Skip to content

Commit

Permalink
Add BigQuery module README
Browse files Browse the repository at this point in the history
  • Loading branch information
mziccard committed Dec 21, 2015
1 parent 7eee528 commit bf6a3fe
Showing 1 changed file with 239 additions and 7 deletions.
246 changes: 239 additions & 7 deletions gcloud-java-bigquery/README.md
Original file line number Diff line number Diff line change
Expand Up @@ -8,16 +8,21 @@ Java idiomatic client for [Google Cloud BigQuery] (https://cloud.google.com/bigq
<!-- TODO(mziccard): add in the maven shield once the artifact is pushed to maven -->

- [Homepage] (https://googlecloudplatform.github.io/gcloud-java/)
+<!-- TODO(mziccard): add link to API documentatin -->
- [API Documentation] (http://googlecloudplatform.github.io/gcloud-java/apidocs/index.html?com/google/gcloud/bigquery/package-summary.html)

> Note: This client is a work-in-progress, and may occasionally
> make backwards-incompatible changes.
Quickstart
----------
Add this to your pom.xml file
<!-- TODO(mziccard): add dependency code -->
If you are using Maven, add this to your pom.xml file
<!-- TODO(mziccard): add mvn dependency code -->

If you are using Gradle, add this to your dependencies
<!-- TODO(mziccard): add gradle dependency code -->

If you are using SBT, add this to your dependencies
<!-- TODO(mziccard): add sbt dependency code -->

Example Application
-------------------
Expand All @@ -36,14 +41,239 @@ About Google Cloud BigQuery
Data can be streamed into BigQuery at millions of rows per second to enable real-time analysis.
With BigQuery you can easily deploy Petabyte-scale Databases.

Be sure to activate the Google Cloud BigQuery API on the Developer's Console to use BigQuery from your project.
Be sure to activate the Google Cloud BigQuery API on the Developer's Console to use BigQuery from
your project.

See the ``gcloud-java`` API [bigquery documentation][bigquery-api] to learn how to interact
with Google Cloud BigQuery using this Client Library.

Here is a code snippet showing a simple usage example from within Compute/App Engine. Note that you must [supply credentials](https://github.com/GoogleCloudPlatform/gcloud-java#authentication) and a project ID if running this snippet elsewhere.
Getting Started
---------------
#### Prerequisites
For this tutorial, you will need a
[Google Developers Console](https://console.developers.google.com/) project with the BigQuery API
enabled. You will need to [enable billing](https://support.google.com/cloud/answer/6158867?hl=en) to
use Google Cloud BigQuery.
[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]`.

#### Installation and setup
You'll need to obtain the `gcloud-java-bigquery` library. See the [Quickstart](#quickstart) section
to add `gcloud-java-bigquery` as a dependency in your code.

#### Creating an authorized service object
To make authenticated requests to Google Cloud BigQuery, you must create a service object with
credentials. You can then make API calls by calling methods on the BigQuery 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:

```java
import com.google.gcloud.bigquery.BigQuery;
import com.google.gcloud.bigquery.BigQueryOptions;

BigQuery bigquery = BigQueryOptions.defaultInstance().service();
```

For other authentication options, see the
[Authentication](https://github.com/GoogleCloudPlatform/gcloud-java#authentication) page.

#### Creating a dataset
With BigQuery you can create datasets. A dataset is a grouping mechanism that holds zero or more
tables. Add the following import at the top of your file:

```java
import com.google.gcloud.bigquery.DatasetInfo;
```
Then, to create the dataset, use the following code:

```java
// Create a dataset
String datasetId = "my_dataset_id";
bigquery.create(DatasetInfo.builder(datasetId).build());
```

#### Creating a table
With BigQuery you can create different types of tables: normal tables with an associated schema,
external tables backed by data stored on Google Cloud Storage and view tables that are created from
a BigQuery SQL query. In this code snippet we show how to create a normal table with only one string
field. Add the following imports at the top of your file:

```java
import com.google.gcloud.bigquery.Field;
import com.google.gcloud.bigquery.Schema;
import com.google.gcloud.bigquery.TableId;
import com.google.gcloud.bigquery.BaseTableInfo;
import com.google.gcloud.bigquery.TableInfo;
```
Then add the following code to create the table:

```java
TableId tableId = TableId.of(datasetId, "my_table_id");
// Table field definition
Field stringField = Field.builder("StringField", Field.Type.string())
.mode(Field.Mode.NULLABLE)
.build();
// Table schema definition
Schema schema = Schema.of(stringField);
// Create a table
BaseTableInfo createdTableInfo = bigquery.create(TableInfo.of(tableId, schema));
```

#### Loading data into a table
BigQuery provides several ways to load data into a table: streaming rows or loading data from a
Google Cloud Storage file. In this code snippet we show how to stream rows into a table.
Add the following imports at the top of your file:

```java
import com.google.gcloud.bigquery.InsertAllRequest;
import com.google.gcloud.bigquery.InsertAllResponse;

import java.util.HashMap;
import java.util.Map;
```
Then add the following code to insert data:

<!-- TODO(mziccard): add code snippet -->
```java
Map<String, Object> firstRow = new HashMap<>();
Map<String, Object> secondRow = new HashMap<>();
firstRow.put("StringField", "value1");
secondRow.put("StringField", "value2");
// Create an insert request
InsertAllRequest insertRequest = InsertAllRequest.builder(tableId)
.addRow(firstRow)
.addRow(secondRow)
.build();
// Insert rows
InsertAllResponse insertResponse = bigquery.insertAll(insertRequest);
// Check if errors occurred
if (insertResponse.hasErrors()) {
System.out.println("Errors occurred while inserting rows");
}
```

#### Querying data
BigQuery enables querying data by running queries and waiting for the result. Queries can be run
directly or through a Query Job. In this code snippet we show how to run a query directly and wait
for the result. Add the following imports at the top of your file:

```java
import com.google.gcloud.bigquery.FieldValue;
import com.google.gcloud.bigquery.QueryRequest;
import com.google.gcloud.bigquery.QueryResponse;

import java.util.Iterator;
import java.util.List;
```
Then add the following code to run the query and wait for the result:

```java
// Create a query request
QueryRequest queryRequest = QueryRequest.builder("SELECT * FROM my_dataset_id.my_table_id")
.maxWaitTime(60000L)
.maxResults(1000L)
.build();
// Request query to be executed and wait for results
QueryResponse queryResponse = bigquery.query(queryRequest);
while (!queryResponse.jobComplete()) {
Thread.sleep(1000);
queryResponse = bigquery.getQueryResults(queryResponse.jobId());
}
// Read rows
Iterator<List<FieldValue>> rowIterator = queryResponse.result().iterateAll();
System.out.println("Table rows:");
while (rowIterator.hasNext()) {
System.out.println(rowIterator.next());
}
```
#### Complete source code

Here we put together all the code shown above into one program. This program assumes that you are
running on Compute Engine or from your own desktop. To run this example on App Engine, simply move
the code from the main method to your application's servlet class and change the print statements to
display on your webpage.

```java
import com.google.gcloud.bigquery.BaseTableInfo;
import com.google.gcloud.bigquery.BigQuery;
import com.google.gcloud.bigquery.BigQueryOptions;
import com.google.gcloud.bigquery.DatasetInfo;
import com.google.gcloud.bigquery.Field;
import com.google.gcloud.bigquery.FieldValue;
import com.google.gcloud.bigquery.InsertAllRequest;
import com.google.gcloud.bigquery.InsertAllResponse;
import com.google.gcloud.bigquery.QueryRequest;
import com.google.gcloud.bigquery.QueryResponse;
import com.google.gcloud.bigquery.Schema;
import com.google.gcloud.bigquery.TableId;
import com.google.gcloud.bigquery.TableInfo;

import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

public class GcloudBigQueryExample {

public static void main(String[] args) throws InterruptedException {

// Create a service instance
BigQuery bigquery = BigQueryOptions.defaultInstance().service();

// Create a dataset
String datasetId = "my_dataset_id";
bigquery.create(DatasetInfo.builder(datasetId).build());

TableId tableId = TableId.of(datasetId, "my_table_id");
// Table field definition
Field stringField = Field.builder("StringField", Field.Type.string())
.mode(Field.Mode.NULLABLE)
.build();
// Table schema definition
Schema schema = Schema.of(stringField);
// Create a table
BaseTableInfo createdTableInfo = bigquery.create(TableInfo.of(tableId, schema));

// Define rows to insert
Map<String, Object> firstRow = new HashMap<>();
Map<String, Object> secondRow = new HashMap<>();
firstRow.put("StringField", "value1");
secondRow.put("StringField", "value2");
// Create an insert request
InsertAllRequest insertRequest = InsertAllRequest.builder(tableId)
.addRow(firstRow)
.addRow(secondRow)
.build();
// Insert rows
InsertAllResponse insertResponse = bigquery.insertAll(insertRequest);
// Check if errors occurred
if (insertResponse.hasErrors()) {
System.out.println("Errors occurred while inserting rows");
}

// Create a query request
QueryRequest queryRequest = QueryRequest.builder("SELECT * FROM my_dataset_id.my_table_id")
.maxWaitTime(60000L)
.maxResults(1000L)
.build();
// Request query to be executed and wait for results
QueryResponse queryResponse = bigquery.query(queryRequest);
while (!queryResponse.jobComplete()) {
Thread.sleep(1000);
queryResponse = bigquery.getQueryResults(queryResponse.jobId());
}
// Read rows
Iterator<List<FieldValue>> rowIterator = queryResponse.result().iterateAll();
System.out.println("Table rows:");
while (rowIterator.hasNext()) {
System.out.println(rowIterator.next());
}
}
}
```

Java Versions
-------------
Expand All @@ -53,7 +283,9 @@ Java 7 or above is required for using this client.
Testing
-------

<!-- TODO(mziccard): add this in once the RemoteGCBQMHelper class is functional -->
This library has tools to help make tests for code using Cloud BigQuery.

See [TESTING] to read more about testing.

Versioning
----------
Expand Down

0 comments on commit bf6a3fe

Please sign in to comment.