Upgrade to Knative v0.4

[kameshsampath]

Upgrade the Knative installation to use v0.4

[kameshsampath]

As the upgrade v.0.4.0 has lot of breaking changes, it better to have all functionalities throughly checked

[kameshsampath]

@burrsutter - please add anything that you want to check specifically

[bbrowning]

cc @lberk - based on some Slack discussions it sounds like you may be looking at both this tutorial and 0.4 in the near future :)

[kameshsampath]

@lberk - thanks

[lberk]

@bbrowning @kameshsampath Please see PR77 for some fixes to help get the tutorial working on 0.4.0

[rhuss]

One issue I have with 0.4.0 is that the revision names are not predictable. I.e. its not greeter-0001 as used in the tutorial but a random suffix, which you can't easily predict in advance and added to the service's revisions array.

I think this part of the tutorial talking about 'pinned revisions' needs serious rework for 0.4.0 as there is no static revision which you can pre-add in deployment descriptor.

[lberk]

@rhuss strategies for this was discussed earlier today, one option is changing the tutorial so that we properly use the randomly generated revision names. @syedriko also mentioned using generation number (annotations I think?) might be a solution

[bbrowning]

You can get the latest created revision for any Knative Service with a kubectl command like:

kubectl get ksvc my-knative-service -o jsonpath="{.status.latestCreatedRevisionName}"

The tutorial will need to be changed to lookup this latest revision name and do a substitution in the yaml stored in the tutorial repo before applying it.

[rhuss]

@kamesh you could introduce a shell function like

function latest_revision() {
   local name=${1}
   local revision=$(kubectl get ksvc $name -o jsonpath="{.status.latestCreatedRevisionName}")
   echo "${name}-${revision}"
}

and then use it like in

kubectl get $(latest_revision my-knative-service)

You get the idea.

[kameshsampath]

@rhuss we fixed this by querying revisions directly with labels and sort by creation stamp ( thanks to @markusthoemmes @bbrowning ) . I have added them to the tutorial. you should see them in next release.