SONARPY-2889 Make PythonCpdAnalyzer thread-safe (#239)

GitOrigin-RevId: 3e2ab0dac8f289fa09018f8047f4cfc1867411f1

Author: maksim-grebeniuk-sonarsource

python-commons/src/main/java/org/sonar/plugins/python/PythonScanner.java

@@ -24,15 +24,13 @@
 import java.util.Collection;
 import java.util.Collections;
 import java.util.HashSet;
-import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.function.Supplier;
 import java.util.regex.Pattern;
-import javax.annotation.CheckForNull;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.sonar.api.SonarProduct;
@@ -81,7 +79,7 @@ public PythonScanner(
     Supplier<PythonParser> parserSupplier, PythonIndexer indexer, PythonFileConsumer architectureCallback) {
     super(context);
     this.checks = checks;
-    this.cpdAnalyzer = new PythonCpdAnalyzer(context);
+    this.cpdAnalyzer = new PythonCpdAnalyzer(context, this);
     this.parserSupplier = parserSupplier;
     this.indexer = indexer;
     this.indexer.buildOnce(context);
@@ -165,7 +163,7 @@ private PythonVisitorContext createVisitorContext(PythonInputFile inputFile, Pyt
     return visitorContext;
   }
 
-  private synchronized void pushTokens(PythonInputFile inputFile, PythonVisitorContext visitorContext) {
+  private void pushTokens(PythonInputFile inputFile, PythonVisitorContext visitorContext) {
     if (!isInSonarLint(context) && inputFile.kind() == PythonInputFile.Kind.PYTHON) {
       cpdAnalyzer.pushCpdTokens(inputFile.wrappedFile(), visitorContext);
     }
@@ -335,7 +333,7 @@ protected void reportStatistics(int numSkippedFiles, int numTotalFiles) {
       numSkippedFiles, numTotalFiles);
   }
 
-  private synchronized boolean restoreAndPushMeasuresIfApplicable(PythonInputFile inputFile) {
+  private boolean restoreAndPushMeasuresIfApplicable(PythonInputFile inputFile) {
     if (inputFile.wrappedFile().type() == InputFile.Type.TEST) {
       return true;
     }

python-commons/src/main/java/org/sonar/plugins/python/cpd/PythonCpdAnalyzer.java

@@ -43,9 +43,11 @@ public class PythonCpdAnalyzer {
   private static final Logger LOG = LoggerFactory.getLogger(PythonCpdAnalyzer.class);
 
   private final SensorContext context;
+  private final Object monitor;
 
-  public PythonCpdAnalyzer(SensorContext context) {
+  public PythonCpdAnalyzer(SensorContext context, Object monitor) {
     this.context = context;
+    this.monitor = monitor;
   }
 
   public void pushCpdTokens(InputFile inputFile, PythonVisitorContext visitorContext) {
@@ -68,7 +70,7 @@ public void pushCpdTokens(InputFile inputFile, PythonVisitorContext visitorConte
         }
       }
       saveTokensToCache(visitorContext, tokensToCache);
-      cpdTokens.save();
+      save(cpdTokens);
     }
   }
 
@@ -87,9 +89,8 @@ public boolean pushCachedCpdTokens(InputFile inputFile, CacheContext cacheContex
       NewCpdTokens cpdTokens = context.newCpdTokens().onFile(inputFile);
       tokens.forEach(tokenInfo ->
         cpdTokens.addToken(tokenInfo.startLine, tokenInfo.startLineOffset, tokenInfo.endLine, tokenInfo.endLineOffset, tokenInfo.value));
-      cpdTokens.save();
-      cacheContext.getWriteCache().copyFromPrevious(dataKey);
-      cacheContext.getWriteCache().copyFromPrevious(tableKey);
+      save(cpdTokens);
+      copyFromPrevious(cacheContext, dataKey, tableKey);
       return true;
     } catch (IOException e) {
       LOG.warn("Failed to deserialize CPD tokens ({}: {})", e.getClass().getSimpleName(), e.getMessage());
@@ -98,7 +99,7 @@ public boolean pushCachedCpdTokens(InputFile inputFile, CacheContext cacheContex
     return false;
   }
 
-  private static void saveTokensToCache(PythonVisitorContext visitorContext, List<Token> tokensToCache) {
+  private void saveTokensToCache(PythonVisitorContext visitorContext, List<Token> tokensToCache) {
     CacheContext cacheContext = visitorContext.cacheContext();
     if (!cacheContext.isCacheEnabled()) {
       return;
@@ -108,13 +109,32 @@ private static void saveTokensToCache(PythonVisitorContext visitorContext, List<
       String fileKey = visitorContext.pythonFile().key();
 
       CpdSerializer.SerializationResult result = CpdSerializer.serialize(tokensToCache);
-      cacheContext.getWriteCache().write(stringTableCacheKey(fileKey), result.stringTable);
-      cacheContext.getWriteCache().write(dataCacheKey(fileKey), result.data);
+      writeToCache(cacheContext, fileKey, result);
     } catch (Exception e) {
       LOG.warn("Could not write CPD tokens to cache ({}: {})", e.getClass().getSimpleName(), e.getMessage());
     }
   }
 
+  private void save(NewCpdTokens cpdTokens) {
+    synchronized (monitor) {
+      cpdTokens.save();
+    }
+  }
+
+  private void copyFromPrevious(CacheContext cacheContext, String dataKey, String tableKey) {
+    synchronized (monitor) {
+      cacheContext.getWriteCache().copyFromPrevious(dataKey);
+      cacheContext.getWriteCache().copyFromPrevious(tableKey);
+    }
+  }
+
+  private void writeToCache(CacheContext cacheContext, String fileKey, CpdSerializer.SerializationResult result) {
+    synchronized (monitor) {
+      cacheContext.getWriteCache().write(stringTableCacheKey(fileKey), result.stringTable);
+      cacheContext.getWriteCache().write(dataCacheKey(fileKey), result.data);
+    }
+  }
+
   private static boolean isNewLineWithIndentationChange(TokenType currentTokenType, TokenType nextTokenType) {
     return currentTokenType.equals(PythonTokenType.NEWLINE) && nextTokenType.equals(PythonTokenType.DEDENT);
   }

python-commons/src/test/java/org/sonar/plugins/python/cpd/PythonCpdAnalyzerTest.java

@@ -39,7 +39,7 @@ class PythonCpdAnalyzerTest {
 
   private static final String BASE_DIR = "src/test/resources/org/sonar/plugins/python";
   private SensorContextTester context = SensorContextTester.create(new File(BASE_DIR));
-  private PythonCpdAnalyzer cpdAnalyzer = new PythonCpdAnalyzer(context);
+  private PythonCpdAnalyzer cpdAnalyzer = new PythonCpdAnalyzer(context, new Object());
 
   @Test
   void code_chunks_2() {