From 59682b5ba663cbc094279a3a18c76ecac2732d7b Mon Sep 17 00:00:00 2001
From: jendib <benjamin.gam@gmail.com>
Date: Tue, 1 Mar 2016 23:52:15 +0100
Subject: [PATCH] Closes #62: logs for index checking, explicit commit on close

---
 docs-core/pom.xml                             |  6 ++++
 .../docs/core/service/IndexingService.java    | 32 +++++++++++--------
 .../sismics/docs/core/util/LuceneUtil.java    |  5 ++-
 docs-parent/pom.xml                           |  6 ++++
 4 files changed, 35 insertions(+), 14 deletions(-)

diff --git a/docs-core/pom.xml b/docs-core/pom.xml
index 9e12d3fb..ed0673dc 100644
--- a/docs-core/pom.xml
+++ b/docs-core/pom.xml
@@ -93,6 +93,12 @@
       <artifactId>lucene-queryparser</artifactId>
     </dependency>
     
+    <!-- Only there to read old index and rebuild them -->
+    <dependency>
+      <groupId>org.apache.lucene</groupId>
+      <artifactId>lucene-backward-codecs</artifactId>
+    </dependency>
+    
     <dependency>
       <groupId>org.imgscalr</groupId>
       <artifactId>imgscalr-lib</artifactId>
diff --git a/docs-core/src/main/java/com/sismics/docs/core/service/IndexingService.java b/docs-core/src/main/java/com/sismics/docs/core/service/IndexingService.java
index 535fc26e..7f7fbeed 100644
--- a/docs-core/src/main/java/com/sismics/docs/core/service/IndexingService.java
+++ b/docs-core/src/main/java/com/sismics/docs/core/service/IndexingService.java
@@ -9,9 +9,9 @@ import org.apache.lucene.index.CheckIndex.Status;
 import org.apache.lucene.index.CheckIndex.Status.SegmentInfoStatus;
 import org.apache.lucene.index.DirectoryReader;
 import org.apache.lucene.store.Directory;
+import org.apache.lucene.store.NoLockFactory;
 import org.apache.lucene.store.RAMDirectory;
 import org.apache.lucene.store.SimpleFSDirectory;
-import org.apache.lucene.store.SingleInstanceLockFactory;
 import org.apache.lucene.util.Version;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -63,29 +63,35 @@ public class IndexingService extends AbstractScheduledService {
             Path luceneDirectory = DirectoryUtil.getLuceneDirectory();
             log.info("Using file Lucene storage: {}", luceneDirectory);
             try {
-                directory = new SimpleFSDirectory(luceneDirectory, new SingleInstanceLockFactory());
+                directory = new SimpleFSDirectory(luceneDirectory, NoLockFactory.INSTANCE);
             } catch (IOException e) {
                 log.error("Error initializing Lucene index", e);
             }
         }
         
         // Check index version and rebuild it if necessary
-        log.info("Checking index health and version");
-        try (CheckIndex checkIndex = new CheckIndex(directory)) {
-            Status status = checkIndex.checkIndex();
-            if (status.clean) {
-                for (SegmentInfoStatus segmentInfo : status.segmentInfos) {
-                    if (!segmentInfo.version.onOrAfter(Version.LATEST)) {
+        try {
+            if (DirectoryReader.indexExists(directory)) {
+                log.info("Checking index health and version");
+                try (CheckIndex checkIndex = new CheckIndex(directory)) {
+                    Status status = checkIndex.checkIndex();
+                    if (status.clean) {
+                        for (SegmentInfoStatus segmentInfo : status.segmentInfos) {
+                            if (!segmentInfo.version.onOrAfter(Version.LATEST)) {
+                                log.info("Index is old (" + segmentInfo.version + "), rebuilding");
+                                RebuildIndexAsyncEvent rebuildIndexAsyncEvent = new RebuildIndexAsyncEvent();
+                                AppContext.getInstance().getAsyncEventBus().post(rebuildIndexAsyncEvent);
+                                break;
+                            }
+                        }
+                    } else {
+                        log.info("Index is dirty, rebuilding");
                         RebuildIndexAsyncEvent rebuildIndexAsyncEvent = new RebuildIndexAsyncEvent();
                         AppContext.getInstance().getAsyncEventBus().post(rebuildIndexAsyncEvent);
-                        break;
                     }
                 }
-            } else {
-                RebuildIndexAsyncEvent rebuildIndexAsyncEvent = new RebuildIndexAsyncEvent();
-                AppContext.getInstance().getAsyncEventBus().post(rebuildIndexAsyncEvent);
             }
-        } catch (IOException e) {
+        } catch (Exception e) {
             log.error("Error checking index", e);
         }
     }
diff --git a/docs-core/src/main/java/com/sismics/docs/core/util/LuceneUtil.java b/docs-core/src/main/java/com/sismics/docs/core/util/LuceneUtil.java
index 9fcb977f..2754c533 100644
--- a/docs-core/src/main/java/com/sismics/docs/core/util/LuceneUtil.java
+++ b/docs-core/src/main/java/com/sismics/docs/core/util/LuceneUtil.java
@@ -33,6 +33,9 @@ public class LuceneUtil {
         // Standard analyzer
         IndexWriterConfig config = new IndexWriterConfig(new StandardAnalyzer());
         
+        // Automatically commit when closing this writer
+        config.setCommitOnClose(true);
+        
         // Merge sequentially, because Lucene writing is already done asynchronously 
         config.setMergeScheduler(new SerialMergeScheduler());
         
@@ -59,7 +62,7 @@ public class LuceneUtil {
         try {
             indexWriter.close();
         } catch (IOException e) {
-            log.error("Cannot close IndexWriter", e);
+            log.error("Cannot commit and close IndexWriter", e);
         }
     }
     
diff --git a/docs-parent/pom.xml b/docs-parent/pom.xml
index 54ee0aa2..c90ce97c 100644
--- a/docs-parent/pom.xml
+++ b/docs-parent/pom.xml
@@ -339,6 +339,12 @@
         <version>${org.apache.lucene.version}</version>
       </dependency>
       
+      <dependency>
+        <groupId>org.apache.lucene</groupId>
+        <artifactId>lucene-backward-codecs</artifactId>
+        <version>${org.apache.lucene.version}</version>
+      </dependency>
+      
       <dependency>
         <groupId>org.imgscalr</groupId>
         <artifactId>imgscalr-lib</artifactId>