Java idiomatic client for [Stackdriver Logging][stackdriver-logging].

[](https://www.codacy.com/app/mziccard/gcloud-java)

[](https://www.versioneye.com/user/projects/56bd8ee72a29ed002d2b0969)

Standard. `gcloud-java-logging` will work on App Engine Flexible.

<version>0.2.4</version>

If you are using Gradle, add this to your dependencies

If you are using SBT, add this to your dependencies

libraryDependencies += "com.google.cloud" % "gcloud-java-logging" % "0.2.4"

is a simple command line interface that provides some of Stackdriver Logging's functionality. Read

more about using the application on the

[`LoggingExample` docs page](http://googlecloudplatform.github.io/gcloud-java/apidocs/?com/google/cloud/examples/logging/LoggingExample.html).

About Stackdriver Logging

[Stackdriver Logging][stackdriver-logging] allows you to store, search, analyze, monitor, and alert

on log data and events from Google Cloud Platform and Amazon Web Services (AWS). Logging is a

fully-managed service that performs at scale and can ingest application and system log data from

thousands of VMs. Even better, you can analyze all that log data in real-time.

See the [Stackdriver Logging docs][stackdriver-logging-quickstart] for more details on how to

activate Logging for your project.

See the ``gcloud-java`` API [Logging documentation][logging-api] to learn how to interact with the

Stackdriver Logging using this Client Library.

Getting Started

For this tutorial, you will need a

[Google Developers Console](https://console.developers.google.com/) project with the Logging API

enabled. You will need to [enable billing](https://support.google.com/cloud/answer/6158867?hl=en) to

use Stackdriver Logging.

[Follow these instructions](https://cloud.google.com/docs/authentication#preparation) to get your

project set up. You will also need to set up the local development environment by [installing the

Google Cloud SDK](https://cloud.google.com/sdk/) and running the following commands in command line:

`gcloud auth login` and `gcloud config set project [YOUR PROJECT ID]`.

You'll need to obtain the `gcloud-java-logging` library. See the [Quickstart](#quickstart) section

to add `gcloud-java-logging` as a dependency in your code.

To make authenticated requests to Stackdriver Logging, you must create a service object with

credentials. You can then make API calls by calling methods on the Logging service object. The

simplest way to authenticate is to use

[Application Default Credentials](https://developers.google.com/identity/protocols/application-default-credentials).

These credentials are automatically inferred from your environment, so you only need the following

code to create your service object:

import com.google.cloud.logging.Logging;

import com.google.cloud.logging.LoggingOptions;

LoggingOptions options = LoggingOptions.defaultInstance();

try(Logging logging = options.service()) {

// use logging here

}

For other authentication options, see the

[Authentication](https://github.com/GoogleCloudPlatform/gcloud-java#authentication) page.

With Logging you can create logs-based metrics. Logs-based metrics allow to keep track of the number

of log messages associated to specific events. Add the following imports at the top of your file:

import com.google.cloud.logging.Metric;

import com.google.cloud.logging.MetricInfo;

Then, to create the metric, use the following code:

MetricInfo metricInfo = MetricInfo.builder("test-metric", "severity >= ERROR")

.description("Log entries with severity higher or equal to ERROR")

.build();

logging.create(metricInfo);

With Logging you can also write custom log entries. Add the following imports at the top of your

file:

import com.google.cloud.MonitoredResource;

import com.google.cloud.logging.LogEntry;

import com.google.cloud.logging.Logging;

import com.google.cloud.logging.Payload.StringPayload;

import java.util.Collections;

Then, to write the log entries, use the following code:

LogEntry firstEntry = LogEntry.builder(StringPayload.of("message"))

.logName("test-log")

.resource(MonitoredResource.builder("global")

.addLabel("project_id", options.projectId())

.build())

.build();

logging.write(Collections.singleton(firstEntry));

You can also register a `LoggingHandler` to a `java.util.logging.Logger` that publishes log entries

to Stackdriver Logging. Given the following logger:

private final static Logger LOGGER = Logger.getLogger(MyClass.class.getName());

You can register a `LoggingHandler` with the code:

LoggingHandler.addHandler(LOGGER, new LoggingHandler());

After that, logs generated using `LOGGER` will be also directed to Stackdriver Logging.

Notice that you can also register a `LoggingHandler` via the `logging.properties` configuration

file. Adding, for instance, the following line:

In

[CreateAndListMetrics.java](../gcloud-java-examples/src/main/java/com/google/cloud/examples/logging/snippets/CreateAndListMetrics.java),

[WriteAndListLogEntries.java](../gcloud-java-examples/src/main/java/com/google/cloud/examples/logging/snippets/WriteAndListLogEntries.java)

and

[AddLoggingHandler.java](../gcloud-java-examples/src/main/java/com/google/cloud/examples/logging/snippets/AddLoggingHandler.java)

we put together all the code shown above into three programs. The programs assume that you are

running on Compute Engine or from your own desktop.

This library has tools to help make tests for code using Stackdriver Logging.

See [TESTING] to read more about testing.

See `gcloud-java`'s [CONTRIBUTING] documentation and the `gcloud-*` [shared documentation](https://github.com/GoogleCloudPlatform/gcloud-common/blob/master/contributing/readme.md#how-to-contribute-to-gcloud) for more information on how to get started.

Please note that this project is released with a Contributor Code of Conduct. By participating in this project you agree to abide by its terms. See [Code of Conduct][code-of-conduct] for more information.

[code-of-conduct]:https://github.com/GoogleCloudPlatform/gcloud-java/blob/master/CODE_OF_CONDUCT.md#contributor-code-of-conduct

[TESTING]: https://github.com/GoogleCloudPlatform/gcloud-java/blob/master/TESTING.md#testing-code-that-uses-logging

[stackdriver-logging]: https://cloud.google.com/logging

[stackdriver-logging-quickstart]: https://cloud.google.com/logging/docs/quickstart-sdk

[logging-api]: http://googlecloudplatform.github.io/gcloud-java/apidocs/index.html?com/google/cloud/logging/package-summary.html