Add the "publication date" default value in the blog and gleaning types

web/modules/custom/geo_upgrade/migrations/upgrade_d7_node_blog.yml

@@ -157,6 +157,17 @@ process:
         title: title
         width: width
         height: height
+  field_publication_date:
+    - plugin: publication_date_default
+      source: field_publication_date
+      method: process
+    - plugin: sub_process
+      process:
+        value:
+          plugin: format_date
+          from_format: 'Y-m-d\TH:i:s'
+          to_format: 'Y-m-d'
+          source: value
   path/alias: source_path
   path/pathauto:
     plugin: default_value

web/modules/custom/geo_upgrade/migrations/upgrade_d7_node_gleaning.yml

@@ -98,6 +98,17 @@ process:
         target_id: fid
         display: display
         description: description
+  field_publication_date:
+    - plugin: publication_date_default
+      source: field_publication_date
+      method: process
+    - plugin: sub_process
+      process:
+        value:
+          plugin: format_date
+          from_format: 'Y-m-d\TH:i:s'
+          to_format: 'Y-m-d'
+          source: value
   path/alias: source_path
   path/pathauto:
     plugin: default_value

web/modules/custom/geo_upgrade/migrations/upgrade_d7_node_issueindex.yml

@@ -173,7 +173,7 @@ process:
       process:
         value:
           plugin: format_date
-          from_format: 'U'
+          from_format: 'Y-m-d\TH:i:s'
           to_format: 'Y-m-d'
           source: value
   path/alias: source_path

web/modules/custom/geo_upgrade/src/Plugin/migrate/process/PublicationDateDefault.php

@@ -20,7 +20,7 @@ class PublicationDateDefault extends ProcessPluginBase {
    */
   public function transform($value, MigrateExecutableInterface $migrate_executable, Row $row, $destination_property) {
     $created_date = $row->getSourceProperty('created');
-    if (empty($value)) {
+    if (!isset($value) || empty($value)) {
       $value = [0 => ['value' => date('Y-m-d\TH:i:s', $created_date)]];
     }
     return $value;