* Abort Kubernetes Ingress update if Kubernetes API call fails
Currently if a Kubernetes API call fails we potentially remove a working service from Traefik. This changes it so if a Kubernetes API call fails we abort out of the ingress update and use the current working config. Github issue: #1240
Also added a test to cover when requested resources (services and endpoints) that the user has specified don’t exist.
* Specifically capturing the tc range as documented here: https://blog.golang.org/subtests
* Updating service names in the mock data to be more clear
* Updated expected data to match what currently happens in the loadIngress
* Adding a blank Servers to the expected output so we compare against that instead of nil.
* Replacing the JSON test output with spew for the TestMissingResources test to help ensure we have useful output incase of failures
* Adding a temporary fix to the GetEndoints mocked function so we can override the return value for if the endpoints exist.
After the 1.2 release the use of properExists should be removed and the GetEndpoints function should return false for the second value indicating the endpoint doesn’t exist. However at this time that would break a lot of the tests.
* Adding quick TODO line about removing the properExists property
* Link to issue 1307 re: properExists flag.
Only use one channel for all watches
Re-use stop channel from the provider
Skip events that have already been handled by the provider, builds on 007f8cc48ea9504bb7754c5e3244124be422f47d
Since we already know the name and namespace
of the service(s) we want we can just get the
correct one back from the API without filtering
the results.
* Potentialy saves a network hop
* Ability to configure LB algothim (given some work to expose an
anotation etc...)
* K8s config Watch is triggered far less often
By design k8s ingress is only designed to ballance services from within
the namespace of the ingress.
This is disscuessed a little in
https://github.com/kubernetes/kubernetes/issues/17088.
For now traefik should only reference the services in the current
namespace. For me this was a confusing change of behaviour
from the reference implimentations, as I have services
with the same name in each namespace.
If the flag kubernetes.namespaces is set...
Then we only select ingresses from that/those namespace(s)
This allows multiple instances of traefik to
independently load balance for each namespace.
This could be for logical or security reasons.
Addresses #336
