Contents

# frozen_string_literal: true

require 'concurrent/hash'

module KubernetesDeploy
  class ResourceCache
    def initialize(namespace, context, logger)
      @namespace = namespace
      @context = context
      @logger = logger

      @kind_fetcher_locks = Concurrent::Hash.new { |hash, key| hash[key] = Mutex.new }
      @data = Concurrent::Hash.new
      @kubectl = Kubectl.new(namespace: @namespace, context: @context, logger: @logger, log_failure_by_default: false)
    end

    def get_instance(kind, resource_name, raise_if_not_found: false)
      instance = use_or_populate_cache(kind).fetch(resource_name, {})
      if instance.blank? && raise_if_not_found
        raise KubernetesDeploy::Kubectl::ResourceNotFoundError, "Resource does not exist (used cache for kind #{kind})"
      end
      instance
    rescue KubectlError
      {}
    end

    def get_all(kind, selector = nil)
      instances = use_or_populate_cache(kind).values
      return instances unless selector

      instances.select do |r|
        labels = r.dig("metadata", "labels") || {}
        labels >= selector
      end
    rescue KubectlError
      []
    end

    private

    def statsd_tags
      { namespace: @namespace, context: @context }
    end

    def use_or_populate_cache(kind)
      @kind_fetcher_locks[kind].synchronize do
        return @data[kind] if @data.key?(kind)
        @data[kind] = fetch_by_kind(kind)
      end
    end

    def fetch_by_kind(kind)
      raw_json, _, st = @kubectl.run("get", kind, "--chunk-size=0", "--output=json", attempts: 5)
      raise KubectlError unless st.success?

      instances = {}
      JSON.parse(raw_json)["items"].each do |resource|
        resource_name = resource.dig("metadata", "name")
        instances[resource_name] = resource
      end
      instances
    end
  end
end

Version data entries

3 entries across 3 versions & 1 rubygems

Version	Path
kubernetes-deploy-0.25.0	lib/kubernetes-deploy/resource_cache.rb
kubernetes-deploy-0.24.0	lib/kubernetes-deploy/resource_cache.rb
kubernetes-deploy-0.23.0	lib/kubernetes-deploy/resource_cache.rb