# Google Cloud Spanner Sample

This sample demonstrates how to use [Google Cloud Spanner][spanner-docs]
from [Google App Engine standard environment][ae-docs].

[spanner-docs]: https://cloud.google.com/spanner/docs/
[ae-docs]: https://cloud.google.com/appengine/docs/java/


## Setup
- Install the [Google Cloud SDK](https://cloud.google.com/sdk/) and run:
```
   gcloud init
```
If this is your first time creating an App engine application:
```
   gcloud app create
```
- [Create a Spanner instance](https://cloud.google.com/spanner/docs/quickstart-console#create_an_instance).

- Update `SPANNER_INSTANCE` value in `[appengine-web.xml](src/main/webapp/WEB-INF/appengine-web.xml).

## Endpoints
- `/spanner` : will run sample operations against the spanner instance in order. Individual tasks can be run
using the `task` query parameter. See [SpannerTasks](src/main/java/com/example/appengine/spanner/SpannerTasks.java)
for supported set of tasks.
Note : by default all the spanner example operations run in order, this operation may take a while to return.

## Running locally
- Authorize the local application:
```
   gcloud auth application-default login
```
You may also [create and use service account credentials](https://cloud.google.com/docs/authentication/getting-started#creating_the_service_account).

- App Engine Maven plugins do not work correctly for this sample for local testing.
  Here is the [tracking issue](https://github.com/GoogleCloudPlatform/google-cloud-java/issues/2155).
  As a workaround to run locally, this sample uses the [Maven Jetty plugin](http://www.eclipse.org/jetty/documentation/9.4.x/jetty-maven-plugin.html).
```
   mvn -DSPANNER_INSTANCE=my-spanner-instance jetty:run
```

To see the results of the local application, open
[http://localhost:8080/spanner](http://localhost:8080/spanner) in a web browser.
Note : by default all the spanner example operations run in order, this operation may take a while to show results.

## Deploying

    $ mvn clean appengine:deploy

To see the results of the deployed sample application, open
`https://spanner-dot-PROJECTID.appspot.com/spanner` in a web browser.
Note : by default all the spanner example operations run in order, this operation may take a while to show results.