Index: openacs-4/packages/news-aggregator/tcl/source-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/news-aggregator/tcl/source-procs.tcl,v
diff -u -r1.18 -r1.19
--- openacs-4/packages/news-aggregator/tcl/source-procs.tcl	2 Apr 2019 09:40:30 -0000	1.18
+++ openacs-4/packages/news-aggregator/tcl/source-procs.tcl	2 Apr 2019 09:53:53 -0000	1.19
@@ -147,38 +147,14 @@
         return
     }
 
-    # First we assemble a list of arrays of:
-    #       feed_url, guid
-    # Then we fetch the guids that we want to deal with
-    # Finally, we insert those.
-    set guids [list]
+    set source_updated_p false
     foreach item $items {
-        lappend guids [news_aggregator::source::generate_guid \
-                           -link        [dict get $item link] \
-                           -feed_url    $feed_url \
-                           -title       [dict get $item title] \
-                           -description [dict get $item description] \
-                           -guid        [dict get $item guid]]
-    }
-
-    set existing_items [dict create]
-    set guids '[join $guids "', '"]'
-    db_foreach items [subst {
-        select  guid, i.title, i.description
-        from    na_items i join
-                na_sources s on (i.source_id = s.source_id)
-        where   s.feed_url = :feed_url
-        and     guid in ($guids)
-    }] {
-        dict set existing_items $guid [list $title $description]
-        ns_log Debug "source::update: existing guid $guid\n\ttitle = $title"
-    }
-
-    ns_log Debug "source::update: existing_guids = [dict keys $existing_items]"
-
-    set no_items 0
-    set updated_p false
-    foreach item $items {
+        set guid [news_aggregator::source::generate_guid \
+                      -link        [dict get $item link] \
+                      -feed_url    $feed_url \
+                      -title       [dict get $item title] \
+                      -description [dict get $item description] \
+                      -guid        [dict get $item guid]]
         set title [string_truncate -len 500 -- [dict get $item title]]
         set link [string_truncate -len 500 -- [dict get $item link]]
         set original_guid [string_truncate -len 500 -- [dict get $item guid]]
@@ -191,44 +167,46 @@
             set pub_date [clock format $pub_date -format "%Y-%m-%d %T UTC"]
         }
 
-        set guid [news_aggregator::source::generate_guid \
-                      -link [dict get $item link] \
-                      -feed_url $feed_url \
-                      -title [dict get $item title] \
-                      -description [dict get $item description] \
-                      -guid [dict get $item guid]]
-
-        set new_p [expr {![dict exists $existing_items $guid]}]
-        if {$new_p} {
-            ns_log Debug "source::update: guid $guid marked as new"
-        } else {
-            lassign [dict get $existing_items $guid] db_title db_description
-            ns_log Debug "source::update: guid $guid marked as existing\ttitle = $db_title\tdescription = $db_description"
-        }
-
-        if { $new_p || $db_title ne $title || $db_description ne $description } {
-            set updated_p true
-            ns_log Debug "source::update: guid $guid marked as existing but updated; title=!$title! description=!$description!"
-            if { !$new_p } {
-                ns_log Debug "source::update:\tdb_title=!$db_title! db_description=!$db_description!"
-                ns_log Debug "source::update:\tfirst_equal=[string equal $db_title $title] second_equal=[string equal $db_description $description] new_p=$new_p item_title=[string length $title] chars db_title=[string length $db_title] chars"
+        # Notice: we are assuming source_id,guid is a superkey of
+        # na_items. This is not technically true, but this upgrade
+        # strategy should enforce it.
+        set item_exists_p [db_0or1row get_existing_news_item {
+            select title as existing_title, description as existing_description, link as existing_link
+            from na_items
+            where source_id = :source_id
+            and guid = :guid
+        }]
+        if {$item_exists_p} {
+            set item_updated_p [expr {$title ne $existing_title ||
+                                      $description ne $existing_description ||
+                                      $link ne $existing_link}]
+            if {$item_updated_p} {
+                db_dml update_news_item {
+                    update na_items set
+                    title = :title,
+                    description = :description,
+                    link = :link
+                    where source_id = :source_id
+                    and guid = :guid
+                }
+                ns_log Debug "source::update: news item $source_id.$guid updated"
             } else {
-                ns_log Debug "source::update: guid $guid is new and will be inserted; title=$title description=$description"
+                ns_log Debug "source::update: news item $source_id.$guid found and skipped"
             }
-
-            db_exec_plsql add_item {}
-            incr no_items
         } else {
-            ns_log Debug "source::update: guid $guid marked as existing and not updated"
+            db_exec_plsql add_item {}
+            ns_log Debug "source::update: news item $source_id.$guid created"
         }
+
+        set source_updated_p [expr {$source_updated_p || !$item_exists_p || $item_updated_p}]
     }
 
     set channel [dict get $result channel]
     set link        [dict get $channel link]
     set title       [dict get $channel title]
     set description [dict get $channel description]
 
-    if { $updated_p } {
+    if { $source_updated_p } {
         db_dml update_source {
             update na_sources set
                 link = :link,
@@ -240,6 +218,7 @@
                 last_modified_stamp = current_timestamp
             where source_id = :source_id
         }
+        ns_log Debug "source::update: news source $source_id updated"
     } else {
         db_dml update_source_no_new {
             update na_sources set
@@ -249,6 +228,7 @@
 	        description = :description
 	     where source_id = :source_id
         }
+        ns_log Debug "source::update: news source $source_id not updated"
     }
 }