Istio: Path based basic auth

[dweidenfeld]

Describe the feature request
I would expect that istio supports basic authentication for routing.

E.g. like this:

apiVersion: "authentication.istio.io/v1alpha1"
kind: "Policy"
metadata:
  name: "jwt-example"
spec:
  targets:
  - name: httpbin
  origins:
  - basic:
      secret: "k8s-basic-auth-secret"
      trigger_rules:
      - included_paths:
        - exact: /documentation
  principalBinding: USE_ORIGIN

or

apiVersion: "authentication.istio.io/v1alpha1"
kind: "Policy"
metadata:
  name: "jwt-example"
spec:
  targets:
  - name: httpbin
  origins:
  - basic:
      users: 
      - "myuser:mypassword"
      trigger_rules:
      - included_paths:
        - exact: /documentation
  principalBinding: USE_ORIGIN

Describe alternatives you've considered
I thought about adding another NGINX proxy in front of the the service, but I do not really want to decrease the performance of each HTTP request by adding another layer.

Affected product area (please put an X in all that apply)

[ ] Configuration Infrastructure
[ ] Docs
[ ] Installation
[ ] Networking
[ ] Performance and Scalability
[ ] Policies and Telemetry
[x] Security
[ ] Test and Release
[ ] User Experience
[ ] Developer Infrastructure

Additional context

[yangminzhu]

We're working to improve the current authentication API, the next version should be more flexible to support such use cases. For example, the basic authentication could be one of the authenticators.

cc @diemtvu

[istio-policy-bot]

🚧 This issue or pull request has been closed due to not having had activity from an Istio team member since 2019-07-02. If you feel this issue or pull request deserves attention, please reopen the issue. Please see this wiki page for more information. Thank you for your contributions.

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