fix: fix samples region tags and test flakiness

README.md

@@ -166,6 +166,27 @@ LogEntry firstEntry = LogEntry.newBuilder(StringPayload.of("message"))
 logging.write(Collections.singleton(firstEntry));
 ```
 
+The library supports writing log entries synchronously and asynchronously.
+In the synchronous mode each call to `write()` method results in a consequent call to Logging API to write a log entry.
+In the asynchronous mode the call(s) to Logging API takes place asynchronously and few calls to `write()` method may be batched together to compose a single call to Logging API.
+The default mode of writing is asynchronous.
+It can be configured in the `java.util.logging` handler [configuration file](https://cloud.google.com/logging/docs/setup/java#javautillogging_configuration):
+
+```
+com.google.cloud.logging.LoggingHandler.synchronicity=SYNC
+```
+
+or in the code after initiating an instance of `Logging` by calling:
+
+```java
+logging.setWriteSynchronicity(Synchronicity.SYNC);
+```
+
+NOTE:
+> Writing log entries asynchronously in some Google Cloud managed environments (e.g. Cloud Functions)
+> may lead to unexpected results such as absense of expected log entries or abnormal program execution.
+> To avoid these unexpected results, it is recommended to use synchronous mode.
+
 #### Listing log entries
 
 With Logging you can also list log entries that have been previously written. Add the following
@@ -236,6 +257,7 @@ Samples are in the [`samples/`](https://github.com/googleapis/java-logging/tree/
 | Log Entry Write Http Request | [source code](https://github.com/googleapis/java-logging/blob/master/samples/snippets/src/main/java/com/example/logging/LogEntryWriteHttpRequest.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-logging&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/logging/LogEntryWriteHttpRequest.java) |
 | Quickstart Sample | [source code](https://github.com/googleapis/java-logging/blob/master/samples/snippets/src/main/java/com/example/logging/QuickstartSample.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-logging&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/logging/QuickstartSample.java) |
 | Tail Log Entries | [source code](https://github.com/googleapis/java-logging/blob/master/samples/snippets/src/main/java/com/example/logging/TailLogEntries.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-logging&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/logging/TailLogEntries.java) |
+| Write Log Entry | [source code](https://github.com/googleapis/java-logging/blob/master/samples/snippets/src/main/java/com/example/logging/WriteLogEntry.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-logging&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/logging/WriteLogEntry.java) |
 | Quickstart | [source code](https://github.com/googleapis/java-logging/blob/master/samples/snippets/src/main/java/com/example/logging/jul/Quickstart.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-logging&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/logging/jul/Quickstart.java) |
 | Example Enhancer | [source code](https://github.com/googleapis/java-logging/blob/master/samples/snippets/src/main/java/com/example/logging/jul/enhancers/ExampleEnhancer.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-logging&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/logging/jul/enhancers/ExampleEnhancer.java) |
 

samples/snippets/src/main/java/com/example/logging/ListLogEntries.java

@@ -25,6 +25,7 @@
 import java.text.DateFormat;
 import java.text.SimpleDateFormat;
 import java.util.Calendar;
+import java.util.TimeZone;
 
 public class ListLogEntries {
 
@@ -33,33 +34,34 @@ public static void main(String[] args) throws Exception {
     // or provide it as an argument.
     String logName = args.length > 0 ? args[0] : "test-log";
 
-    LoggingOptions options = LoggingOptions.getDefaultInstance();
-    Logging logging = options.getService();
+    try (Logging logging = LoggingOptions.getDefaultInstance().getService()) {
 
-    // When composing a filter, using indexed fields, such as timestamp, resource.type, logName and
-    // others can help accelerate the results
-    // Full list of indexed fields here:
-    // https://cloud.google.com/logging/docs/view/advanced-queries#finding-quickly
-    // This sample restrict the results to only last hour to minimize number of API calls
-    Calendar calendar = Calendar.getInstance();
-    calendar.add(Calendar.HOUR, -1);
-    DateFormat rfc3339 = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
-    String logFilter =
-        "logName=projects/"
-            + options.getProjectId()
-            + "/logs/"
-            + logName
-            + " AND timestamp>=\""
-            + rfc3339.format(calendar.getTime())
-            + "\"";
+      // When composing a filter, using indexed fields, such as timestamp, resource.type, logName
+      // and
+      // others can help accelerate the results
+      // Full list of indexed fields here:
+      // https://cloud.google.com/logging/docs/view/advanced-queries#finding-quickly
+      // This sample restrict the results to only last minute to minimize number of API calls
+      Calendar calendar = Calendar.getInstance(TimeZone.getTimeZone("UTC"));
+      calendar.add(Calendar.MINUTE, -1);
+      DateFormat rfc3339 = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
+      String logFilter =
+          "logName=projects/"
+              + logging.getOptions().getProjectId()
+              + "/logs/"
+              + logName
+              + " AND timestamp>=\""
+              + rfc3339.format(calendar.getTime())
+              + "\"";
 
-    // List all log entries
-    Page<LogEntry> entries = logging.listLogEntries(EntryListOption.filter(logFilter));
-    while (entries != null) {
-      for (LogEntry logEntry : entries.iterateAll()) {
-        System.out.println(logEntry);
+      // List all log entries
+      Page<LogEntry> entries = logging.listLogEntries(EntryListOption.filter(logFilter));
+      while (entries != null) {
+        for (LogEntry logEntry : entries.iterateAll()) {
+          System.out.println(logEntry);
+        }
+        entries = entries.getNextPage();
       }
-      entries = entries.getNextPage();
     }
   }
 }

samples/snippets/src/main/java/com/example/logging/ListLogs.java

@@ -25,16 +25,16 @@ public class ListLogs {
 
   public static void main(String... args) throws Exception {
 
-    LoggingOptions options = LoggingOptions.getDefaultInstance();
-    Logging logging = options.getService();
+    try (Logging logging = LoggingOptions.getDefaultInstance().getService()) {
 
-    // List all log names
-    Page<String> logNames = logging.listLogs();
-    while (logNames != null) {
-      for (String logName : logNames.iterateAll()) {
-        System.out.println(logName);
+      // List all log names
+      Page<String> logNames = logging.listLogs();
+      while (logNames != null) {
+        for (String logName : logNames.iterateAll()) {
+          System.out.println(logName);
+        }
+        logNames = logNames.getNextPage();
       }
-      logNames = logNames.getNextPage();
     }
   }
 }

samples/snippets/src/main/java/com/example/logging/LogEntryWriteHttpRequest.java

@@ -16,7 +16,7 @@
 
 package com.example.logging;
 
-// [START logging_write_request_entry]
+// [START logging_write_log_entry_advanced]
 import com.google.cloud.MonitoredResource;
 import com.google.cloud.logging.HttpRequest;
 import com.google.cloud.logging.LogEntry;
@@ -61,4 +61,4 @@ public static void createLogEntryRequest(String logName, String payLoad, HttpReq
     }
   }
 }
-// [END logging_write_request_entry]
+// [END logging_write_log_entry_advanced]

samples/snippets/src/main/java/com/example/logging/QuickstartSample.java

@@ -37,27 +37,24 @@ public class QuickstartSample {
 
   /** Expects a new or existing Cloud log name as the first argument. */
   public static void main(String... args) throws Exception {
-
-    // Instantiates a client
-    Logging logging = LoggingOptions.getDefaultInstance().getService();
-
     // The name of the log to write to
     String logName = args[0]; // "my-log";
+    String textPayload = "Hello, world!";
 
-    // The data to write to the log
-    String text = "Hello, world!";
-
-    LogEntry entry =
-        LogEntry.newBuilder(StringPayload.of(text))
-            .setSeverity(Severity.ERROR)
-            .setLogName(logName)
-            .setResource(MonitoredResource.newBuilder("global").build())
-            .build();
-
-    // Writes the log entry asynchronously
-    logging.write(Collections.singleton(entry));
-
-    System.out.printf("Logged: %s%n", text);
+    // Instantiates a client
+    try (Logging logging = LoggingOptions.getDefaultInstance().getService()) {
+
+      LogEntry entry =
+          LogEntry.newBuilder(StringPayload.of(textPayload))
+              .setSeverity(Severity.ERROR)
+              .setLogName(logName)
+              .setResource(MonitoredResource.newBuilder("global").build())
+              .build();
+
+      // Writes the log entry asynchronously
+      logging.write(Collections.singleton(entry));
+    }
+    System.out.printf("Logged: %s%n", textPayload);
   }
 }
 // [END logging_quickstart]

samples/snippets/src/main/java/com/example/logging/WriteLogEntry.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright 2021 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example.logging;
+
+// [START logging_write_log_entry]
+import com.google.cloud.MonitoredResource;
+import com.google.cloud.logging.LogEntry;
+import com.google.cloud.logging.Logging;
+import com.google.cloud.logging.LoggingOptions;
+import com.google.cloud.logging.Payload.JsonPayload;
+import com.google.cloud.logging.Severity;
+import com.google.common.collect.ImmutableMap;
+import java.util.Collections;
+import java.util.Map;
+
+public class WriteLogEntry {
+
+  public static void main(String[] args) throws Exception {
+    // TODO(developer): Optionally provide the logname as an argument
+    String logName = args.length > 0 ? args[0] : "test-log";
+
+    // Instantiates a client
+    try (Logging logging = LoggingOptions.getDefaultInstance().getService()) {
+      Map<String, String> payload =
+          ImmutableMap.of(
+              "name", "King Arthur", "quest", "Find the Holy Grail", "favorite_color", "Blue");
+      LogEntry entry =
+          LogEntry.newBuilder(JsonPayload.of(payload))
+              .setSeverity(Severity.INFO)
+              .setLogName(logName)
+              .setResource(MonitoredResource.newBuilder("global").build())
+              .build();
+
+      logging.write(Collections.singleton(entry));
+    }
+    System.out.printf("Wrote to %s\n", logName);
+  }
+}
+// [END logging_write_log_entry]

samples/snippets/src/test/java/com/example/logging/LoggingIT.java

@@ -30,7 +30,9 @@
 import java.io.PrintStream;
 import java.util.Collections;
 import org.junit.After;
+import org.junit.AfterClass;
 import org.junit.Before;
+import org.junit.BeforeClass;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;
@@ -41,16 +43,38 @@
 public class LoggingIT {
 
   private static final String TEST_LOG = formatForTest("test-log");
-  private static final String GOOGLEAPIS_AUDIT_LOGNAME = "cloudaudit.googleapis.com%2Factivity";
   private static final String STRING_PAYLOAD = "Hello, world!";
   private static final String STRING_PAYLOAD2 = "Hello world again";
 
   private ByteArrayOutputStream bout;
   private PrintStream out;
-  private Logging logging = LoggingOptions.getDefaultInstance().getService();
+  private static Logging logging;
+
+  private void deleteLog(String logName) throws InterruptedException {
+    int deleteAttempts = 0;
+    int allowedDeleteAttempts = 5;
+    boolean deleted = false;
+    while (!deleted && deleteAttempts < allowedDeleteAttempts) {
+      deleted = logging.deleteLog(logName);
+      deleteAttempts++;
+      if (!deleted) {
+        Thread.sleep(1000);
+      }
+    }
+    if (!deleted) {
+      System.err.println(
+          "Failed to clean up log entries after 5 attempts. Following tests may be flaky...");
+    }
+  }
 
-  private void deleteLog(String logName) {
-    logging.deleteLog(logName);
+  @BeforeClass
+  public static void startup() {
+    logging = LoggingOptions.getDefaultInstance().getService();
+  }
+
+  @AfterClass
+  public static void shutDown() throws Exception {
+    logging.close();
   }
 
   @Before
@@ -61,13 +85,13 @@ public void setUp() {
   }
 
   @After
-  public void tearDown() {
+  public void tearDown() throws Exception {
     // Clean up created logs
     deleteLog(TEST_LOG);
     System.setOut(null);
   }
 
-  @Test
+  @Test(timeout = 60000)
   public void testQuickstartSample() throws Exception {
     QuickstartSample.main(TEST_LOG);
     String got = bout.toString();
@@ -116,7 +140,7 @@ public void testWriteLogHttpRequestSample() throws Exception {
     String[] args = new String[] {TEST_LOG};
     while (bout.toString().isEmpty()) {
       ListLogEntries.main(args);
-      Thread.sleep(5000);
+      Thread.sleep(1000);
     }
 
     // check log entry contain request data
@@ -125,14 +149,10 @@ public void testWriteLogHttpRequestSample() throws Exception {
   }
 
   @Test(timeout = 60000)
-  public void testListLogNamesSample() throws Exception {
-    ListLogs.main();
-    // Check for mocked STDOUT having data
-    while (bout.toString().isEmpty()) {
-      Thread.sleep(5000);
-    }
-
-    assertThat(bout.toString().contains(GOOGLEAPIS_AUDIT_LOGNAME)).isTrue();
+  public void testWriteLogEntrySample() throws Exception {
+    WriteLogEntry.main(new String[] {TEST_LOG});
+    String got = bout.toString();
+    assertThat(got).contains(String.format("Wrote to %s", TEST_LOG));
   }
 
   @Test(timeout = 60000)
@@ -153,7 +173,7 @@ public void testTailLogEntriesSample() throws Exception {
               logging.write(Collections.singleton(logEntry));
             }
           } catch (Exception t) {
-            System.out.println("Failed to write log entry:\n" + t);
+            System.err.println("Failed to write log entry:\n" + t);
           }
         };
     Thread thread = new Thread(task);