# Cloud Monitoring Sample

Simple command-line program to demonstrate connecting to the Google
Monitoring API to retrieve API data.

This also includes an example of how to create a cusom metric and
write a TimeSeries value to it.

## Prerequisites to run locally:

    * [Maven 3](https://maven.apache.org)
    * [GCloud CLI](https://cloud.google.com/sdk/gcloud/)
    * Create a Cloud project

# Set Up Your Local Dev Environment

Create local credentials by running the following command and following the oauth2 flow:

    gcloud beta auth application-default login

To run:

    * `mvn clean install`
    * `./list_resources_example.sh <YOUR-PROJECT-ID>`
    * `./run_custom_metrics.sh <YOUR-PROJECT-ID>`

## Running on GCE, GAE, or other environments

On Google App Engine, the credentials should be found automatically.

On Google Compute Engine, the credentials should be found automatically, but require that
you create the instance with the correct scopes.

    gcloud compute instances create --scopes="https://www.googleapis.com/auth/cloud-platform,https://www.googleapis.com/auth/compute,https://www.googleapis.com/auth/compute.readonly" test-instance

If you did not create the instance with the right scopes, you can still upload a JSON service
account and set `GOOGLE_APPLICATION_CREDENTIALS` as described below.

## Using a Service Account

In non-Google Cloud environments, GCE instances created without the correct scopes, or local
workstations if the `gcloud beta auth application-default login` command fails, use a Service
Account by doing the following:

* Go to API Manager -> Credentials
* Click 'New Credentials', and create a Service Account or [click  here](https://console.cloud.google
.com/project/_/apiui/credential/serviceaccount)
 Download the JSON for this service account, and set the `GOOGLE_APPLICATION_CREDENTIALS`
 environment variable to point to the file containing the JSON credentials.


    export GOOGLE_APPLICATION_CREDENTIALS=~/Downloads/<project-id>-0123456789abcdef.json

## Run Tests

The tests emulate what the scripts accomplish, so there isn't a reason why they
need to be run if the examples work.  However, if you'd like to run them, change
`TEST_PROJECT_ID` in [`ListResourcesTest`](src/test/java/ListResourcesTest.java)
to the appropriate project ID that matches the Service Account pointed to by
`GOOGLE_APPLICATION_CREDENTIALS`, then run:

    mvn test -DskipTests=false
