#253 fix node transfer list infinite loop with once_only.

Signed-off-by: Laurent Martin <laurent.martin.l@gmail.com>

Author: laurent-martin

CHANGELOG.md

@@ -10,6 +10,8 @@ Released: [Place date of release here]
 
 ### Issues Fixed
 
+* `node`: #253 fix `node transfer list` infinite loop with `once_only`.
+
 ### Breaking Changes
 
 ## 4.25.5

lib/aspera/api/node.rb

@@ -530,32 +530,45 @@ def read_with_paging(subpath, query = nil, iteration: nil, **call_args)
         Aspera.assert_type(query, Hash, NilClass){'query'}
         Aspera.assert(!call_args.key?(:query))
         query = {} if query.nil?
-        query[:iteration_token] = iteration[0] unless iteration.nil?
+        query[:iteration_token] = iteration[0] unless iteration.nil? || iteration[0].nil?
         max = query.delete(RestList::MAX_ITEMS)
+        # Return empty list immediately if max is 0
+        return [] if max&.zero?
         item_list = []
         loop do
           data, http = read(subpath, query, **call_args, ret: :both)
           Aspera.assert_type(data, Array){"Expected data to be an Array, got: #{data.class}"}
           # no data
           break if data.empty?
-          # get next iteration token from link
-          next_iteration_token = nil
-          link_info = http['Link']
-          unless link_info.nil?
-            m = link_info.match(/<([^>]+)>/)
-            Aspera.assert(m){"Cannot parse iteration in Link: #{link_info}"}
-            next_iteration_token = Rest.query_to_h(URI.parse(m[1]).query)['iteration_token']
-          end
-          # same as last iteration: stop
-          break if next_iteration_token&.eql?(query[:iteration_token])
-          query[:iteration_token] = next_iteration_token
           item_list.concat(data)
+          # Check if we reached the max limit
           if max&.<=(item_list.length)
             item_list = item_list.slice(0, max)
             break
           end
+          # Update progress spinner
+          RestParameters.instance.spinner_cb.call(item_list.length)
+          # Parse Link header according to RFC 8288 to extract next iteration token
+          next_url = Rest.parse_link_header(http['Link'], rel: 'next')
+          next_iteration_token = nil
+          if next_url
+            begin
+              parsed_uri = URI.parse(next_url)
+              query_params = Rest.query_to_h(parsed_uri.query) if parsed_uri.query
+              next_iteration_token = query_params['iteration_token'] if query_params
+            rescue URI::InvalidURIError => e
+              Log.log.warn{"Invalid URI in Link header: #{next_url} - #{e.message}"}
+            end
+          end
+          # Stop if no next token
           break if next_iteration_token.nil?
+          # Stop if same token as current (infinite loop protection)
+          break if next_iteration_token.eql?(query[:iteration_token])
+          # Update token for next iteration
+          query[:iteration_token] = next_iteration_token
         end
+        # Signal completion
+        RestParameters.instance.spinner_cb.call(action: :success)
         # save iteration token if needed
         iteration[0] = query[:iteration_token] unless iteration.nil?
         item_list

lib/aspera/rest.rb

@@ -150,6 +150,37 @@ def query_to_h(query)
         end
       end
 
+      # Parse Link header according to RFC 8288 to extract a specific relation
+      # @param link_header [String, nil] The Link header value
+      # @param rel [String] The relation to look for (default: 'next')
+      # @return [String, nil] The URL of the link with the specified relation, or nil
+      def parse_link_header(link_header, rel: 'next')
+        return if link_header.nil? || link_header.empty?
+        # RFC 8288: Link header format is: <URI>; param1=value1; param2=value2, <URI2>; ...
+        # We look for the link with the specified rel
+        link_header.split(',').each do |link_part|
+          link_part = link_part.strip
+          # Extract URL between < and >
+          url_match = link_part.match(/<([^>]+)>/)
+          next unless url_match
+          url = url_match[1]
+          # Extract parameters after the URL
+          params_str = link_part[url_match.end(0)..-1]
+          # Check if this link has the specified rel (with or without quotes, case insensitive)
+          next unless /;\s*rel\s*=\s*"?#{Regexp.escape(rel)}"?/i.match?(params_str)
+          return url
+        end
+        # Fallback: if no rel found and looking for 'next', try the first link (backward compatibility)
+        if rel.eql?('next')
+          first_link = link_header.split(',').first&.strip
+          if first_link
+            url_match = first_link.match(/<([^>]+)>/)
+            return url_match[1] if url_match
+          end
+        end
+        nil
+      end
+
       # Start a HTTP/S session, also used for web sockets
       # @param base_url [String] Base url of HTTP/S session
       # @return [Net::HTTP] A started HTTP session

tests/tests.yml

@@ -1250,7 +1250,6 @@ nd_xfer_lstb:
     - --once-only=yes
 nd_xfer_lst_once1:
   tags:
-    - flaky
     - nodoc
   depends_on:
     - nd_xfer_lstb
@@ -1261,7 +1260,6 @@ nd_xfer_lst_once1:
     - --once-only=yes
 nd_xfer_lst_once2:
   tags:
-    - flaky
     - nodoc
   depends_on:
     - nd_xfer_lst_once1