Merge pull request #2963 from weaveworks/jp-explorer-docs

Add explorer docs

docs/extending-explorer.md

@@ -0,0 +1,36 @@
+# Extending Explorer
+
+Here is a quick and dirty guide for adding new objects to Explorer.
+
+Things to know:
+
+- All objects are stored in a central store in a single table
+- All objects are normalized to a standard format
+- To differentiate which objects should show up for a given request, we use the `category` field
+- Adding a new object kind creates a new `watch` that will listen for updates on all clusters
+- Here is [an architecture doc](https://github.com/weaveworks/weave-gitops-enterprise/blob/main/docs/architecture/explore.md) that goes into detail
+
+## Adding a new Object Kind
+
+1. Add a new entry in the [`SupportedObjectKinds`](https://github.com/weaveworks/weave-gitops-enterprise/blob/253256c16c777b0d488ca0ba8068b8f80b1b4c07/pkg/query/configuration/objectkind.go#L119) slice
+2. Add an entry to the [`flux` adapters `switch`](https://github.com/weaveworks/weave-gitops-enterprise/blob/253256c16c777b0d488ca0ba8068b8f80b1b4c07/pkg/query/internal/adapters/fluxobject.go#L27)
+3. Add an [RBAC entry](https://github.com/weaveworks/weave-gitops-enterprise/blob/9101b60a487e1f999b4e988e9ca27bdde4ac7538/charts/mccp/templates/clusters-service/collector.yaml#L13) to WeGO ServiceAccount for your kind
+
+## Using the Explorer UI component
+
+If you would like to view your object list in a dedicated table:
+
+1. Add a new [`ObjectCategory`](https://github.com/weaveworks/weave-gitops-enterprise/blob/253256c16c777b0d488ca0ba8068b8f80b1b4c07/pkg/query/internal/models/object.go#L13) variable
+2. Add a category entry to the [`adapters`](https://github.com/weaveworks/weave-gitops-enterprise/blob/253256c16c777b0d488ca0ba8068b8f80b1b4c07/pkg/query/internal/adapters/fluxobject.go#L72)
+
+3. Instantiate the `<Explorer />` UI component with the `category` prop, like so:
+
+```jsx
+function MyComponent() {
+  return (
+    <div>
+      <Explorer category="gitopssets" />
+    </div>
+  );
+}
+```