Change open-method for external-as-topology script to eliminate conta…

…iner reload when the script was updated

lib/api/topologies/network/snapshot/external_as_topology.rb

@@ -1,6 +1,8 @@
 # frozen_string_literal: true
 
 require 'grape'
+require 'json'
+require 'open3'
 
 module NetomoxExp
   module ApiRoute
@@ -10,26 +12,17 @@ class ExternalAsTopology < Grape::API
       resource 'external_as_topology' do
         get do
           network, snapshot = %i[network snapshot].map { |key| params[key] }
-          # NOTE: to `load` topology script, it must be absolute-path
-          #   see also: https://docs.ruby-lang.org/ja/latest/method/Kernel/m/load.html
+          # NOTE: absolute-path of external_as_script
           ext_topo_dir = File.join(CONFIGS_DIR, network, snapshot, 'external_as_topology')
-          puts "# DEBUG: ext_topo_dir=#{ext_topo_dir}"
           error!("#{network}/#{snapshot} does not have external-AS topology dir", 404) unless Dir.exist?(ext_topo_dir)
 
           ext_topo_script = File.join(ext_topo_dir, 'main.rb')
           error!("External-AS topology script is not found in #{ext_topo_dir}", 404) unless File.exist?(ext_topo_script)
 
-          # param [String] script
-          # return [String] external-AS topology data (RFC8345 json string)
-          generate_topology_proc = lambda do |script|
-            # (re)load every call
-            load script
-            # the script defines `generate_topology` function that returns RFC8345 topology json string as external-AS
-            generate_topology
-          end
-
-          # response
-          generate_topology_proc.call(ext_topo_script)
+          command = "ruby #{ext_topo_script}"
+          logger.info "Call external script: #{command}"
+          output, _status = Open3.capture2(command)
+          JSON.parse(output)
         end
       end
     end