Add --no-extras flag to join command

[rgee0]

Why do you need this?

It was found that when joining servers to a cluster any additional servers would not honour the --no-extras flag used with the install command.

It is necessary, therefore, for the flag to be added to join and only be applied in situations where --server has been provided.

• I have raised an issue to propose this change (required)

Although closed, #408 refers

Description

Adds --no-extras to the join command such that it will work when used with --server.

How Has This Been Tested?

Add new flag without --server

$ ./k3sup-darwin join \             
  --ip $SERVER_IP_2 \
  --user $USER \
  --server-user $USER \
  --server-ip $SERVER_IP \
  --no-extras --print-command

Error: --no-extras can only be used with --server

Add new flag with --server

 $ ./k3sup-darwin join \
  --ip $SERVER_IP_2 \
  --user $USER \
  --server-user $USER \
  --server-ip $SERVER_IP \
  --no-extras --print-command --server

Running: k3sup join
Joining 209.97.141.169 => 138.68.158.53
ssh: sudo cat /var/lib/rancher/k3s/server/node-token

Received node-token from 138.68.158.53.. ok.
ssh: curl -sfL https://get.k3s.io | K3S_URL='https://138.68.158.53:6443'  \
K3S_TOKEN='<token>::server:<alphanumeric>' \
INSTALL_K3S_CHANNEL='stable' \
INSTALL_K3S_EXEC='server --server https://138.68.158.53:6443' \
sh -s -  --disable servicelb --disable traefik

Note the addition of --disable servicelb --disable traefik to the output command

With --tls-san added as this was in the area of change:

$ ./k3sup-darwin join \
  --ip $SERVER_IP_2 \
  --user $USER \
  --server-user $USER \
  --server-ip $SERVER_IP \
  --no-extras --print-command --server  --tls-san 127.0.0.1
Running: k3sup join
Joining 209.97.141.169 => 138.68.158.53
ssh: sudo cat /var/lib/rancher/k3s/server/node-token

Received node-token from 138.68.158.53.. ok.
ssh: curl -sfL https://get.k3s.io | K3S_URL='https://138.68.158.53:6443' K3S_TOKEN='<alphanumeric>::server:<alphanumeric>' INSTALL_K3S_CHANNEL='stable' INSTALL_K3S_EXEC='server --server https://138.68.158.53:6443 --tls-san 127.0.0.1' sh -s -  --disable servicelb --disable traefik

With --tls-san and without --server:

./k3sup-darwin join \
  --ip $SERVER_IP_2 \
  --user $USER \
  --server-user $USER \
  --server-ip $SERVER_IP \
  --print-command  --tls-san 127.0.0.1 
Error: --tls-san can only be used with --server

Demonstrates previous behaviour unchanged

Additional Test case using --no-extras with --k3s-extra-args set:

• Install the initial server with --cluster:

➜  bin git:(NoExtrasOnJoin) ./k3sup-darwin install --ip $SERVER_IP --user root --no-extras --cluster
Running: k3sup install
2023/12/30 12:12:18 165.232.97.194
Public IP: 165.232.97.194
[INFO]  ...
[INFO]  systemd: Starting k3s

• Join the second server with --no-extras & --k3s-extra-args:

➜  bin git:(NoExtrasOnJoin) ./k3sup-darwin join \                                                
  --ip $SERVER_IP_2 \
  --user $USER \
  --server-user $USER \
  --server-ip $SERVER_IP \
  --print-command  \
  --server \
  --no-extras \
  --k3s-extra-args "--node-taint key=value:NoExecute"

Running: k3sup join
Joining 165.232.97.185 => 165.232.97.194
ssh: sudo cat /var/lib/rancher/k3s/server/node-token

Received node-token from 165.232.97.194.. ok.
ssh: curl -sfL https://get.k3s.io | \
K3S_URL='https://165.232.97.194:6443' \
K3S_TOKEN='<alphanumeric>::server:<alphanumeric>' \
INSTALL_K3S_CHANNEL='stable' \
INSTALL_K3S_EXEC='server --server https://165.232.97.194:6443' \
sh -s - --node-taint key=value:NoExecute --disable servicelb --disable traefik
[INFO]  ...
[INFO]  systemd: Starting k3s

Verify that the extra args have been appropriately concatenated within the print-command output.

• Inspect the nodes and pods to check that the disable flags have been handled correctly:

➜  bin git:(NoExtrasOnJoin) export KUBECONFIG=<path>
➜  bin git:(NoExtrasOnJoin) kubectl config use-context default
Switched to context "default".
➜  bin git:(NoExtrasOnJoin) kubectl get node -o wide
NAME           STATUS   ROLES                       AGE     VERSION        INTERNAL-IP      EXTERNAL-IP   OS-IMAGE             KERNEL-VERSION      CONTAINER-RUNTIME
k3s-up-do-01   Ready    control-plane,etcd,master   2m40s   v1.28.4+k3s2   165.232.97.194   <none>        Ubuntu 22.04.2 LTS   5.15.0-67-generic   containerd://1.7.7-k3s1
k3s-up-do-02   Ready    control-plane,etcd,master   39s     v1.28.4+k3s2   165.232.97.185   <none>        Ubuntu 22.04.2 LTS   5.15.0-67-generic   containerd://1.7.7-k3s1
➜  bin git:(NoExtrasOnJoin) kubectl get pods --all-namespaces                                    
NAMESPACE     NAME                                      READY   STATUS    RESTARTS   AGE
kube-system   coredns-6799fbcd5-ln52n                   1/1     Running   0          2m38s
kube-system   local-path-provisioner-84db5d44d9-wjwp4   1/1     Running   0          2m38s
kube-system   metrics-server-67c658944b-cxvjj           1/1     Running   0          2m38s

• Finally check that the no-taint value provided in --k3-extra-args has also been applied:

➜  bin git:(NoExtrasOnJoin) kubectl get nodes -o json | jq '.items[].spec'

{
  "podCIDR": "10.42.0.0/24",
  "podCIDRs": [
    "10.42.0.0/24"
  ],
  "providerID": "k3s://k3s-up-do-01"
}
{
  "podCIDR": "10.42.1.0/24",
  "podCIDRs": [
    "10.42.1.0/24"
  ],
  "providerID": "k3s://k3s-up-do-02",
  "taints": [
    {
      "effect": "NoExecute",
      "key": "key",
      "value": "value"
    }
  ]
}

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I've read the CONTRIBUTION guide
• I have signed-off my commits with git commit -s
• I have added tests to cover my changes.
• All new and existing tests passed.

[alexellis]

LGTM. Thank you for helping to fix a confusing bug 👍

[alexellis]

Could you check whether --no-extras gets correctly merged with anything passed via --k3s-extra-args?

[rgee0]

Could you check whether --no-extras gets correctly merged with anything passed via --k3s-extra-args?

Updated the test output above with Additional Test case using --no-extras with --k3s-extra-args set:

TL;DR is that it merges the values from the --no-extras flag correctly

[alexellis]

Thanks @rgee0