Fix crashes with Service of type ExternalName

lib/kubernetes-deploy/kubernetes_resource/service.rb

@@ -11,7 +11,9 @@ def sync
     end
 
     def status
-      if @num_pods_selected.blank?
+      if !requires_endpoints?
+        "Doesn't require any endpoint"
+      elsif @num_pods_selected.blank?
         "Failed to count related pods"
       elsif selects_some_pods?
         "Selects at least 1 pod"
@@ -21,6 +23,7 @@ def status
     end
 
     def deploy_succeeded?
+      return exists? unless requires_endpoints?
       # We can't use endpoints if we want the service to be able to fail fast when the pods are down
       exposes_zero_replica_deployment? || selects_some_pods?
     end
@@ -44,28 +47,40 @@ def exposes_zero_replica_deployment?
       @related_deployment_replicas == 0
     end
 
+    def requires_endpoints?
+      return false if external_name_svc?
+      return true if @related_deployment_replicas.blank?
+      @related_deployment_replicas > 0
+    end
+
     def selects_some_pods?
       return false unless @num_pods_selected
       @num_pods_selected > 0
     end
 
     def selector
-      @selector ||= @definition["spec"]["selector"].map { |k, v| "#{k}=#{v}" }.join(",")
+      @selector ||= @definition["spec"].fetch("selector", []).map { |k, v| "#{k}=#{v}" }.join(",")
     end
 
     def fetch_related_pod_count
+      return 0 unless selector.present?
       raw_json, _err, st = kubectl.run("get", "pods", "--selector=#{selector}", "--output=json")
       return unless st.success?
       JSON.parse(raw_json)["items"].length
     end
 
     def fetch_related_replica_count
+      return 0 unless selector.present?
       raw_json, _err, st = kubectl.run("get", "deployments", "--selector=#{selector}", "--output=json")
       return unless st.success?
 
       deployments = JSON.parse(raw_json)["items"]
       return unless deployments.length == 1
       deployments.first["spec"]["replicas"].to_i
     end
+
+    def external_name_svc?
+      @definition["spec"]["type"] == "ExternalName"
+    end
   end
 end

test/fixtures/hello-cloud/redis.yml

@@ -12,6 +12,17 @@ spec:
   selector:
     name: redis
 ---
+apiVersion: v1
+kind: Service
+metadata:
+  name: redis-external
+  labels:
+    name: redis-external
+    app: hello-cloud
+spec:
+  externalName: external-redis.shopify
+  type: ExternalName
+---
 kind: PersistentVolumeClaim
 apiVersion: v1
 metadata:

test/integration/kubernetes_deploy_test.rb

@@ -11,7 +11,7 @@ def test_full_hello_cloud_set_deploy_succeeds
       "Deploying ConfigMap/hello-cloud-configmap-data (timeout: 30s)",
       "Hello from the command runner!", # unmanaged pod logs
       "Result: SUCCESS",
-      "Successfully deployed 14 resources"
+      "Successfully deployed 15 resources"
     ], in_order: true)
 
     assert_logs_match_all([
@@ -59,7 +59,7 @@ def test_pruning_works
       'daemonset "ds-app"',
       'statefulset "stateful-busybox"'
     ] # not necessarily listed in this order
-    expected_msgs = [/Pruned 7 resources and successfully deployed 3 resources/]
+    expected_msgs = [/Pruned 7 resources and successfully deployed 4 resources/]
     expected_pruned.map do |resource|
       expected_msgs << /The following resources were pruned:.*#{resource}/
     end
@@ -627,7 +627,7 @@ def test_can_deploy_deployment_with_zero_replicas
     assert_equal 0, pods.length, "Pods were running from zero-replica deployment"
 
     assert_logs_match_all([
-      %r{Service/web\s+Selects 0 pods},
+      %r{Service/web\s+Doesn't require any endpoint},
       %r{Deployment/web\s+0 replicas}
     ])
   end