11.1. Installing GeoMesa Cassandra

11.1.1. Installing Cassandra

The first step to getting started with Cassandra and GeoMesa is to install Cassandra itself. You can find good directions for downloading and installing Cassandra online. For example, see Cassandra’s official “Getting Started” documentation here: https://cassandra.apache.org/doc/latest/getting_started/index.html .

Once you have Cassandra installed, the next step is to prepare your Cassandra installation to integrate with GeoMesa. First, create a key space within Cassandra. The easiest way to do this with cqlsh, which should have been installed as part of your Cassandra installation. Start cqlsh, then type:

CREATE KEYSPACE mykeyspace WITH REPLICATION = {'class': 'SimpleStrategy', 'replication_factor' : 3};

This creates a key space called “mykeyspace”. This is a top-level name space within Cassandra and it will provide a place for GeoMesa to put all of its data, including data for spatial features and associated metadata.

Next, you’ll need to set the CASSANDRA_LIB environment variable. GeoMesa uses this variable to find the Cassandra jars. These jars should be in the lib directory of your Cassandra installation. To set the variable add the following line to your .profile or .bashrc file:

export CASSANDRA_LIB=/path/to/cassandra/lib

Finally, make sure you know a contact point for your Cassandra instance. If you are just trying things locally, and using the default Cassandra settings, the contact point would be 127.0.0.1:9042. You can check and configure the port you are using using the native_transport_port in the Cassandra configuration file (located at conf/cassandra.yaml in your Cassandra installation directory).

11.1.2. Installing the GeoMesa Cassandra Data Store

After you’ve successfully installed and configured Cassandra, you can move on to installing the GeoMesa Cassandra distribution. Start by choosing or creating a directory where you want to put it. Then cd into that directory and type:

wget https://repo.locationtech.org/content/repositories/geomesa-releases/org/locationtech/geomesa/geomesa-cassandra-dist_2.11/$VERSION/geomesa-cassandra-dist_2.11-$VERSION-bin.tar.gz
tar xvf geomesa-cassandra-dist_2.11-$VERSION-bin.tar.gz

Note

Make sure to replace $VERSION with the version of the distribution that you want to use, i.e. “1.3.0”.

You can browse available versions at https://repo.locationtech.org/content/repositories/geomesa-releases/org/locationtech/geomesa/geomesa-cassandra-dist_2.11/.

The directory that you just extracted is the GEOMESA_CASSANDRA_HOME. It includes all the files that we’ll need to use GeoMesa with Cassandra.

11.1.3. Installing GeoMesa Cassandra in GeoServer

The GeoMesa Cassandra distribution includes a GeoServer plugin for including Cassandra data stores in GeoServer. The plugin files are in the dist/gs-plugins/geomesa-cassandra-gs-plugin_2.11-$VERSION-install.tar.gz archive within the GeoMesa Cassandra distribution directory. To install the plugins, extract the archive and copy the contents to the WEB-INF/lib directory of your GeoServer installation. You will also need to copy the JARs from the lib directory of your Cassandra installation into the GeoServer WEB-INF/lib directory.

Restart GeoServer after the JARs are installed.