PoC for parameterized status monitors

lib/kubernetes-deploy/kubernetes_resource/custom_resource.rb

@@ -1,5 +1,6 @@
 # frozen_string_literal: true
 require 'pry'
+require 'jsonpath'
 module KubernetesDeploy
   class CustomResource < KubernetesResource
     def initialize(namespace:, context:, definition:, logger:, statsd_tags: [], crd:)
@@ -13,23 +14,26 @@ def timeout
     end
 
     def deploy_succeeded?
-      if monitor_rollout?
-        condition("Ready")["status"] == "True"
-      else
-        super
+      return super unless rollout_params
+
+      rollout_params[:success_queries]&.all? do |query|
+        jsonpath_query(path: query[:path]) == query[:value]
       end
     end
 
     def deploy_failed?
-      if monitor_rollout?
-        condition("Failed")["status"] == "True"
-      else
-        super
+      return super unless rollout_params
+
+      rollout_params[:failure_queries].any? do |query|
+        jsonpath_query(path: query[:path]) == query[:value]
       end
     end
 
     def failure_message
-      condition("Failed")["message"] || "unknown error deploying #{id}"
+      messages = rollout_params[:failure_queries].map do |query|
+        jsonpath_query(path: query[:error_msg_path]) if query[:error_msg_path]
+      end.compact
+      messages.present? ? messages.join("\n") : "error deploying #{id}"
     end
 
     def id
@@ -52,8 +56,14 @@ def kind
       @definition["kind"]
     end
 
-    def monitor_rollout?
-      @crd.monitor_rollouts?
+    def rollout_params
+      @rollout_params ||= @crd.rollout_params
+    end
+
+    def jsonpath_query(path:)
+      JsonPath.new(path).first(@instance_data)
+    rescue StandardError
+      raise FatalDeploymentError, "fatal error for #{id}. Failed to parse JsonPath for #{path}"
     end
   end
 end

lib/kubernetes-deploy/kubernetes_resource/custom_resource_definition.rb

@@ -3,7 +3,7 @@ module KubernetesDeploy
   class CustomResourceDefinition < KubernetesResource
     TIMEOUT = 2.minutes
     CHILD_CR_TIMEOUT_ANNOTATION = "kubernetes-deploy.shopify.io/cr-timeout-override"
-    MONITOR_ROLLOUT_ANNOTATION = "kubernetes-deploy.shopify.io/monitor-rollout"
+    ROLLOUT_PARAMS_ANNOTATION = "kubernetes-deploy.shopify.io/cr-rollout-params"
     GLOBAL = true
 
     def deploy_succeeded?
@@ -47,12 +47,24 @@ def timeout_for_children
       @definition.dig("metadata", "annotations", CHILD_CR_TIMEOUT_ANNOTATION)&.to_i
     end
 
-    def monitor_rollouts?
-      @definition.dig("metadata", "annotations", MONITOR_ROLLOUT_ANNOTATION) == "true"
+    def rollout_params
+      return nil unless rollout_params_string
+
+      params = JSON.parse(rollout_params_string)
+      {
+        success_queries: params["success_queries"] || default_success_query,
+        failure_queries: params["failure_queries"] || default_failure_query,
+      }.deep_symbolize_keys
+    rescue JSON::ParserError
+      raise FatalDeploymentError, "custom rollout params are not valid JSON: '#{rollout_params_string}'"
     end
 
     private
 
+    def rollout_params_string
+      @definition.dig("metadata", "annotations", ROLLOUT_PARAMS_ANNOTATION)
+    end
+
     def names_accepted_condition
       conditions = @instance_data.dig("status", "conditions") || []
       conditions.detect { |c| c["type"] == "NamesAccepted" } || {}
@@ -61,5 +73,17 @@ def names_accepted_condition
     def names_accepted_status
       names_accepted_condition["status"]
     end
+
+    def default_success_query
+      [{ path: '$.status.Conditions[?(@.type == "Ready")].status', value: "True" }]
+    end
+
+    def default_failure_query
+      [{
+        path: '$.status.Conditions[?(@.type == "Failed")].status',
+        value: "True",
+        error_msg_path: '$.status.Conditions[?(@.type == "Failed")].message'
+      }]
+    end
   end
 end