started.mdx

Co-authored-by: Yiannis <[email protected]>

* Update website/docs/enterprise/pipelines/getting-started.mdx

Co-authored-by: Yiannis <[email protected]>

* Update website/docs/enterprise/pipelines/getting-started.mdx

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* Update website/docs/enterprise/pipelines/spec/v1alpha1/pipeline.mdx

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* Update website/docs/enterprise/pipelines/intro.mdx

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* removed not wrapped

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website/docs/enterprise/pipelines/_category_.json

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+{
+  "label": "Pipelines",
+  "position": 3
+}

website/docs/enterprise/pipelines/authorization.mdx

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+---
+title: Authorization
+sidebar_position: 2
+hide_title: true
+---
+
+import TierLabel from "../../_components/TierLabel";
+
+import CodeBlock from "@theme/CodeBlock";
+import BrowserOnly from "@docusaurus/BrowserOnly";
+
+# Authorization  <TierLabel tiers="enterprise" />
+
+This section provides a recommended way to configure RBAC in the context of pipelines. It is oriented to the journey
+that you expect your users to have.
+
+## View pipelines
+
+In order to view pipelines, users would need to have read access to the `pipeline` resource and the underlying `application` resources.
+
+An example of configuration to achieve this purpose could be seen below with `pipeline-reader` role and `search-pipeline-reader`
+role-binding to allow a group `search-developer` to access pipeline resources within `search` namespace.
+
+```yaml
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRole
+metadata:
+  name: pipeline-reader
+rules:
+  - apiGroups: [ "pipelines.weave.works" ]
+    resources: [ "pipelines" ]
+    verbs: [ "get", "list", "watch"]
+  - apiGroups: ["helm.toolkit.fluxcd.io"]
+    resources: [ "helmreleases" ]
+    verbs: [ "get", "list", "watch"]
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: RoleBinding
+metadata:
+  name: search-pipeline-reader
+  namespace: search
+subjects:
+  - kind: Group
+    name: search-developer
+    apiGroup: rbac.authorization.k8s.io
+roleRef:
+  kind: ClusterRole
+  name: pipeline-reader
+  apiGroup: rbac.authorization.k8s.io
+```

website/docs/enterprise/pipelines/getting-started.mdx

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+---
+title: Getting started
+sidebar_position: 1
+hide_title: true
+---
+
+import TierLabel from "../../_components/TierLabel";
+
+import CodeBlock from "@theme/CodeBlock";
+import BrowserOnly from "@docusaurus/BrowserOnly";
+
+# Getting started with pipelines <TierLabel tiers="enterprise" />
+
+## Requirements
+- You have configured Weave GitOps Enterprise [RBAC for pipelines](../authorization)
+
+## Define a pipeline
+
+A pipeline allows you to define the route your application is taking in order to make it to production.
+There are three main concepts playing in a pipeline:
+- the `application` to deliver
+- the `environments` that your app will go through in its way to production (general)
+- the `deployment targets` or the clusters that each environment has
+
+You can define a delivery pipeline using a `Pipeline` custom resource.
+An example of how it looks for an application `podinfo` is shown below.
+
+```yaml
+apiVersion: pipelines.weave.works/v1alpha1
+kind: Pipeline
+metadata:
+  name: podinfo-02
+  namespace: default
+spec:
+  appRef:
+    apiVersion: helm.toolkit.fluxcd.io/v2beta1
+    kind: HelmRelease
+    name: podinfo
+  environments:
+    - name: dev
+      targets:
+        - namespace: podinfo-02-dev
+          clusterRef:
+            kind: GitopsCluster
+            name: dev
+            namespace: flux-system
+    - name: test
+      targets:
+        - namespace: podinfo-02-qa
+          clusterRef:
+            kind: GitopsCluster
+            name: dev
+            namespace: flux-system
+        - namespace: podinfo-02-perf
+          clusterRef:
+            kind: GitopsCluster
+            name: dev
+            namespace: flux-system
+    - name: prod
+      targets:
+        - namespace: podinfo-02-prod
+          clusterRef:
+            kind: GitopsCluster
+            name: prod
+            namespace: flux-system
+```
+
+In the previous example, `podinfo` application is delivered to a traditional pipeline composed by `dev`, `qa`, `perf` and `production` environments.
+Each environment is backed by a `GitopsCluster` [deployment target](../../../cluster-management/managing-existing-clusters/).
+
+For more details about the spec of a pipeline [see here](spec/v1alpha1/pipeline.mdx)
+
+## View the list of pipelines
+
+Once flux has created your pipeline you can navigate to the pipelines view to see it.
+
+![view pipelines](img/view-pipelines.png)
+
+Pipeline list view show the list of pipelines you have access to. For each pipeline, a simplified view of the pipeline
+is shown with the application `Type` and `Environments` it goes through.
+
+## View the details of a pipeline
+
+Once you have selected a pipeline from the list, you will navigate to its details view.
+In pipeline details view you could view the current status of your application by environment and deployment
+target.
+
+![view pipeline details](img/view-pipeline-details.png)
+

website/docs/enterprise/pipelines/intro.mdx

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+---
+title: Introduction
+sidebar_position: 0
+hide_title: true
+---
+
+import TierLabel from "../../_components/TierLabel";
+
+<h1>
+  {frontMatter.title} <TierLabel tiers="Enterprise" />
+</h1>
+
+## Pipelines
+
+As [wikipedia defines](https://en.wikipedia.org/wiki/Continuous_delivery), Continuous delivery is
+
+>a software engineering approach in which teams produce software in short cycles,
+>ensuring that the software can be reliably released at any time and, when releasing the software, without doing so manually.
+>It aims at building, testing, and releasing software with greater speed and frequency.
+
+>Continuous delivery is enabled through the deployment pipeline.
+>The purpose of the deployment pipeline has three components: visibility, feedback, and continually deploy.[12]
+
+Weave Gitops Enterprise Pipelines allows you to define your deployment pipelines to enable continuous delivery for
+your gitops applications.
+
+As part of Weave GitOps Enterprise, you can
+
+- [Define a delivery pipeline](../getting-started/#define-a-pipeline) that you want you application to follow
+- [View a pipeline](../getting-started/#view-pipeline-list) and check the status of your deployments.
+
+Now that you know what delivery pipelines can do for you, follow the [guide to get started](../getting-started).

website/docs/enterprise/pipelines/spec/_category_.json

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+{
+  "label": "Reference",
+  "position": 2
+}

website/docs/enterprise/pipelines/spec/v1alpha1/pipeline.mdx

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+---
+title: Pipeline
+sidebar_position: 1
+hide_title: true
+---
+# Pipeline <TierLabel tiers="enterprise" />
+
+The Pipeline API defines a resource for continuous delivery pipelines.
+
+An example of a fully defined pipeline is shown below.
+
+```yaml
+apiVersion: pipelines.weave.works/v1alpha1
+kind: Pipeline
+metadata:
+  name: podinfo-02
+  namespace: default
+spec:
+  appRef:
+    apiVersion: helm.toolkit.fluxcd.io/v2beta1
+    kind: HelmRelease
+    name: podinfo
+  environments:
+    - name: dev
+      targets:
+        - namespace: podinfo-02-dev
+          clusterRef:
+            kind: GitopsCluster
+            name: dev
+            namespace: flux-system
+    - name: test
+      targets:
+        - namespace: podinfo-02-qa
+          clusterRef:
+            kind: GitopsCluster
+            name: dev
+            namespace: flux-system
+        - namespace: podinfo-02-perf
+          clusterRef:
+            kind: GitopsCluster
+            name: dev
+            namespace: flux-system
+    - name: prod
+      targets:
+        - namespace: podinfo-02-prod
+          clusterRef:
+            kind: GitopsCluster
+            name: prod
+            namespace: flux-system
+```
+
+## Specification
+
+The documentation for version `v1alpha1`  of a `Pipeline` resource is found next.
+
+### Pipeline
+
+
+```go
+// Pipeline is the Schema for the pipelines API
+type Pipeline struct {
+	metav1.TypeMeta   `json:",inline"`
+	metav1.ObjectMeta `json:"metadata,omitempty"`
+
+	Spec PipelineSpec `json:"spec,omitempty"`
+	// +kubebuilder:default={"observedGeneration":-1}
+	Status PipelineStatus `json:"status,omitempty"`
+}
+
+type PipelineSpec struct {
+	// Environments is a list of environments to which the pipeline's application is supposed to be deployed.
+	// +required
+	Environments []Environment `json:"environments"`
+	// AppRef denotes the name and type of the application that's governed by the pipeline.
+	// +required
+	AppRef LocalAppReference `json:"appRef"`
+}
+
+type Environment struct {
+	// Name defines the name of this environment. This is commonly something such as "dev" or "prod".
+	// +required
+	Name string `json:"name"`
+	// Targets is a list of targets that are part of this environment. Each environment should have
+	// at least one target.
+	// +required
+	Targets []Target `json:"targets"`
+}
+
+type Target struct {
+	// Namespace denotes the namespace of this target on the referenced cluster. This is where
+	// the app pointed to by the environment's `appRef` is searched.
+	// +required
+	Namespace string `json:"namespace"`
+	// ClusterRef points to the cluster that's targeted by this target. If this field is not set, then the target is assumed
+	// to point to a Namespace on the cluster that the Pipeline resources resides on (i.e. a local target).
+	// +optional
+	ClusterRef *CrossNamespaceClusterReference `json:"clusterRef,omitempty"`
+}
+
+```
+
+### References
+
+```go
+// LocalAppReference is used together with a Target to find a single instance of an application on a certain cluster.
+type LocalAppReference struct {
+	// API version of the referent.
+	// +required
+	APIVersion string `json:"apiVersion"`
+
+	// Kind of the referent.
+	// +required
+	Kind string `json:"kind"`
+
+	// Name of the referent.
+	// +required
+	Name string `json:"name"`
+}
+
+// CrossNamespaceClusterReference contains enough information to let you locate the
+// typed Kubernetes resource object at cluster level.
+type CrossNamespaceClusterReference struct {
+	// API version of the referent.
+	// +optional
+	APIVersion string `json:"apiVersion,omitempty"`
+
+	// Kind of the referent.
+	// +required
+	Kind string `json:"kind"`
+
+	// Name of the referent.
+	// +required
+	Name string `json:"name"`
+
+	// Namespace of the referent, defaults to the namespace of the Kubernetes resource object that contains the reference.
+	// +optional
+	Namespace string `json:"namespace,omitempty"`
+}
+```
+
+### Status
+
+```go
+type PipelineStatus struct {
+	// ObservedGeneration is the last observed generation.
+	// +optional
+	ObservedGeneration int64 `json:"observedGeneration,omitempty"`
+
+	// Conditions holds the conditions for the Pipeline.
+	// +optional
+	Conditions []metav1.Condition `json:"conditions,omitempty"`
+}
+```
+
+#### Condition Reasons
+```go
+// Reasons are provided as utility, and are not part of the declarative API.
+const (
+	// TargetClusterNotFoundReason signals a failure to locate a cluster resource on the management cluster.
+	TargetClusterNotFoundReason string = "TargetClusterNotFound"
+	// TargetClusterNotReadyReason signals that a cluster pointed to by a Pipeline is not ready.
+	TargetClusterNotReadyReason string = "TargetClusterNotReady"
+	// ReconciliationSucceededReason signals that a Pipeline has been successfully reconciled.
+	ReconciliationSucceededReason string = "ReconciliationSucceeded"
+)
+```
+

website/docs/enterprise/releases.mdx

@@ -1,6 +1,6 @@
 ---
 title: Releases
-sidebar_position: 3
+sidebar_position: 4
 hide_title: true
 ---
 import TierLabel from "../_components/TierLabel";