Data APIs for Apache Cassandra

Easy to use APIs for accessing data stored in Apache Cassandra.

These APIs can be used as a standalone server using either Docker or manually running a server. They can also be embedded in existing applications using HTTP routes.

Currently, this project provides GraphQL APIs. Other API types are possible in the future.

Getting Started

Installation

docker pull datastaxlabs/cassandra-data-apis
docker run -p 8080:8080 -e DATA_API_HOSTS=<cassandra_hosts_here> datastaxlabs/cassandra-data-apis

You can also manually build the docker image and/or the server using the instructions below.

Running in the background

You can start the container in detached mode by using -d and --rm flags.

docker run --rm -d -p 8080:8080 -e DATA_API_HOSTS=<cassandra_hosts_here> datastaxlabs/cassandra-data-apis

Running on macOS or Windows for development purposes

When using Docker for Desktop, if your Cassandra instance is listening on the loopback address 127.0.0.1, you can use host.docker.internal name which resolves to the internal IP address used by the host.

docker run -p 8080:8080 -e DATA_API_HOSTS=host.docker.internal datastaxlabs/cassandra-data-apis

Using GraphQL

By default, a GraphQL endpoint is started and will generate a GraphQL schema per keyspace. You need at least one user-defined keyspace in your database to get started.

Use the GraphQL documentation for getting started.

Configuration

Configuration for Docker can be done using either environment variables, a mounted configuration file, or both.

Add additional configuration using environment variables by adding them to the docker run command.

docker run -e DATA_API_HOSTS=127.0.0.1 -e DATA_API_KEYSPACE=example ...

Using a configuration file

To use a configuration file, create a file with the following contents:

hosts:
  # Change to your cluster's hosts
  - 127.0.0.1
# keyspace: example
# username: cassandra
# password: cassandra

# See the "Settings" section for additional configuration

Then start docker with:

docker run -p 8080:8080 -v "${PWD}/<your_config_file>.yaml:/root/config.yaml" datastaxlabs/cassandra-data-apis

Settings

Name	Type	Env. Variable	Description
hosts	strings	DATA_API_HOSTS	Hosts for connecting to the database
keyspace	string	DATA_API_KEYSPACE	Only allow access to a single keyspace
excluded-keyspaces	strings	DATA_API_EXCLUDED_KEYSPACES	Keyspaces to exclude from the endpoint
username	string	DATA_API_USERNAME	Connect with database user
password	string	DATA_API_PASSWORD	Database user's password
operations	strings	DATA_API_OPERATIONS	A list of supported schema management operations. See below. (default "TableCreate, KeyspaceCreate")
request-logging	bool	DATA_API_REQUEST_LOGGING	Enable request logging
schema-update-interval	duration	DATA_API_SCHEMA_UPDATE_INTERVAL	Interval in seconds used to update the graphql schema (default 10s)
ssl-enabled	bool	DATA_API_SSL_ENABLED	Enable SSL (client-to-node encryption)?
ssl-ca-cert-path	string	DATA_API_SSL_CA_CERT_PATH	SSL CA certificate path
ssl-client-cert-path	string	DATA_API_SSL_CLIENT_CERT_PATH	SSL client certificate path
ssl-client-key-path	string	DATA_API_SSL_CLIENT_KEY_PATH	SSL client private key path
ssl-host-verification	string	DATA_API_SSL_HOST_VERIFICATION	Verify the peer certificate? It is highly insecure to disable host verification (default true)
start-graphql	bool	DATA_API_START_GRAPHQL	Start the GraphQL endpoint (default true)
graphql-path	string	DATA_API_GRAPHQL_PATH	GraphQL endpoint path (default "/graphql")
graphql-port	int	DATA_API_GRAPHQL_PORT	GraphQL endpoint port (default 8080)
graphql-schema-path	string	DATA_API_GRAPHQL_SCHEMA_PATH	GraphQL schema management path (default "/graphql-schema")

Configuration Types

The strings type expects a comma-delimited list e.g. 127.0.0.1, 127.0.0.2, 127.0.0.3 when using environment variables or a command flag, and it expects an array type when using a configuration file.

YAML:

--- 
host: 
  - "127.0.0.1"
  - "127.0.0.2"
  - "127.0.0.3"

JSON:

{
  "hosts": ["127.0.0.1", "127.0.0.2", "127.0.0.3"]
}

Schema Management Operations

Operation	Allows
TableCreate	Creation of tables
TableDrop	Removal of tables
TableAlterAdd	Add new table columns
TableAlterDrop	Remove table columns
KeyspaceCreate	Creation of keyspaces
KeyspaceDrop	Removal of keyspaces

TLS/SSL

HTTPS

The API endpoint does not currently support HTTPS natively, but it can be handled by a gateway or reverse proxy. More information about protecting the API endpoint can be found in this documentation.

Client-to-node Encryption

By default, traffic between the API endpoints and the database servers is not encrypted. To secure this traffic you will need to generate SSL certificates and enable SSL on the database servers. More information about enabling SSL (client-to-node encryption) on the database servers can be found in this documentation. After SSL is enabled on the database servers use the ssl-enabled option, along with ssl-ca-cert-path to enable secure connections. ssl-ca-cert-path is a path to the chain of certificates used to generate the database server's certificates. The certificate chain is used by API endpoints to verify the database server's certificates. The ssl-client-cert-path and ssl-client-key-path options are not required, but can be use to provide client-side certificates that are used by the database servers to authenticate and verify the API servers, this is known as mutual authentication.

Building

This section is mostly for developers. Pre-built docker image recommended.

Building the Docker Image

cd <path_to_data-apis>/cassandra-data-apis
docker build -t cassandra-data-apis .

Run locally with single node, local Cassandra cluster

cd <path_to_data-apis>/cassandra-data-apis
docker build -t cassandra-data-apis .

# On Linux (with a cluster started on the docker bridge: 172.17.0.1)
docker run -p 8080:8080 -e "DATA_API_HOSTS=172.17.0.1" cassandra-data-apis

# With a cluster bound to 0.0.0.0
docker run --network host -e "DATA_API_HOSTS=127.0.0.1" cassandra-data-apis

# On macOS (with a cluster bound to 0.0.0.0)
docker run -p 8080:8080 -e "DATA_API_HOSTS=host.docker.internal" cassandra-data-apis

These host values can also be used in the configuration file approach used in the previous section.

Build and run as a standalone webserver

If you want to run this module as a standalone webserver, use:

# Define the keyspace you want to use
# Start the webserver
go build run.exe && ./run.exe --hosts 127.0.0.1 --keyspace store

Your settings can be persisted using a configuration file:

hosts:
  - 127.0.0.1
keyspace: store
operations:
  - TableCreate
  - KeyspaceCreate
port: 8080
schema-update-interval: 30s

To start the server using a configuration file, use:

./run.exe --config <your_config_file>.yaml

Settings can also be overridden using environment variables prefixed with DATA_API_:

DATA_API_HOSTS=127.0.0.1 DATA_API_KEYSPACE=store ./run.exe --config <your_config_file>.yaml

Plugin the routes within your HTTP request router

Installation

go get github.com/datastax/cassandra-data-apis

Using the API

To add the routes to your existing HTTP request router, use:

cfg := endpoint.NewEndpointConfig("your.first.contact.point", "your.second.contact.point")
// Setup config here using your env variables
endpoint, err := cfg.NewEndpoint()
if err != nil {
	log.Fatalf("unable create new endpoint: %s", err)
}
keyspace := "store"
routes, err = endpoint.RoutesKeyspaceGraphQL("/graphql", keyspace)
// Setup routes on your http router

License

© DataStax, Inc.

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.