add indexer to index authors from a blog post

src/collective/blog/indexers/configure.zcml

@@ -11,4 +11,9 @@
       name="blog_uid"
       />
 
+  <adapter
+      factory=".post.post_authors"
+      name="post_authors"
+      />
+
 </configure>

src/collective/blog/indexers/post.py

@@ -1,9 +1,26 @@
 from collective.blog.content.post import IPost
 from collective.blog.content.post import Post
+from plone import api
 from plone.indexer import indexer
 
 
 @indexer(IPost)
 def blog_post_indexer(obj: Post):
     """Return blog uuid."""
     return obj.blog_uid()
+
+
+@indexer(IPost)
+def post_authors(obj: Post):
+    """Returns the authors of a blog post."""
+    authors = []
+    uids = obj.creators
+    for uid in uids:
+        searchResult = api.content.find(portal_type="Author", UID=uid)
+        if len(searchResult) > 0:
+            author = searchResult[0].getObject()
+
+            if author is not None:
+                authors.append(author.title)
+
+    return authors

src/collective/blog/profiles/default/catalog.xml

@@ -22,4 +22,14 @@
 
   <column value="blog_uid" />
 
+  <!-- Add new index and column-->
+  <index meta_type="KeywordIndex"
+         name="post_authors"
+  >
+    <indexed_attr value="post_authors" />
+  </index>
+
+  <column value="post_authors" />
+
+
 </object>

src/collective/blog/profiles/default/metadata.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <metadata>
-  <version>1002</version>
+  <version>1003</version>
   <dependencies>
     <!-- <dependency>profile-plone.volto:default</dependency> -->
   </dependencies>

src/collective/blog/upgrades/configure.zcml

@@ -37,5 +37,19 @@
         />
   </genericsetup:upgradeSteps>
 
+  <genericsetup:upgradeSteps
+      profile="collective.blog:default"
+      source="1002"
+      destination="1003"
+      >
+    <genericsetup:upgradeDepends
+        title="Catalog: Add post_authors column and index"
+        import_steps="catalog"
+        />
+    <genericsetup:upgradeStep
+        title="Recatalog Posts"
+        handler=".v1003.recatalog_post_authors"
+        />
+  </genericsetup:upgradeSteps>
 
 </configure>

src/collective/blog/upgrades/v1003.py

@@ -0,0 +1,15 @@
+from collective.blog import logger
+from plone import api
+from Products.GenericSetup.tool import SetupTool
+
+
+def recatalog_post_authors(setup_tool: SetupTool):
+    """Recatalog Posts."""
+    with api.env.adopt_roles(["Manager"]):
+        brains = api.content.find(portal_type=["Post"])
+        total = len(brains)
+        logger.info(f"Recatalog {total} items")
+        for brain in brains:
+            obj = brain.getObject()
+            obj.reindexObject(idxs=["post_authors"])
+    logger.info("Reindexed post_authors")