knative/client v0.19.0

Knative Client release v0.19.0

on GitHub

kn 0.19.0 introduces two new commands (kn service apply and kn service import) and removes some deprecated options, in addition to bug fixes and some other goodies described below.

Meta

The compile dependencies have been updated to Knative Serving 0.19.0 and Knative Eventing 0.19.0. There are no changes in the used API version for communicating with the backend.

Removed deprecated options

The following deprecated options have been removed:

• --async for all CRUD commands. Use --no-wait instead
• --requests-cpu, --request-memory, --limits-cpu and --limits-memory when managing services. The replacement is to use --limit memory=.. and --limit cpu=... (same for --request). Both options can be combined as in --limit memory=256Mi,cpu=500m

kn service apply

A new kn service apply command has been added to allow a declarative management for your Knative service.
This new command is especially useful in can CI/CD context to allow for idempotent operations when creating or updating services.
It works much like kubectl apply and used a client-side 3-way merge algorithm to update service. The kubectl merge algorithm is directly reused here.
As apply operates on Knative's custom resource types, it suffers the same limitation as the client-side merge algorithm in kubectl apply when dealing with CRDs.
I.e. arrays can't be merged but are just overwritten by an update.
This limitation affects all containers specific parameters.

For the future, we plan to add a better merge algorithm that supports a full strategic 3-way merge like the support of kubectl apply has for intrinsic K8s resources.

It is important to note that kn service apply is fundamentally different to kn service update as with kn service apply the full configuration needs to be provided as command-line options or within a declaration file when used with --filename.
With kn service update you only specify the parts to be updated and don't touch any other service configuration.
This characteristic of apply also implies that you always have to provide the image as the only mandatory parameter with kn service apply.

For example:

# Initially apply a service with the given image and env var
kn service apply random --image rhuss/random:1.0 --env foo=bar

# Update the service to add a ying=yang env var to the already existing one
kn service update random --env ying=yang

# Apply a full new configuration. Note that foo=bar will be removed
# because it is not specified here.
kn service apply random --image rhuss/random:1.0 --env ying=yang

kn service import

kn service import is the counterpart to kn service export and allows you to import a Service and all active revision that has been exported.
Active revisions are revisions that are referenced in a traffic-split.

This command is still marked experimental, and there are some known issues in the import how the generation of revision are created.
Please gives us feedback on how we can improve the support for this feature.

Other

The following other features have been added, too:

• An arm64 flavour has been added to the released artefacts, as well as a checksum.txt which caries the sha256sum of all artefacts.
• A channel: prefix has been added for --sink parameters, so that channels can be directly addressed by name.
• Aliases are now appearing correctly in the help messages
• The Client API as a new list filter WithLabel() which can be used when listing services.

You can find the full list of changes in the CHANGELOG.