gae-flexible-helloworld

Google App Engine Flexible - Hello World

App Engine Flexible compat runtime has full access to AppEngine Services and API's.

This app provides:

1. A web interface that uses Cloud Bigtable to track the number of visits from an opaque version of your Google account.
2. A simple REST interface that can read and write arbitrary data to a Cloud Bigtable table using GET, POST, and DELETE verbs.

SECURITY WARNING – This app will read / write the two tables you create (gae-hello and from-json) The app provides NO ADDITIONAL SECURITY PROTECTIONS. We suggest that instances should only be available while testing and that test data be used.

Table of Contents

1. Requirements
2. Project Setup
3. Running Locally
4. Deploying the AppEngine Flexible Runtime
5. AppEngine Debugging Hints
6. Using Bigtable-Hello
7. Using-JSON

Requirements

1. Latest version of gcloud
2. Update with gcloud components update
3. gcloud init (if you haven't already)
4. gcloud components update alpha beta app-engine-java
5. Java 1.8
6. Maven

Project Setup

1. Follow the instructions for Creating a Google Developers Console project and client ID

2. Use Cloud Console to enable billing.

3. Select APIs & Auth > APIs

4. Enable the APIs: Cloud Bigtable API and the Cloud Bigtable Admin API
   (You may need to search for the API.)

5. Select Storage > Bigtable > Create Cluster.

   Create a new Cluster -- You will need both the Zone and the Cluster ID

6. Follow the instructions to launch HBase shell Quickstart

7. Create the table (tableName, Column Family)

create 'gae-hello', 'visits'
create 'from-json', 'cf1', 'cf2', 'cf3', 'cf4'
exit

Running Locally

1. Build and run the Project

   mvn clean gcloud:run -Pmac -Dbigtable.projectID=myProject -Dbigtable.clusterID=myCluster -Dbigtable.zone=myZone

   NOTE - The -Pmac is REQUIRED for running on a Macintosh, -Pwindows is used for running on Windows, and the option is not required for Linux.

   NOTE - These parameters are required every time you run the app, if you plan on running it a lot, you may wish to set these values in the pom.xml directly.

2. Access the page by going to localhost:8080 from your browser, it should ask you to login, and count that for you.

Deploying the AppEngine Runtime

1. Deploy the application

   mvn clean gcloud:deploy -Dbigtable.projectID=myProject -Dbigtable.clusterID=myCluster -Dbigtable.zone=myZone

   NOTE - These parameters are required every time you run the app, if you plan on running it a lot, you may wish to set these values in the pom.xml directly.

2. Go to the new default module which will be displayed in results from the deploy. It will look like: https://PROJECTID.appspot.com you can go to that URL to test.

AppEngine Debugging Hints

The first thing to do, if you'd like to debug is use the servlet.log() methods, they seem to work when other loggers don't. Then take control of your GAE instance:

1. Find your instance gcloud preview app modules list

2. Connect to an instance with ssh

3. Find the Container

4. Either show the container log sudo docker logs <containerID> or enter the container sudo docker exec -it <containerID> /bin/bash

Using the example

1. With your browser, go to localhost:8080 in your browser. (Local) Or to https://<projectID>.appspot.com

2. Sign-in with Google. Your visit should increment the counter.

Using JSON

1. Entities (rows) can be accessed using https://<projectID>.appspot.com/json/rowkey

• GET - Will wrap up everything as JSON
• POST - Will convert the JSON to ColumnFamily : Qualifier and write the data
• DELETE - Will remove the row.

1. The URL should be either localhost:8080, docker:8080, or https://<projectID>.appspot.com

2. curl -H "Content-Type: application/json" -X POST -d '{"username":"red","id":535}' http://localhost:8080/json/blueword

3. curl -X GET http://localhost:8080/json/blueword

4. curl -H "Content-Type: application/json" -X DELETE http://localhost:8080/json/blueword

You will note that none of these examples use Column Family specifiers. It defaults to using cf1, if you wish to use the other column families specify <columnFamily>:<column> where columnFamily is one of cf1, cf2, cf3, or cf4 that you created earlier.