Document node selectors for sharding (#176)

This updates sharding documentation to take node selectors, and the new
sharding parameters syntax, into account.

docs/cli/fleet-controller/fleetcontroller_gitjob.md

@@ -22,6 +22,7 @@ fleetcontroller gitjob [flags]
       --listen string                 The port the webhook listens. (default ":8080")
       --metrics-bind-address string   The address the metric endpoint binds to. (default ":8081")
       --namespace string              namespace to watch (default "cattle-fleet-system")
+      --shard-node-selector string    node selector to apply to jobs based on the shard ID, if any
 ```
 
 ### Options inherited from parent commands

docs/installation.md

@@ -86,30 +86,46 @@ You can now [register some git repos](./gitrepo-add.md) in the `fleet-local` nam
 
 ### Deployment
 
-From 0.10 onwards, Fleet supports static sharding. The Fleet controller chart can be installed with `--set
+From 0.10 onwards, Fleet supports static sharding.
-shards={<comma-separated shard IDs>}`, which will result in:
+Each shard is defined by its shard ID.
-* as many Fleet controller deployments as specified unique shard IDs,
+Optionally, a shard can have a [node
+selector](https://kubernetes.io/docs/concepts/scheduling-eviction/assign-pod-node/#nodeselector), instructing Fleet to
+create all controller pods and jobs for that shard on nodes matching that selector.
+
+The Fleet controller chart can be installed with the following arguments:
+* `--set shards[$index].id=$shard_id`
+* `--set shards[$index].nodeSelector.$key=$value`
+
+This will result in:
+* as many Fleet controller and gitjob deployments as specified unique shard IDs,
 * plus the usual unsharded Fleet controller pod. That latter pod will be the only one containing agent management and
 cleanup containers.
 
 For instance:
 ```bash
-$ helm -n cattle-fleet-system install --create-namespace --wait --set shards="{foo,bar,baz}" \
+$ helm -n cattle-fleet-system install --create-namespace --wait fleet fleet/fleet \
-fleet fleet/fleet
+  --set shards[0].id=foo \
-
+  --set shards[0].nodeSelector."kubernetes\.io/hostname"=k3d-upstream-server-0 \
-$ kubectl -n cattle-fleet-system get pods -l app=fleet-controller
+  --set shards[1].id=bar \
-NAME                                          READY   STATUS    RESTARTS      AGE
+  --set shards[1].nodeSelector."kubernetes\.io/hostname"=k3d-upstream-server-1 \
-fleet-controller-78c74fdb85-b6q64             3/3     Running   0             77s
+  --set shards[2].id=baz \
-fleet-controller-shard-bar-777d888865-w2dks   1/1     Running   0             77s
+  --set shards[2].nodeSelector."kubernetes\.io/hostname"=k3d-upstream-server-2 \
-fleet-controller-shard-baz-6595bd9cb9-27whg   1/1     Running   0             77s
-fleet-controller-shard-foo-85d49b446f-pzxkw   1/1     Running   0             77s
 
 $ kubectl -n cattle-fleet-system get pods -l app=fleet-controller \
--o=jsonpath='{range .items[*]}{.metadata.name}{"\t"}{.metadata.labels.fleet\.cattle\.io/shard-id}{"\n"}{end}'
+    -o=custom-columns='Name:.metadata.name,Shard-ID:.metadata.labels.fleet\.cattle\.io/shard-id,Node:spec.nodeName'
-fleet-controller-78c74fdb85-b6q64
+Name                                          Shard-ID   Node
-fleet-controller-shard-bar-777d888865-w2dks     bar
+fleet-controller-b4c469c85-rj2q8                         k3d-upstream-server-2
-fleet-controller-shard-baz-6595bd9cb9-27whg     baz
+fleet-controller-shard-bar-5f5999958f-nt4bm   bar        k3d-upstream-server-1
-fleet-controller-shard-foo-85d49b446f-pzxkw     foo
+fleet-controller-shard-baz-75c8587898-2wkk9   baz        k3d-upstream-server-2
+fleet-controller-shard-foo-55478fb9d8-42q2f   foo        k3d-upstream-server-0
+
+$ kubectl -n cattle-fleet-system get pods -l app=gitjob \
+    -o=custom-columns='Name:.metadata.name,Shard-ID:.metadata.labels.fleet\.cattle\.io/shard-id,Node:spec.nodeName'
+Name                                Shard-ID   Node
+gitjob-8498c6d78b-mdhgh                        k3d-upstream-server-1
+gitjob-shard-bar-8659ffc945-9vtlx   bar        k3d-upstream-server-1
+gitjob-shard-baz-6d67f596dc-fsz9m   baz        k3d-upstream-server-2
+gitjob-shard-foo-8697bb7f67-wzsfj   foo        k3d-upstream-server-0
 ```
 
 ### How it works

versioned_docs/version-0.10/cli/fleet-controller/fleetcontroller_gitjob.md

@@ -30,6 +30,7 @@ fleetcontroller gitjob [flags]
       --disable-gitops    disable gitops components
       --disable-metrics   disable metrics
       --shard-id string   only manage resources labeled with a specific shard ID
+      --shard-node-selector string    node selector to apply to jobs based on the shard ID, if any
 ```
 
 ### SEE ALSO

versioned_docs/version-0.10/installation.md

@@ -86,30 +86,46 @@ You can now [register some git repos](./gitrepo-add.md) in the `fleet-local` nam
 
 ### Deployment
 
-From 0.10 onwards, Fleet supports static sharding. The Fleet controller chart can be installed with `--set
+From 0.10 onwards, Fleet supports static sharding.
-shards={<comma-separated shard IDs>}`, which will result in:
+Each shard is defined by its shard ID.
-* as many Fleet controller deployments as specified unique shard IDs,
+Optionally, a shard can have a [node
+selector](https://kubernetes.io/docs/concepts/scheduling-eviction/assign-pod-node/#nodeselector), instructing Fleet to
+create all controller pods and jobs for that shard on nodes matching that selector.
+
+The Fleet controller chart can be installed with the following arguments:
+* `--set shards[$index].id=$shard_id`
+* `--set shards[$index].nodeSelector.$key=$value`
+
+This will result in:
+* as many Fleet controller and gitjob deployments as specified unique shard IDs,
 * plus the usual unsharded Fleet controller pod. That latter pod will be the only one containing agent management and
 cleanup containers.
 
 For instance:
 ```bash
-$ helm -n cattle-fleet-system install --create-namespace --wait --set shards="{foo,bar,baz}" \
+$ helm -n cattle-fleet-system install --create-namespace --wait fleet fleet/fleet \
-fleet fleet/fleet
+  --set shards[0].id=foo \
-
+  --set shards[0].nodeSelector."kubernetes\.io/hostname"=k3d-upstream-server-0 \
-$ kubectl -n cattle-fleet-system get pods -l app=fleet-controller
+  --set shards[1].id=bar \
-NAME                                          READY   STATUS    RESTARTS      AGE
+  --set shards[1].nodeSelector."kubernetes\.io/hostname"=k3d-upstream-server-1 \
-fleet-controller-78c74fdb85-b6q64             3/3     Running   0             77s
+  --set shards[2].id=baz \
-fleet-controller-shard-bar-777d888865-w2dks   1/1     Running   0             77s
+  --set shards[2].nodeSelector."kubernetes\.io/hostname"=k3d-upstream-server-2 \
-fleet-controller-shard-baz-6595bd9cb9-27whg   1/1     Running   0             77s
-fleet-controller-shard-foo-85d49b446f-pzxkw   1/1     Running   0             77s
 
 $ kubectl -n cattle-fleet-system get pods -l app=fleet-controller \
--o=jsonpath='{range .items[*]}{.metadata.name}{"\t"}{.metadata.labels.fleet\.cattle\.io/shard-id}{"\n"}{end}'
+    -o=custom-columns='Name:.metadata.name,Shard-ID:.metadata.labels.fleet\.cattle\.io/shard-id,Node:spec.nodeName'
-fleet-controller-78c74fdb85-b6q64
+Name                                          Shard-ID   Node
-fleet-controller-shard-bar-777d888865-w2dks     bar
+fleet-controller-b4c469c85-rj2q8                         k3d-upstream-server-2
-fleet-controller-shard-baz-6595bd9cb9-27whg     baz
+fleet-controller-shard-bar-5f5999958f-nt4bm   bar        k3d-upstream-server-1
-fleet-controller-shard-foo-85d49b446f-pzxkw     foo
+fleet-controller-shard-baz-75c8587898-2wkk9   baz        k3d-upstream-server-2
+fleet-controller-shard-foo-55478fb9d8-42q2f   foo        k3d-upstream-server-0
+
+$ kubectl -n cattle-fleet-system get pods -l app=gitjob \
+    -o=custom-columns='Name:.metadata.name,Shard-ID:.metadata.labels.fleet\.cattle\.io/shard-id,Node:spec.nodeName'
+Name                                Shard-ID   Node
+gitjob-8498c6d78b-mdhgh                        k3d-upstream-server-1
+gitjob-shard-bar-8659ffc945-9vtlx   bar        k3d-upstream-server-1
+gitjob-shard-baz-6d67f596dc-fsz9m   baz        k3d-upstream-server-2
+gitjob-shard-foo-8697bb7f67-wzsfj   foo        k3d-upstream-server-0
 ```
 
 ### How it works