From 0ea8dd7c4529f094ee973ca55cd104336e1a05af Mon Sep 17 00:00:00 2001
From: Thorsten Eckel <te@znuny.com>
Date: Tue, 9 Jan 2018 19:23:23 +0100
Subject: [PATCH] Fixed issue #1740 - Exchange is limited to 1000 entries and
 wont sync more.

---
 .../exchange/folder_contacts/sub_sequence.rb  | 54 ++++++++++++++-----
 1 file changed, 40 insertions(+), 14 deletions(-)

diff --git a/lib/sequencer/unit/import/exchange/folder_contacts/sub_sequence.rb b/lib/sequencer/unit/import/exchange/folder_contacts/sub_sequence.rb
index 9b53da919..2a6248e84 100644
--- a/lib/sequencer/unit/import/exchange/folder_contacts/sub_sequence.rb
+++ b/lib/sequencer/unit/import/exchange/folder_contacts/sub_sequence.rb
@@ -13,25 +13,51 @@ class Sequencer
               return if ews_folder_ids.blank?
 
               ews_folder_ids.each do |folder_id|
-                folder       = ews_folder.find(folder_id)
-                display_path = ews_folder.display_path(folder)
-
-                sequence_resources(folder.items) do |parameters|
-
-                  item = parameters[:resource]
-
-                  logger.debug("Extracting attributes from Exchange item: #{item.get_all_properties!.inspect}")
-
-                  parameters.merge(
-                    resource:        ::Import::Exchange::ItemAttributes.extract(item),
-                    ews_folder_name: display_path,
-                  )
-                end
+                folder = ews_folder.find(folder_id)
+                paginated_item_sequence(folder)
               end
             end
 
             private
 
+            def paginated_item_sequence(folder)
+
+              total    = folder.total_count
+              per_page = 1000
+              pages    = (total.to_f / per_page.to_f).ceil
+
+              display_path = ews_folder.display_path(folder)
+              (1..pages).each do |page|
+
+                offset = (page - 1) * per_page
+
+                opts = {
+                  indexed_page_item_view: {
+                    max_entries_returned: per_page,
+                    offset:               offset,
+                    base_point:           'Beginning'
+                  }
+                }
+
+                logger.debug "Fetching and processing #{per_page} items (page: #{page}, offset: #{offset}) from Exchange folder '#{display_path}' (total: #{total})"
+
+                folder.items(opts).each do |item|
+
+                  sequence_resource(item) do |parameters|
+
+                    item = parameters[:resource]
+
+                    logger.debug "Extracting attributes from Exchange item: #{item.get_all_properties!.inspect}"
+
+                    parameters.merge(
+                      resource:        ::Import::Exchange::ItemAttributes.extract(item),
+                      ews_folder_name: display_path,
+                    )
+                  end
+                end
+              end
+            end
+
             def sequence
               'Import::Exchange::FolderContact'
             end