Merge branch '22864-kubernetes-deploy-with-terminal' into 'master'

Add online terminal support for Kubernetes

## What does this MR do?

Gives terminal access to kubernetes-deployed environments  via the deployment service

## Are there points in the code the reviewer needs to double check?

## Why was this MR needed?

Part of idea to production

## Screenshots (if relevant)

### `/root/reviewing/environments`

![Screen_Shot_2016-12-15_at_19.10.40](/uploads/bd2c54c07b6c85dec3328a20cd185b64/Screen_Shot_2016-12-15_at_19.10.40.png)

### `/root/reviewing/environments/10013`

![Screen_Shot_2016-12-19_at_12.52.39](/uploads/db4e4e06cda88437e8727433d65898b9/Screen_Shot_2016-12-19_at_12.52.39.png)

### `/root/reviewing/enviroments/10013/terminal`

![Screen_Shot_2016-12-15_at_02.35.52](/uploads/1bb77b7e2de2c657ae3bda62dc4f0970/Screen_Shot_2016-12-15_at_02.35.52.png)

## Does this MR meet the acceptance criteria?

- [x] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) added
- [x] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- Tests
  - [X] Added for this feature/bug
  - [x] All builds are passing
- [X] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [X] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if it does - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?

* Closes #22864 #22958
* Alternative to, and somewhat based on,  !6770 
* Depends on https://gitlab.com/gitlab-org/gitlab-workhorse/merge_requests/83

See merge request !7690

1 files changed, 84 insertions, 25 deletions

diff --git a/spec/models/project_services/kubernetes_service_spec.rb b/spec/models/project_services/kubernetes_service_spec.rb
index 3603602e41d..4f3cd14e941 100644
--- a/spec/models/project_services/kubernetes_service_spec.rb
+++ b/spec/models/project_services/kubernetes_service_spec.rb
@@ -1,7 +1,29 @@
 require 'spec_helper'
 
-describe KubernetesService, models: true do
-  let(:project) { create(:empty_project) }
+describe KubernetesService, models: true, caching: true do
+  include KubernetesHelpers
+  include ReactiveCachingHelpers
+
+  let(:project) { create(:kubernetes_project) }
+  let(:service) { project.kubernetes_service }
+
+  # We use Kubeclient to interactive with the Kubernetes API. It will
+  # GET /api/v1 for a list of resources the API supports. This must be stubbed
+  # in addition to any other HTTP requests we expect it to perform.
+  let(:discovery_url) { service.api_url + '/api/v1' }
+  let(:discovery_response) { { body: kube_discovery_body.to_json } }
+
+  let(:pods_url) { service.api_url + "/api/v1/namespaces/#{service.namespace}/pods" }
+  let(:pods_response) { { body: kube_pods_body(kube_pod).to_json } }
+
+  def stub_kubeclient_discover
+    WebMock.stub_request(:get, discovery_url).to_return(discovery_response)
+  end
+
+  def stub_kubeclient_pods
+    stub_kubeclient_discover
+    WebMock.stub_request(:get, pods_url).to_return(pods_response)
+  end
 
   describe "Associations" do
     it { is_expected.to belong_to :project }
@@ -65,22 +87,15 @@ describe KubernetesService, models: true do
   end
 
   describe '#test' do
-    let(:project) { create(:kubernetes_project) }
-    let(:service) { project.kubernetes_service }
-    let(:discovery_url) { service.api_url + '/api/v1' }
-
-    # JSON response body from Kubernetes GET /api/v1 request
-    let(:discovery_response) { { "kind" => "APIResourceList", "groupVersion" => "v1", "resources" => [] }.to_json }
+    before do
+      stub_kubeclient_discover
+    end
 
     context 'with path prefix in api_url' do
       let(:discovery_url) { 'https://kubernetes.example.com/prefix/api/v1' }
 
-      before do
-        service.api_url = 'https://kubernetes.example.com/prefix/'
-      end
-
       it 'tests with the prefix' do
-        WebMock.stub_request(:get, discovery_url).to_return(body: discovery_response)
+        service.api_url = 'https://kubernetes.example.com/prefix/'
 
         expect(service.test[:success]).to be_truthy
         expect(WebMock).to have_requested(:get, discovery_url).once
@@ -88,17 +103,12 @@ describe KubernetesService, models: true do
     end
 
     context 'with custom CA certificate' do
-      let(:certificate) { "CA PEM DATA" }
-      before do
-        service.update_attributes!(ca_pem: certificate)
-      end
-
       it 'is added to the certificate store' do
-        cert = double("certificate")
+        service.ca_pem = "CA PEM DATA"
 
-        expect(OpenSSL::X509::Certificate).to receive(:new).with(certificate).and_return(cert)
+        cert = double("certificate")
+        expect(OpenSSL::X509::Certificate).to receive(:new).with(service.ca_pem).and_return(cert)
         expect_any_instance_of(OpenSSL::X509::Store).to receive(:add_cert).with(cert)
-        WebMock.stub_request(:get, discovery_url).to_return(body: discovery_response)
 
         expect(service.test[:success]).to be_truthy
         expect(WebMock).to have_requested(:get, discovery_url).once
@@ -107,17 +117,15 @@ describe KubernetesService, models: true do
 
     context 'success' do
       it 'reads the discovery endpoint' do
-        WebMock.stub_request(:get, discovery_url).to_return(body: discovery_response)
-
         expect(service.test[:success]).to be_truthy
         expect(WebMock).to have_requested(:get, discovery_url).once
       end
     end
 
     context 'failure' do
-      it 'fails to read the discovery endpoint' do
-        WebMock.stub_request(:get, discovery_url).to_return(status: 404)
+      let(:discovery_response) { { status: 404 } }
 
+      it 'fails to read the discovery endpoint' do
         expect(service.test[:success]).to be_falsy
         expect(WebMock).to have_requested(:get, discovery_url).once
       end
@@ -156,4 +164,55 @@ describe KubernetesService, models: true do
       )
     end
   end
+
+  describe '#terminals' do
+    let(:environment) { build(:environment, project: project, name: "env", slug: "env-000000") }
+    subject { service.terminals(environment) }
+
+    context 'with invalid pods' do
+      it 'returns no terminals' do
+        stub_reactive_cache(service, pods: [ { "bad" => "pod" } ])
+
+        is_expected.to be_empty
+      end
+    end
+
+    context 'with valid pods' do
+      let(:pod) { kube_pod(app: environment.slug) }
+      let(:terminals) { kube_terminals(service, pod) }
+
+      it 'returns terminals' do
+        stub_reactive_cache(service, pods: [ pod, pod, kube_pod(app: "should-be-filtered-out") ])
+
+        is_expected.to eq(terminals + terminals)
+      end
+    end
+  end
+
+  describe '#calculate_reactive_cache' do
+    before { stub_kubeclient_pods }
+    subject { service.calculate_reactive_cache }
+
+    context 'when service is inactive' do
+      before { service.active = false }
+
+      it { is_expected.to be_nil }
+    end
+
+    context 'when kubernetes responds with valid pods' do
+      it { is_expected.to eq(pods: [kube_pod]) }
+    end
+
+    context 'when kubernetes responds with 500' do
+      let(:pods_response) { { status: 500 } }
+
+      it { expect { subject }.to raise_error(KubeException) }
+    end
+
+    context 'when kubernetes responds with 404' do
+      let(:pods_response) { { status: 404 } }
+
+      it { is_expected.to eq(pods: []) }
+    end
+  end
 end