The [Cassandra / Astra DB] online store provides support for materializing feature values into an Apache Cassandra / Astra DB database for online features.
- The whole project is contained within a Cassandra keyspace
- Each feature view is mapped one-to-one to a specific Cassandra table
- This implementation inherits all strengths of Cassandra such as high availability, fault-tolerance, and data distribution
In order to use this online store, you'll need to run pip install 'feast[cassandra]'. You can then get started with the command feast init REPO_NAME -t cassandra.
{% code title="feature_store.yaml" %}
project: my_feature_repo
registry: data/registry.db
provider: local
online_store:
type: cassandra
hosts:
- 192.168.1.1
- 192.168.1.2
- 192.168.1.3
keyspace: KeyspaceName
port: 9042 # optional
username: user # optional
password: secret # optional
protocol_version: 5 # optional
load_balancing: # optional
local_dc: 'datacenter1' # optional
load_balancing_policy: 'TokenAwarePolicy(DCAwareRoundRobinPolicy)' # optional
read_concurrency: 100 # optional
write_concurrency: 100 # optional{% endcode %}
{% code title="feature_store.yaml" %}
project: my_feature_repo
registry: data/registry.db
provider: local
online_store:
type: cassandra
secure_bundle_path: /path/to/secure/bundle.zip
keyspace: KeyspaceName
username: Client_ID
password: Client_Secret
protocol_version: 4 # optional
load_balancing: # optional
local_dc: 'eu-central-1' # optional
load_balancing_policy: 'TokenAwarePolicy(DCAwareRoundRobinPolicy)' # optional
read_concurrency: 100 # optional
write_concurrency: 100 # optional{% endcode %}
The full set of configuration options is available in CassandraOnlineStoreConfig.
For a full explanation of configuration options please look at file
sdk/python/feast/infra/online_stores/contrib/cassandra_online_store/README.md.
Storage specifications can be found at docs/specs/online_store_format.md.
The set of functionality supported by online stores is described in detail here. Below is a matrix indicating which functionality is supported by the Cassandra online store.
| Cassandra | |
|---|---|
| write feature values to the online store | yes |
| read feature values from the online store | yes |
| update infrastructure (e.g. tables) in the online store | yes |
| teardown infrastructure (e.g. tables) in the online store | yes |
| generate a plan of infrastructure changes | yes |
| support for on-demand transforms | yes |
| readable by Python SDK | yes |
| readable by Java | no |
| readable by Go | no |
| support for entityless feature views | yes |
| support for concurrent writing to the same key | no |
| support for ttl (time to live) at retrieval | no |
| support for deleting expired data | no |
| collocated by feature view | yes |
| collocated by feature service | no |
| collocated by entity key | no |
To compare this set of functionality against other online stores, please see the full functionality matrix.