Runtime resource discovery

Gemfile

@@ -11,4 +11,4 @@ gem 'timecop'
 gem 'byebug'
 gem 'codecov', require: false
 gem 'ruby-prof', require: false
-gem 'ruby-prof-flamegraph', require: false
+gem 'ruby-prof-flamegraph', require: false

kubernetes-deploy.gemspec

@@ -24,11 +24,12 @@ Gem::Specification.new do |spec|
 
   spec.required_ruby_version = '>= 2.3.0'
   spec.add_dependency "activesupport", ">= 4.2"
-  spec.add_dependency "kubeclient", "~> 2.4"
+  spec.add_dependency "kubeclient", "~> 2.5.1"
   spec.add_dependency "googleauth", ">= 0.5"
   spec.add_dependency "ejson", "1.0.1"
   spec.add_dependency "colorize", "~> 0.8"
   spec.add_dependency "statsd-instrument", "~> 2.1"
+  spec.add_dependency "jsonpath", "0.8.8"
 
   spec.add_development_dependency "bundler"
   spec.add_development_dependency "rake", "~> 10.0"

lib/kubernetes-deploy/discoverable_resource.rb

@@ -0,0 +1,173 @@
+# frozen_string_literal: true
+require 'kubernetes-deploy/kubernetes_resource'
+require 'kubernetes-deploy/kubeclient_builder'
+require "pry"
+require 'jsonpath'
+
+module KubernetesDeploy
+  class DiscoverableResource < KubernetesResource
+    extend KubernetesDeploy::KubeclientBuilder
+
+    class << self
+      attr_accessor :version, :group, :type
+    end
+
+    STATUS_FIELD_ANNOTATION = 'kubernetes-deploy.shopify.io/status-field'
+    STATUS_SUCCESS_ANNOTATION = 'kubernetes-deploy.shopify.io/status-success'
+    TIMEOUT_ANNOTATION = 'kubernetes-deploy.shopify.io/timeout'
+    PREDEPLOY_ANNOTATION = 'kubernetes-deploy.shopify.io/predeploy'
+    PRUNABLE_ANNOTATION = 'kubernetes-deploy.shopify.io/prunable'
+
+    def type
+      self.class.type
+    end
+
+    def self.inherited(child_class)
+      child_classes.add child_class
+    end
+
+    def self.child_classes
+      @child_classes ||= Set.new
+    end
+
+    def self.prunable?
+      return @prunable if defined?(@prunable)
+      false
+    end
+
+    def self.predeploy?
+      return @predeploy if defined?(@predeploy)
+      false
+    end
+
+    def self.timeout
+      return @timeout if defined?(@timeout)
+      super
+    end
+
+    def self.identity
+      "#{group}/#{version}/#{type}"
+    end
+
+    def self.all
+      child_classes.dup
+    end
+
+    def self.discover(context:, logger:)
+      logger.info("Discovering custom resources:")
+      @resources = nil
+      @child_classes = nil
+      discover_tpr(v1beta1_kubeclient(context))
+      discover_crd(v1beta1_crd_kubeclient(context))
+    end
+
+    def self.build(namespace:, context:, definition:, logger:)
+      # We only discover once per kubernetes-deploy invocation
+      discover(context: context, logger: logger) unless @resources
+
+      type = definition["kind"]
+      group, _, version = definition['apiVersion'].rpartition('/')
+
+      resource_class = @resources.dig(group, type, version) if @resources
+      return super unless resource_class
+
+      opts = { namespace: namespace, context: context, definition: definition, logger: logger }
+      resource_class.new(**opts)
+    end
+
+    private
+
+    def self.discover_tpr(client)
+      return unless client.respond_to? :get_third_party_resources
+      resources = client.get_third_party_resources
+      resources.each do |res| 
+        type, _, group = res.metadata.name.partition('.')
+        # TPR API supports multiple versions for a single resource :(
+        res.versions.each do |version|
+          discovered(group: group, 
+                     type: type,
+                     version: version.name,
+                     annotations: res.metadata.annotations)
+        end
+      end
+    end
+
+    def self.discover_crd(client)
+      return unless client.respond_to? :get_custom_resource_definitions
+      resources = client.get_custom_resource_definitions
+      resources.each do |res|
+        discovered(group: res.spec.group, 
+                   type: res.spec.names.kind,
+                   version: res.spec.version,
+                   annotations: res.metadata.annotations)
+      end
+    end
+
+    def self.discovered(group:, type:, version:, annotations:)
+      resource_class = Class.new(self) do
+        type = type.capitalize # TPRs are inconsistent about capitalization
+        @group = group
+        @type = type
+        @version = version
+        @prunable = DiscoverableResource.parse_bool(annotations[PRUNABLE_ANNOTATION])
+        @predeploy = DiscoverableResource.parse_bool(annotations[PREDEPLOY_ANNOTATION])
+        @timeout = DiscoverableResource.parse_timeout(type, annotations[TIMEOUT_ANNOTATION])
+
+        status_field = annotations[STATUS_FIELD_ANNOTATION]
+        success_status = annotations[STATUS_SUCCESS_ANNOTATION]
+
+        define_method 'deploy_succeeded?' do
+          getter = "get_#{type.downcase}"
+          @client ||= DiscoverableResource.kubeclient(context: @context, resource_class: self.class)
+          raw_json = @client.send(getter, @name, @namespace, as: :raw)
+          query_path = JsonPath.new(status_field)
+          current_status = query_path.first(raw_json)
+          current_status == success_status
+        end if status_field && success_status
+      end
+
+      add_resource(resource_class)
+    end
+
+    def self.add_resource(resource_class)
+      group = resource_class.group
+      type = resource_class.type
+      version = resource_class.version
+      @resources ||= {}
+      @resources[group] ||= {}
+      @resources[group][type] ||= {}
+      @resources[group][type][version] = resource_class
+    end
+
+    def self.parse_bool(value)
+      value.to_s == "true" # value could be nil
+    end
+
+    def self.parse_timeout(type, timeout)
+      begin
+        ActiveSupport::Duration.parse(timeout) if timeout
+      rescue ActiveSupport::Duration::ISO8601Parser::ParsingError
+        raise FatalDeploymentError, "Resource #{type} specified invalid timeout value '#{timeout}', must use ISO8601 duration."
+      end
+    end
+
+    def self.kubeclient(context:, resource_class:)
+     _build_kubeclient(
+        api_version: resource_class.version,
+        context: context,
+        endpoint_path: "/apis/#{resource_class.group}")
+    end
+
+    def self.v1beta1_kubeclient(context)
+      @v1beta1_kubeclient ||= build_v1beta1_kubeclient(context)
+    end
+
+    def self.v1beta1_crd_kubeclient(context)
+      @v1beta1_kubeclient_crd ||= _build_kubeclient(
+        api_version: "v1beta1",
+        context: context,
+        endpoint_path: "/apis/apiextensions.k8s.io/"
+      )
+    end
+  end
+end

lib/kubernetes-deploy/kubernetes_resource/config_map.rb

@@ -1,28 +1,6 @@
 # frozen_string_literal: true
 module KubernetesDeploy
-  class ConfigMap < KubernetesResource
+  class ConfigMap < GenericResource
     TIMEOUT = 30.seconds
-
-    def sync
-      _, _err, st = kubectl.run("get", type, @name)
-      @status = st.success? ? "Available" : "Unknown"
-      @found = st.success?
-    end
-
-    def deploy_succeeded?
-      exists?
-    end
-
-    def deploy_failed?
-      false
-    end
-
-    def timeout_message
-      UNUSUAL_FAILURE_MESSAGE
-    end
-
-    def exists?
-      @found
-    end
   end
 end

lib/kubernetes-deploy/kubernetes_resource/customresourcedefinition.rb

@@ -0,0 +1,6 @@
+# frozen_string_literal: true
+module KubernetesDeploy
+  class CustomResourceDefinition < GenericResource
+    TIMEOUT = 10.seconds
+  end
+end

lib/kubernetes-deploy/kubernetes_resource/genericresource.rb

@@ -0,0 +1,26 @@
+# frozen_string_literal: true
+module KubernetesDeploy
+  class GenericResource < KubernetesResource
+    def sync
+      _, _err, st = kubectl.run("get", type, @name)
+      @status = st.success? ? "Available" : "Unknown"
+      @found = st.success?
+    end
+
+    def deploy_succeeded?
+      exists?
+    end
+
+    def deploy_failed?
+      false
+    end
+
+    def timeout_message
+      UNUSUAL_FAILURE_MESSAGE
+    end
+
+    def exists?
+      @found
+    end
+  end
+end

lib/kubernetes-deploy/kubernetes_resource/ingress.rb

@@ -1,24 +1,6 @@
 # frozen_string_literal: true
 module KubernetesDeploy
-  class Ingress < KubernetesResource
+  class Ingress < GenericResource
     TIMEOUT = 30.seconds
-
-    def sync
-      _, _err, st = kubectl.run("get", type, @name)
-      @status = st.success? ? "Created" : "Unknown"
-      @found = st.success?
-    end
-
-    def deploy_succeeded?
-      exists?
-    end
-
-    def deploy_failed?
-      false
-    end
-
-    def exists?
-      @found
-    end
   end
 end

lib/kubernetes-deploy/kubernetes_resource/pod_disruption_budget.rb

@@ -1,29 +1,9 @@
 # frozen_string_literal: true
 module KubernetesDeploy
-  class PodDisruptionBudget < KubernetesResource
-    TIMEOUT = 10.seconds
-
-    def sync
-      _, _err, st = kubectl.run("get", type, @name)
-      @found = st.success?
-      @status = @found ? "Available" : "Unknown"
-    end
-
-    def deploy_succeeded?
-      exists?
-    end
-
+  class PodDisruptionBudget < GenericResource
     def deploy_method
       # Required until https://github.com/kubernetes/kubernetes/issues/45398 changes
       :replace_force
     end
-
-    def timeout_message
-      UNUSUAL_FAILURE_MESSAGE
-    end
-
-    def exists?
-      @found
-    end
   end
 end

lib/kubernetes-deploy/kubernetes_resource/pod_template.rb

@@ -1,26 +1,5 @@
 # frozen_string_literal: true
 module KubernetesDeploy
-  class PodTemplate < KubernetesResource
-    def sync
-      _, _err, st = kubectl.run("get", type, @name)
-      @status = st.success? ? "Available" : "Unknown"
-      @found = st.success?
-    end
-
-    def deploy_succeeded?
-      exists?
-    end
-
-    def deploy_failed?
-      false
-    end
-
-    def timeout_message
-      UNUSUAL_FAILURE_MESSAGE
-    end
-
-    def exists?
-      @found
-    end
+  class PodTemplate < GenericResource
   end
 end

lib/kubernetes-deploy/kubernetes_resource/resource_quota.rb

@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 module KubernetesDeploy
-  class ResourceQuota < KubernetesResource
+  class ResourceQuota < GenericResource
     TIMEOUT = 30.seconds
 
     def sync
@@ -17,17 +17,5 @@ def sync
     def deploy_succeeded?
       @rollout_data.dig("spec", "hard") == @rollout_data.dig("status", "hard")
     end
-
-    def deploy_failed?
-      false
-    end
-
-    def timeout_message
-      UNUSUAL_FAILURE_MESSAGE
-    end
-
-    def exists?
-      @found
-    end
   end
 end

lib/kubernetes-deploy/kubernetes_resource/thirdpartyresource.rb

@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+module KubernetesDeploy
+  class ThirdPartyResource < GenericResource
+    TIMEOUT = 30.seconds
+
+    def exists?
+      # TPRs take time to become available.
+      _, _err, st = kubectl.run("get", @name)
+      st.success?
+    end
+  end
+end