fix: make location cache expire after 10 minutes

google-cloud-bigquerystorage/src/main/java/com/google/cloud/bigquery/storage/v1/StreamWriter.java

@@ -33,6 +33,8 @@
 import com.google.cloud.bigquery.storage.v1.StreamWriter.SingleConnectionOrConnectionPool.Kind;
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Preconditions;
+import com.google.common.cache.Cache;
+import com.google.common.cache.CacheBuilder;
 import com.google.errorprone.annotations.CanIgnoreReturnValue;
 import com.google.protobuf.ByteString;
 import io.grpc.Status;
@@ -48,7 +50,9 @@
 import java.util.Map.Entry;
 import java.util.Objects;
 import java.util.UUID;
+import java.util.concurrent.Callable;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ExecutionException;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.locks.Lock;
@@ -75,8 +79,15 @@ public class StreamWriter implements AutoCloseable {
   private static Pattern streamPatternDefaultStream = Pattern.compile(defaultStreamMatching);
 
   // Cache of location info for a given dataset.
-  private static Map<String, String> projectAndDatasetToLocation = new ConcurrentHashMap<>();
+  private static long LOCATION_CACHE_EXPIRE_MILLIS = 10 * 60 * 1000; // 10 minutes
 
+  private static Cache<String, String> allocateProjectLocationCache() {
+    return CacheBuilder.newBuilder()
+        .expireAfterWrite(LOCATION_CACHE_EXPIRE_MILLIS, TimeUnit.MILLISECONDS)
+        .build();
+  }
+
+  private static Cache<String, String> projectAndDatasetToLocation = allocateProjectLocationCache();
   /*
    * The identifier of stream to write to.
    */
@@ -287,26 +298,33 @@ private StreamWriter(Builder builder) throws IOException {
       if (location == null || location.isEmpty()) {
         // Location is not passed in, try to fetch from RPC
         String datasetAndProjectName = extractDatasetAndProjectName(builder.streamName);
-        location =
-            projectAndDatasetToLocation.computeIfAbsent(
-                datasetAndProjectName,
-                (key) -> {
-                  GetWriteStreamRequest writeStreamRequest =
-                      GetWriteStreamRequest.newBuilder()
-                          .setName(this.getStreamName())
-                          .setView(WriteStreamView.BASIC)
-                          .build();
-
-                  WriteStream writeStream = client.getWriteStream(writeStreamRequest);
-                  TableSchema writeStreamTableSchema = writeStream.getTableSchema();
-                  String fetchedLocation = writeStream.getLocation();
-                  log.info(
-                      String.format(
-                          "Fetched location %s for stream name %s, extracted project and dataset"
-                              + " name: %s\"",
-                          fetchedLocation, streamName, datasetAndProjectName));
-                  return fetchedLocation;
-                });
+        try {
+          location =
+              projectAndDatasetToLocation.get(
+                  datasetAndProjectName,
+                  new Callable<String>() {
+                    @Override
+                    public String call() throws Exception {
+                      GetWriteStreamRequest writeStreamRequest =
+                          GetWriteStreamRequest.newBuilder()
+                              .setName(getStreamName())
+                              .setView(WriteStreamView.BASIC)
+                              .build();
+
+                      WriteStream writeStream = client.getWriteStream(writeStreamRequest);
+                      TableSchema writeStreamTableSchema = writeStream.getTableSchema();
+                      String fetchedLocation = writeStream.getLocation();
+                      log.info(
+                          String.format(
+                              "Fetched location %s for stream name %s, extracted project and dataset"
+                                  + " name: %s\"",
+                              fetchedLocation, streamName, datasetAndProjectName));
+                      return fetchedLocation;
+                    }
+                  });
+        } catch (ExecutionException e) {
+          throw new IllegalStateException(e.getCause());
+        }
         if (location.isEmpty()) {
           throw new IllegalStateException(
               String.format(
@@ -371,6 +389,12 @@ static boolean isDefaultStream(String streamName) {
     return streamMatcher.find();
   }
 
+  @VisibleForTesting
+  static void recreateProjectLocationCache(long durationExpireMillis) {
+    LOCATION_CACHE_EXPIRE_MILLIS = durationExpireMillis;
+    projectAndDatasetToLocation = allocateProjectLocationCache();
+  }
+
   String getFullTraceId() {
     return fullTraceId;
   }

google-cloud-bigquerystorage/src/test/java/com/google/cloud/bigquery/storage/v1/StreamWriterTest.java

@@ -56,6 +56,7 @@
 import com.google.protobuf.Descriptors;
 import com.google.protobuf.Descriptors.DescriptorValidationException;
 import com.google.protobuf.Int64Value;
+import com.google.protobuf.Timestamp;
 import io.grpc.Status;
 import io.grpc.StatusRuntimeException;
 import io.opentelemetry.api.common.Attributes;
@@ -2551,4 +2552,66 @@ public void testGetDefaultStreamName() {
     assertEquals(
         "projects/projectId/datasets/datasetId/tables/tableId/_default", actualDefaultName);
   }
+
+  @Test
+  public void testLocationCacheIsHit() throws Exception {
+    WriteStream expectedResponse =
+        WriteStream.newBuilder()
+            .setName(WriteStreamName.of("[PROJECT]", "[DATASET]", "[TABLE]", "[STREAM]").toString())
+            .setCreateTime(Timestamp.newBuilder().build())
+            .setCommitTime(Timestamp.newBuilder().build())
+            .setTableSchema(TableSchema.newBuilder().build())
+            .setLocation("oklahoma")
+            .build();
+    testBigQueryWrite.addResponse(expectedResponse);
+
+    // first stream will result in call to getWriteStream for location lookup
+    StreamWriter writer1 =
+        StreamWriter.newBuilder(TEST_STREAM_1, client)
+            .setWriterSchema(createProtoSchema())
+            .setEnableConnectionPool(true)
+            .build();
+
+    // second stream will hit the location cache
+    StreamWriter writer2 =
+        StreamWriter.newBuilder(TEST_STREAM_1, client)
+            .setWriterSchema(createProtoSchema())
+            .setEnableConnectionPool(true)
+            .build();
+    assertEquals(1, testBigQueryWrite.getWriteStreamRequests().size());
+  }
+
+  @Test
+  public void testLocationCacheExpires() throws Exception {
+    // force cache to expire in 1000 millis
+    StreamWriter.recreateProjectLocationCache(1000);
+    WriteStream expectedResponse =
+        WriteStream.newBuilder()
+            .setName(WriteStreamName.of("[PROJECT]", "[DATASET]", "[TABLE]", "[STREAM]").toString())
+            .setCreateTime(Timestamp.newBuilder().build())
+            .setCommitTime(Timestamp.newBuilder().build())
+            .setTableSchema(TableSchema.newBuilder().build())
+            .setLocation("oklahoma")
+            .build();
+    testBigQueryWrite.addResponse(expectedResponse);
+    testBigQueryWrite.addResponse(expectedResponse);
+
+    // first stream will result in call to getWriteStream for location lookup
+    StreamWriter writer1 =
+        StreamWriter.newBuilder(TEST_STREAM_1, client)
+            .setWriterSchema(createProtoSchema())
+            .setEnableConnectionPool(true)
+            .build();
+
+    // force cache to expire
+    TimeUnit.SECONDS.sleep(2);
+
+    // second stream will result in call to getWriteStream for location lookup
+    StreamWriter writer2 =
+        StreamWriter.newBuilder(TEST_STREAM_1, client)
+            .setWriterSchema(createProtoSchema())
+            .setEnableConnectionPool(true)
+            .build();
+    assertEquals(2, testBigQueryWrite.getWriteStreamRequests().size());
+  }
 }