drnic / ruby-meetup-2018-11-27

Knative examples for Ruby Meetup

Build demo images

docker build -t drnic/meetup:v1 meetup-v1
docker build -t drnic/meetup:v2 meetup-v2

docker push drnic/meetup:v1
docker push drnic/meetup:v2

Serving

Deploying v1

$ knctl deploy --service meetup --image drnic/meetup:v1

$ knctl curl -s meetup
Hello v1!

Local DNS routing to remote cluster

knctl curl is necessary because the generated routes aren't real. We can use kwt to map all Knative routes from local machine to remote Kubernetes cluster:

sudo -E kwt net start --dns-map-exec='knctl dns-map'

In another terminal:

curl meetup.default.example.com

Or can access website in local browser now.

Deploying v2

Knative does not require explicitly tagged images, but we can use them:

$ knctl deploy --service meetup --image drnic/meetup:v2

$ knctl curl -s meetup
Hello v2!

The difference between :v1 and :v2 is an environment variable TARGET. We can override this on our next deploy:

$ knctl deploy --service meetup --image drnic/meetup:v2 --env TARGET="revision 3"
$ knctl curl -s meetup
Hello revision 3!

Revisions are explicit

$ knctl revisions list
Service  Name          Tags      Annotations  Conditions  Age  Traffic
meetup   meetup-00003  latest    -            4 OK / 4    48s  100% -> meetup.default.example.com
~        meetup-00002  previous  -            4 OK / 4    1m   -
~        meetup-00001  -         -            4 OK / 4    10m  -

Rollout of traffic to new revisions

$ knctl deploy --service meetup --image drnic/meetup:v2 \
    --env TARGET="revision 4" \
    --managed-route=false
$ knctl rollout --route meetup -p meetup:previous=80% -p meetup:latest=20%

$ knctl revisions list
Service  Name          Tags      Annotations  Conditions  Age  Traffic
meetup   meetup-00004  latest    -            4 OK / 4    1m   20% -> meetup.default.example.com
~        meetup-00003  previous  -            4 OK / 4    3m   80% -> meetup.default.example.com
~        meetup-00002  -         -            2 OK / 4    3m   -
~        meetup-00001  -         -            2 OK / 4    12m  -

Later:

$ knctl rollout --route meetup -p meetup:previous=50% -p meetup:latest=50%
$ knctl revisions list
Service  Name          Tags      Annotations  Conditions  Age  Traffic
meetup   meetup-00004  latest    -            4 OK / 4    4m   50% -> meetup.default.example.com
~        meetup-00003  previous  -            4 OK / 4    6m   50% -> meetup.default.example.com
...

Finally:

$ knctl rollout --route meetup -p meetup:latest=100%
$ knctl revisions list
Revisions

Service  Name          Tags      Annotations  Conditions  Age  Traffic
meetup   meetup-00004  latest    -            4 OK / 4    5m   100% -> meetup.default.example.com
~        meetup-00003  previous  -            4 OK / 4    6m   -
...