From 40565f1f32404500173e54abc48ddc3698306966 Mon Sep 17 00:00:00 2001
From: John Niang <johnniang@fastmail.com>
Date: Sat, 7 Oct 2023 05:40:45 -0500
Subject: [PATCH] Prevent Lucene search engine updates from being interrupted
 (#4681)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

#### What type of PR is this?

/kind bug
/area core

#### What this PR does / why we need it:

Lucene search engine will stop updating while the content of any post is `null`.

This PR resets the `null` content into empty string and ignore the error while updating Lucene document.

#### Which issue(s) this PR fixes:

Fixes https://github.com/halo-dev/halo/issues/4623

#### Does this PR introduce a user-facing change?

```release-note
修复因某篇文章的内容为 null 导致无法搜索部分文章的问题
```
---
 .../app/search/post/LucenePostSearchService.java    | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/application/src/main/java/run/halo/app/search/post/LucenePostSearchService.java b/application/src/main/java/run/halo/app/search/post/LucenePostSearchService.java
index 9c31c6ec3..5cfd2960b 100644
--- a/application/src/main/java/run/halo/app/search/post/LucenePostSearchService.java
+++ b/application/src/main/java/run/halo/app/search/post/LucenePostSearchService.java
@@ -1,5 +1,6 @@
 package run.halo.app.search.post;
 
+import static org.apache.commons.lang3.StringUtils.defaultString;
 import static org.apache.lucene.document.Field.Store.YES;
 import static org.apache.lucene.index.IndexWriterConfig.OpenMode.CREATE_OR_APPEND;
 
@@ -40,7 +41,6 @@ import org.apache.lucene.store.FSDirectory;
 import org.springframework.beans.factory.DisposableBean;
 import org.springframework.stereotype.Service;
 import org.springframework.util.StopWatch;
-import reactor.core.Exceptions;
 import run.halo.app.infra.properties.HaloProperties;
 import run.halo.app.search.SearchParam;
 import run.halo.app.search.SearchResult;
@@ -121,16 +121,17 @@ public class LucenePostSearchService implements PostSearchService, DisposableBea
         writeConfig.setOpenMode(CREATE_OR_APPEND);
         try (var writer = new IndexWriter(postIndexDir, writeConfig)) {
             posts.forEach(post -> {
-                var doc = this.convert(post);
                 try {
+                    var doc = this.convert(post);
                     var seqNum =
                         writer.updateDocument(new Term(PostDoc.ID_FIELD, post.name()), doc);
                     if (log.isDebugEnabled()) {
                         log.debug("Updated document({}) with sequence number {} returned",
                             post.name(), seqNum);
                     }
-                } catch (IOException e) {
-                    throw Exceptions.propagate(e);
+                } catch (Throwable e) {
+                    // Continue next update
+                    log.error("Failed to update document for post {}", post.name(), e);
                 }
             });
         }
@@ -180,8 +181,8 @@ public class LucenePostSearchService implements PostSearchService, DisposableBea
         var doc = new Document();
         doc.add(new StringField("name", post.name(), YES));
         doc.add(new TextField("title", post.title(), YES));
-        doc.add(new TextField("excerpt", post.excerpt(), YES));
-        doc.add(new TextField("content", post.content(), YES));
+        doc.add(new TextField("excerpt", defaultString(post.excerpt()), YES));
+        doc.add(new TextField("content", defaultString(post.content()), YES));
 
         var publishTimestamp = post.publishTimestamp().getEpochSecond();
         doc.add(new LongPoint("publishTimestamp", publishTimestamp));