Add rewrites annotation

[jmastr]

Closes #63

[jmastr]

@pleshakov please review

[pleshakov]

@jmastr
Thx for another pull request!

A few suggestions:

• Remove {{if $location.Rewrite}}/{{end}} from location {{$location.Path}}{{if $location.Rewrite}}/{{end}} in the ingress.tmpl. I think it's better to stay transperent. I'll add notes about the necessity to put / at the end of Ingress paths it to the README file.
• Don't validate the service name and the URL in the annotation.

r, _ := regexp.Compile("serviceName=([a-z\\-]+) +rewrite=([/a-z0-9]+)")

A service name can also contain numbers. A URL can contain characters like _. I suggest to not perform validation at all. If a service name is not valid, the controller will simply igoner the service later. If a URL is not correct, NGINX will report error in the logs when the controller does the configuration check before reloading the configuration.

Please look at https://github.com/nginxinc/kubernetes-ingress/blob/master/nginx-plus-controller/nginx/configurator.go#L232 , where we're parsing a similar annotation.

• Add logging. Please add error reporting when the annotation doesn't include all the required parts, similar to https://github.com/nginxinc/kubernetes-ingress/blob/master/nginx-plus-controller/nginx/configurator.go#L232
• It might be helpful to write a unit test similar to this one https://github.com/nginxinc/kubernetes-ingress/blob/master/nginx-plus-controller/nginx/configurator_test.go

[jmastr]

Very nice! Will do!

[jmastr]

Hi @pleshakov,

I worked in your comments about parsing, logging and testing.

Note that I removed the / at the end of location {{$location.Path}} from my patch, but I added it to examples/rewrites/README.md already to be consistent.

[pleshakov]

@jmastr
Awesome!

Could you replace nginx.com with nginx.org in the following line in configurator.go : glog.Errorf("In %v nginx.com/rewrites contains invalid declaration: %v, ignoring", ingEx.Ingress.Name, err) ?

[jmastr]

@pleshakov done

[pleshakov]

Great. Thx

[pleshakov]

We'll prepare a new release -- https://github.com/nginxinc/kubernetes-ingress/releases -- that will have this and other features. A new tag will be published to the https://hub.docker.com/r/nginxdemos/nginx-ingress/ repo.

[jmastr]

That's awesome! Thank you very, very much!

[jmastr]

I am going to give a talk about this at the next Kubernetes meetup in Berlin, Germany.

[pleshakov]

That's awesome!!