Google Cloud Java Client
==========================
Java idiomatic client for [Google Cloud Platform][cloud-platform] services.
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- [Homepage] (https://googlecloudplatform.github.io/gcloud-java/)
- [API Documentation] (http://googlecloudplatform.github.io/gcloud-java/apidocs)
This client supports the following Google Cloud Platform services:
- [Google Cloud BigQuery] (#google-cloud-bigquery-alpha) (Alpha)
- [Google Cloud Datastore] (#google-cloud-datastore)
- [Google Cloud Resource Manager] (#google-cloud-resource-manager-alpha) (Alpha)
- [Google Cloud Storage] (#google-cloud-storage)
> Note: This client is a work-in-progress, and may occasionally
> make backwards-incompatible changes.
Quickstart
----------
If you are using Maven, add this to your pom.xml file
```xml
com.google.gcloud
gcloud-java
0.1.4
```
If you are using Gradle, add this to your dependencies
```Groovy
compile 'com.google.gcloud:gcloud-java:0.1.4'
```
If you are using SBT, add this to your dependencies
```Scala
libraryDependencies += "com.google.gcloud" % "gcloud-java" % "0.1.4"
```
Example Applications
--------------------
- [`BigQueryExample`](./gcloud-java-examples/src/main/java/com/google/gcloud/examples/bigquery/BigQueryExample.java) - A simple command line interface providing some of Cloud BigQuery's functionality
- Read more about using this application on the [`gcloud-java-examples` docs page](http://googlecloudplatform.github.io/gcloud-java/apidocs/?com/google/gcloud/examples/BigQueryExample.html).
- [`Bookshelf`](https://github.com/GoogleCloudPlatform/getting-started-java/tree/master/bookshelf) - An App Engine app that manages a virtual bookshelf.
- This app uses `gcloud-java` to interface with Cloud Datastore and Cloud Storage. It also uses Cloud SQL, another Google Cloud Platform service.
- [`DatastoreExample`](./gcloud-java-examples/src/main/java/com/google/gcloud/examples/datastore/DatastoreExample.java) - A simple command line interface for the Cloud Datastore
- Read more about using this application on the [`gcloud-java-examples` docs page](http://googlecloudplatform.github.io/gcloud-java/apidocs/?com/google/gcloud/examples/DatastoreExample.html).
- [`ResourceManagerExample`](./gcloud-java-examples/src/main/java/com/google/gcloud/examples/resourcemanager/ResourceManagerExample.java) - A simple command line interface providing some of Cloud Resource Manager's functionality
- Read more about using this application on the [`gcloud-java-examples` docs page](http://googlecloudplatform.github.io/gcloud-java/apidocs/?com/google/gcloud/examples/ResourceManagerExample.html).
- [`SparkDemo`](https://github.com/GoogleCloudPlatform/java-docs-samples/blob/master/managed_vms/sparkjava) - An example of using gcloud-java-datastore from within the SparkJava and App Engine Managed VM frameworks.
- Read about how it works on the example's [README page](https://github.com/GoogleCloudPlatform/java-docs-samples/tree/master/managed_vms/sparkjava#how-does-it-work).
- [`StorageExample`](./gcloud-java-examples/src/main/java/com/google/gcloud/examples/storage/StorageExample.java) - A simple command line interface providing some of Cloud Storage's functionality
- Read more about using this application on the [`gcloud-java-examples` docs page](http://googlecloudplatform.github.io/gcloud-java/apidocs/?com/google/gcloud/examples/StorageExample.html).
Specifying a Project ID
-----------------------
Most `gcloud-java` libraries require a project ID. There are multiple ways to specify this project ID.
1. When using `gcloud-java` libraries from within Compute/App Engine, there's no need to specify a project ID. It is automatically inferred from the production environment.
2. When using `gcloud-java` elsewhere, you can do one of the following:
* Supply the project ID when building the service options. For example, to use Datastore from a project with ID "PROJECT_ID", you can write:
```java
Datastore datastore = DatastoreOptions.builder().projectId("PROJECT_ID").build().service();
```
* Specify the environment variable `GCLOUD_PROJECT` to be your desired project ID.
* Set the project ID using the [Google Cloud SDK](https://cloud.google.com/sdk/?hl=en). To use the SDK, [download the SDK](https://cloud.google.com/sdk/?hl=en) if you haven't already, and set the project ID from the command line. For example:
```
gcloud config set project PROJECT_ID
```
`gcloud-java` determines the project ID from the following sources in the listed order, stopping once it finds a value:
1. Project ID supplied when building the service options
2. Project ID specified by the environment variable `GCLOUD_PROJECT`
3. App Engine project ID
4. Google Cloud SDK project ID
5. Compute Engine project ID
Authentication
--------------
First, ensure that the necessary Google Cloud APIs are enabled for your project. To do this, follow the instructions on the [authentication document](https://github.com/GoogleCloudPlatform/gcloud-common/blob/master/authentication/readme.md#authentication) shared by all the gcloud language libraries.
Next, choose a method for authenticating API requests from within your project:
1. When using `gcloud-java` libraries from within Compute/App Engine, no additional authentication steps are necessary.
2. When using `gcloud-java` libraries elsewhere, there are two options:
* [Generate a JSON service account key](https://cloud.google.com/storage/docs/authentication?hl=en#service_accounts). After downloading that key, you must do one of the following:
* Define the environment variable GOOGLE_APPLICATION_CREDENTIALS to be the location of the key. For example:
```bash
export GOOGLE_APPLICATION_CREDENTIALS=/path/to/my/key.json
```
* Supply the JSON credentials file when building the service options. For example, this Storage object has the necessary permissions to interact with your Google Cloud Storage data:
```java
Storage storage = StorageOptions.builder()
.authCredentials(AuthCredentials.createForJson(new FileInputStream("/path/to/my/key.json"))
.build()
.service();
```
* If running locally for development/testing, you can use use Google Cloud SDK. Download the SDK if you haven't already, then login using the SDK (`gcloud auth login` in command line). Be sure to set your project ID as described above.
`gcloud-java` looks for credentials in the following order, stopping once it finds credentials:
1. Credentials supplied when building the service options
2. App Engine credentials
3. Key file pointed to by the GOOGLE_APPLICATION_CREDENTIALS environment variable
4. Google Cloud SDK credentials
5. Compute Engine credentials
Google Cloud BigQuery (Alpha)
----------------------
- [API Documentation][bigquery-api]
- [Official Documentation][cloud-bigquery-docs]
#### Preview
Here is a code snippet showing a simple usage example from within Compute/App Engine. Note that you
must [supply credentials](#authentication) and a project ID if running this snippet elsewhere.
Complete source code can be found at
[CreateTableAndLoadData.java](./gcloud-java-examples/src/main/java/com/google/gcloud/examples/bigquery/snippets/CreateTableAndLoadData.java).
```java
import com.google.gcloud.bigquery.BigQuery;
import com.google.gcloud.bigquery.BigQueryOptions;
import com.google.gcloud.bigquery.Field;
import com.google.gcloud.bigquery.FormatOptions;
import com.google.gcloud.bigquery.Job;
import com.google.gcloud.bigquery.Schema;
import com.google.gcloud.bigquery.StandardTableDefinition;
import com.google.gcloud.bigquery.Table;
import com.google.gcloud.bigquery.TableId;
import com.google.gcloud.bigquery.TableInfo;
BigQuery bigquery = BigQueryOptions.defaultInstance().service();
TableId tableId = TableId.of("dataset", "table");
Table table = bigquery.getTable(tableId);
if (table == null) {
System.out.println("Creating table " + tableId);
Field integerField = Field.of("fieldName", Field.Type.integer());
Schema schema = Schema.of(integerField);
table = bigquery.create(TableInfo.of(tableId, StandardTableDefinition.of(schema)));
}
System.out.println("Loading data into table " + tableId);
Job loadJob = table.load(FormatOptions.csv(), "gs://bucket/path");
while (!loadJob.isDone()) {
Thread.sleep(1000L);
}
if (loadJob.status().error() != null) {
System.out.println("Job completed with errors");
} else {
System.out.println("Job succeeded");
}
```
Google Cloud Datastore
----------------------
- [API Documentation][datastore-api]
- [Official Documentation][cloud-datastore-docs]
*Follow the [activation instructions][cloud-datastore-activation] to use the Google Cloud Datastore API with your project.*
#### Preview
Here are two code snippets showing simple usage examples from within Compute/App Engine. Note that you must [supply credentials](#authentication) and a project ID if running this snippet elsewhere.
The first snippet shows how to create a Datastore entity. Complete source code can be found at
[CreateEntity.java](./gcloud-java-examples/src/main/java/com/google/gcloud/examples/datastore/snippets/CreateEntity.java).
```java
import com.google.gcloud.datastore.Datastore;
import com.google.gcloud.datastore.DatastoreOptions;
import com.google.gcloud.datastore.DateTime;
import com.google.gcloud.datastore.Entity;
import com.google.gcloud.datastore.Key;
import com.google.gcloud.datastore.KeyFactory;
Datastore datastore = DatastoreOptions.defaultInstance().service();
KeyFactory keyFactory = datastore.newKeyFactory().kind("keyKind");
Key key = keyFactory.newKey("keyName");
Entity entity = Entity.builder(key)
.set("name", "John Doe")
.set("age", 30)
.set("access_time", DateTime.now())
.build();
datastore.put(entity);
```
The second snippet shows how to update a Datastore entity if it exists. Complete source code can be
found at
[UpdateEntity.java](./gcloud-java-examples/src/main/java/com/google/gcloud/examples/datastore/snippets/UpdateEntity.java).
```java
import com.google.gcloud.datastore.Datastore;
import com.google.gcloud.datastore.DatastoreOptions;
import com.google.gcloud.datastore.DateTime;
import com.google.gcloud.datastore.Entity;
import com.google.gcloud.datastore.Key;
import com.google.gcloud.datastore.KeyFactory;
Datastore datastore = DatastoreOptions.defaultInstance().service();
KeyFactory keyFactory = datastore.newKeyFactory().kind("keyKind");
Key key = keyFactory.newKey("keyName");
Entity entity = datastore.get(key);
if (entity != null) {
System.out.println("Updating access_time for " + entity.getString("name"));
entity = Entity.builder(entity)
.set("access_time", DateTime.now())
.build();
datastore.update(entity);
}
```
Google Cloud Resource Manager (Alpha)
----------------------
- [API Documentation][resourcemanager-api]
- [Official Documentation][cloud-resourcemanager-docs]
#### Preview
Here is a code snippet showing a simple usage example. Note that you must supply Google SDK credentials for this service, not other forms of authentication listed in the [Authentication section](#authentication).
Complete source code can be found at
[UpdateAndListProjects.java](./gcloud-java-examples/src/main/java/com/google/gcloud/examples/resourcemanager/snippets/UpdateAndListProjects.java).
```java
import com.google.gcloud.resourcemanager.Project;
import com.google.gcloud.resourcemanager.ResourceManager;
import com.google.gcloud.resourcemanager.ResourceManagerOptions;
import java.util.Iterator;
ResourceManager resourceManager = ResourceManagerOptions.defaultInstance().service();
Project project = resourceManager.get("some-project-id"); // Use an existing project's ID
if (project != null) {
Project newProject = project.toBuilder()
.addLabel("launch-status", "in-development")
.build()
.replace();
System.out.println("Updated the labels of project " + newProject.projectId()
+ " to be " + newProject.labels());
}
Iterator projectIterator = resourceManager.list().iterateAll();
System.out.println("Projects I can view:");
while (projectIterator.hasNext()) {
System.out.println(projectIterator.next().projectId());
}
```
Google Cloud Storage
----------------------
- [API Documentation][storage-api]
- [Official Documentation][cloud-storage-docs]
*Follow the [activation instructions][cloud-storage-activation] to use the Google Cloud Storage API with your project.*
#### Preview
Here are two code snippets showing simple usage examples from within Compute/App Engine. Note that you must [supply credentials](#authentication) and a project ID if running this snippet elsewhere.
The first snippet shows how to create a Storage blob. Complete source code can be found at
[CreateBlob.java](./gcloud-java-examples/src/main/java/com/google/gcloud/examples/storage/snippets/CreateBlob.java).
```java
import static java.nio.charset.StandardCharsets.UTF_8;
import com.google.gcloud.storage.Blob;
import com.google.gcloud.storage.BlobId;
import com.google.gcloud.storage.BlobInfo;
import com.google.gcloud.storage.Storage;
import com.google.gcloud.storage.StorageOptions;
Storage storage = StorageOptions.defaultInstance().service();
BlobId blobId = BlobId.of("bucket", "blob_name");
BlobInfo blobInfo = BlobInfo.builder(blobId).contentType("text/plain").build();
Blob blob = storage.create(blobInfo, "Hello, Cloud Storage!".getBytes(UTF_8));
```
The second snippet shows how to update a Storage blob if it exists. Complete source code can be
found at
[UpdateBlob.java](./gcloud-java-examples/src/main/java/com/google/gcloud/examples/storage/snippets/UpdateBlob.java).
```java
import static java.nio.charset.StandardCharsets.UTF_8;
import com.google.gcloud.storage.Blob;
import com.google.gcloud.storage.BlobId;
import com.google.gcloud.storage.Storage;
import com.google.gcloud.storage.StorageOptions;
import java.nio.ByteBuffer;
import java.nio.channels.WritableByteChannel;
Storage storage = StorageOptions.defaultInstance().service();
BlobId blobId = BlobId.of("bucket", "blob_name");
Blob blob = storage.get(blobId);
if (blob != null) {
byte[] prevContent = blob.content();
System.out.println(new String(prevContent, UTF_8));
WritableByteChannel channel = blob.writer();
channel.write(ByteBuffer.wrap("Updated content".getBytes(UTF_8)));
channel.close();
}
```
Troubleshooting
---------------
To get help, follow the `gcloud-java` links in the `gcloud-*` [shared Troubleshooting document](https://github.com/GoogleCloudPlatform/gcloud-common/blob/master/troubleshooting/readme.md#troubleshooting).
Java Versions
-------------
Java 7 or above is required for using this client.
Testing
-------
This library provides tools to help write tests for code that uses gcloud-java services.
See [TESTING] to read more about using our testing helpers.
Versioning
----------
This library follows [Semantic Versioning] (http://semver.org/).
It is currently in major version zero (``0.y.z``), which means that anything
may change at any time and the public API should not be considered
stable.
Contributing
------------
Contributions to this library are always welcome and highly encouraged.
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.
License
-------
Apache 2.0 - See [LICENSE] for more information.
[CONTRIBUTING]:https://github.com/GoogleCloudPlatform/gcloud-java/blob/master/CONTRIBUTING.md
[code-of-conduct]:https://github.com/GoogleCloudPlatform/gcloud-java/blob/master/CODE_OF_CONDUCT.md#contributor-code-of-conduct
[LICENSE]: https://github.com/GoogleCloudPlatform/gcloud-java/blob/master/LICENSE
[TESTING]: https://github.com/GoogleCloudPlatform/gcloud-java/blob/master/TESTING.md
[cloud-platform]: https://cloud.google.com/
[cloud-datastore]: https://cloud.google.com/datastore/docs
[cloud-datastore-docs]: https://cloud.google.com/datastore/docs
[cloud-datastore-activation]: https://cloud.google.com/datastore/docs/activate
[datastore-api]: http://googlecloudplatform.github.io/gcloud-java/apidocs/index.html?com/google/gcloud/datastore/package-summary.html
[cloud-pubsub]: https://cloud.google.com/pubsub/
[cloud-pubsub-docs]: https://cloud.google.com/pubsub/docs
[cloud-storage]: https://cloud.google.com/storage/
[cloud-storage-docs]: https://cloud.google.com/storage/docs/overview
[cloud-storage-create-bucket]: https://cloud.google.com/storage/docs/cloud-console#_creatingbuckets
[cloud-storage-activation]: https://cloud.google.com/storage/docs/signup
[storage-api]: http://googlecloudplatform.github.io/gcloud-java/apidocs/index.html?com/google/gcloud/storage/package-summary.html
[resourcemanager-api]:http://googlecloudplatform.github.io/gcloud-java/apidocs/index.html?com/google/gcloud/resourcemanager/package-summary.html
[cloud-resourcemanager-docs]:https://cloud.google.com/resource-manager/
[cloud-bigquery]: https://cloud.google.com/bigquery/
[cloud-bigquery-docs]: https://cloud.google.com/bigquery/docs/overview
[bigquery-api]: http://googlecloudplatform.github.io/gcloud-java/apidocs/index.html?com/google/gcloud/bigquery/package-summary.html