How to update secret with "kubectl patch --type='json'" - kubernetes

Question

I created a secret like this:
kubectl create secret generic test --from-literal=username=testuser --from-literal=password=12345
I want to update the username to testuser2 but I want to do it only with kubectl patch --type='json'.
This is how I tried to do it:
kubectl patch secret test --type='json' -p='[{"data":{"username": "testuser 2"}}]' -v=1
But I received:
The "" is invalid
Remember, I want to do it with the option of --type='json', no other workarounds.

Answer 1

I found how to do it after I read here that referred me to this great article.
This is the JSON secret:
{
"apiVersion": "v1",
"data": {
"password": "aWx1dnRlc3Rz",
"username": "dGVzdHVzZXI="
},
"kind": "Secret",
"metadata": {
"creationTimestamp": "2019-04-18T11:37:09Z",
"name": "test",
"namespace": "default",
"resourceVersion": "3017",
"selfLink": "/api/v1/namespaces/default/secrets/test",
"uid": "4d0a763e-61ce-11e9-92b6-0242ac110015"
},
"type": "Opaque"
}
Therefore, to update the user's field I needed to create the JSON Patch format:
[
{
"op" : "replace" ,
"path" : "/data/username" ,
"value" : "dGVzdHVzZXIy" # testuser2 in base64
}
]
Notice that the value should be in base64.
The result is:
kubectl patch secret test --type='json' -p='[{"op" : "replace" ,"path" : "/data/username" ,"value" : "dGVzdHVzZXIy"}]'

Answer 2

This is what I do in order to replace the secret:
kubectl patch secret my-secret --patch="{\"data\": { \"NEW_PASSWORD\": \"$(echo -n mypassword |base64 -w0)\" }}" -oyaml

Answer 3

This command solved my issue on version 1.24.x:
kubectl patch secret app-sec --patch="{\"data\": { \"license-id\": \"TEST\" }}" -oyaml