Front-End Web & Mobile

Geo Library for Amazon DynamoDB – Part 2: GeoDataManagerConfiguration

In order to use Geo Library for Amazon DynamoDB, you need to go through some setup steps. GeoDataManagerConfiguration represents the mandatory and optional configurations, and in this blog post, I’ll show you how to use GeoDataManagerConfiguration to customize the behavior of Geo Library.

Instantiating GeoDataManager

GeoDataManager is the main class you interact with when using Geo Library. In order to instantiate GeoDataManager, you need to pass an instance of GeoDataManagerConfiguration:

AWSCredentials credentials = new BasicAWSCredentials(YOUR_ACCESS_KEY, YOUR_SECRET_KEY);
AmazonDynamoDBClient ddb = new AmazonDynamoDBClient(credentials);
Region usWest2 = Region.getRegion(Regions.US_WEST_2);
ddb.setRegion(usWest2);

GeoDataManagerConfiguration config = new GeoDataManagerConfiguration(ddb, "geo-test");
GeoDataManager geoIndexManager = new GeoDataManager(config);

In the above example, you are telling GeoDataManager to use a DynamoDB table named geo-test in the US West (Oregon) region.

NOTE: It is important to correctly set your region on AmazonDynamoDBClient to where your table is. For the full list of regions, refer to Regions and Endpoints.

GeoDataManagerConfiguration

GeoDataManagerConfiguration allows you to configure many aspects of GeoDataManager:

Configurable Attribute Required / Optional Default
AmazonDynamoDBClient used to access the DynamoDB table Required N/A
Amazon DynamoDB table name Required N/A
Attribute name of the hash key Optional hashKey
Attribute name of the range key Optional rangeKey
Attribute name of the Geohash Optional geohash
Attribute name of the Geo Json Optional geoJson
Index name on the Geohash attribute Optional geohash-index
Length of hash key Optional 6
ExecutorService used to control threading Optional Thread pool size of 10

Example

For instance, when you instantiate GeoDataManager with the above code snippet, the library will work with the following DynamoDB table:

Table name: geo-test

hashKey (Hash key) rangeKey (Range key) geohash (Indexed: index name is geohash-index) geoJson …and your additional attributes …
… … … … … …

If you want to customize it and use a different table called Schools,

Table name: Schools

schoolHashKey (Hash key) schoolId (Range key) schoolGeohash (Indexed: index name is school-geohash-index) schoolGeoJson …and your additional attributes …
… … … … … …

you can instantiate GeoDataManager as follows:

AWSCredentials credentials = new BasicAWSCredentials(YOUR_ACCESS_KEY, YOUR_SECRET_KEY);
AmazonDynamoDBClient ddb = new AmazonDynamoDBClient(credentials);
Region usWest2 = Region.getRegion(Regions.US_WEST_2);
ddb.setRegion(usWest2);

GeoDataManagerConfiguration config = new GeoDataManagerConfiguration(ddb, "Schools")
        .withHashKeyAttributeName("schoolHashKey")
        .withRangeKeyAttributeName("schoolId")
        .withGeohashAttributeName("schoolGeohash")
        .withGeoJsonAttributeName("schoolGeoJson")
        .withGeohashIndexName("school-geohash-index");
GeoDataManager geoIndexManager = new GeoDataManager(config);

As always, please leave a comment below if you have questions.

Further Reading