Mainflux.mainflux/readers/cassandra

Cassandra reader

Cassandra reader provides message repository implementation for Cassandra.

Configuration

The service is configured using the environment variables presented in the following table. Note that any unset variables will be replaced with their default values.

Variable	Description	Default
MF_CASSANDRA_READER_LOG_LEVEL	Cassandra service log level	debug
MF_CASSANDRA_READER_HTTP_HOST	Cassandra service HTTP host	localhost
MF_CASSANDRA_READER_HTTP_PORT	Cassandra service HTTP port	9003
MF_CASSANDRA_READER_HTTP_SERVER_CERT	Cassandra service HTTP server cert	""
MF_CASSANDRA_READER_HTTP_SERVER_KEY	Cassandra service HTTP server key	""
MF_CASSANDRA_CLUSTER	Cassandra cluster comma separated addresses	localhost
MF_CASSANDRA_USER	Cassandra DB username	mainflux
MF_CASSANDRA_PASS	Cassandra DB password	mainflux
MF_CASSANDRA_KEYSPACE	Cassandra keyspace name	messages
MF_CASSANDRA_PORT	Cassandra DB port	9042
MF_THINGS_AUTH_GRPC_URL	Things service Auth gRPC URL	localhost:7000
MF_THINGS_AUTH_GRPC_TIMEOUT	Things service Auth gRPC request timeout in seconds	1
MF_THINGS_AUTH_GRPC_CLIENT_TLS	Things service Auth gRPC TLS enabled	false
MF_THINGS_AUTH_GRPC_CA_CERTS	Things service Auth gRPC CA certificates	""
MF_AUTH_GRPC_URL	Users service gRPC URL	localhost:7001
MF_AUTH_GRPC_TIMEOUT	Users service gRPC request timeout in seconds	1s
MF_AUTH_GRPC_CLIENT_TLS	Users service gRPC TLS enabled	false
MF_AUTH_GRPC_CA_CERT	Users service gRPC CA certificates	""
MF_JAEGER_URL	Jaeger server URL	http://jaeger:14268/api/traces
MF_SEND_TELEMETRY	Send telemetry to mainflux call home server	true
MF_CASSANDRA_READER_INSTANCE_ID	Cassandra Reader instance ID	""

Deployment

The service itself is distributed as Docker container. Check the cassandra-reader service section in docker-compose to see how service is deployed.

To start the service, execute the following shell script:

# download the latest version of the service
git clone https://github.com/mainflux/mainflux

cd mainflux

# compile the cassandra
make cassandra-reader

# copy binary to bin
make install

# Set the environment variables and run the service
MF_CASSANDRA_READER_LOG_LEVEL=[Cassandra Service log level] \
MF_CASSANDRA_READER_HTTP_HOST=[Cassandra Service HTTP host] \
MF_CASSANDRA_READER_HTTP_PORT=[Cassandra Service HTTP port] \
MF_CASSANDRA_READER_HTTP_SERVER_CERT=[Cassandra Service HTTP server cert] \
MF_CASSANDRA_READER_HTTP_SERVER_KEY=[Cassandra Service HTTP server key] \
MF_CASSANDRA_CLUSTER=[Cassandra cluster comma separated addresses] \
MF_CASSANDRA_KEYSPACE=[Cassandra keyspace name] \
MF_CASSANDRA_USER=[Cassandra DB username] \
MF_CASSANDRA_PASS=[Cassandra DB password] \
MF_CASSANDRA_PORT=[Cassandra DB port] \
MF_THINGS_AUTH_GRPC_URL=[Things service Auth gRPC URL] \
MF_THINGS_AUTH_GRPC_TIMEOUT=[Things service Auth gRPC request timeout in seconds] \
MF_THINGS_AUTH_GRPC_CLIENT_TLS=[Things service Auth gRPC TLS enabled] \
MF_THINGS_AUTH_GRPC_CA_CERTS=[Things service Auth gRPC CA certificates] \
MF_AUTH_GRPC_URL=[Users service gRPC URL] \
MF_AUTH_GRPC_TIMEOUT=[Users service gRPC request timeout in seconds] \
MF_AUTH_GRPC_CLIENT_TLS=[Users service gRPC TLS enabled] \
MF_AUTH_GRPC_CA_CERT=[Users service gRPC CA certificates] \
MF_JAEGER_URL=[Jaeger server URL] \
MF_SEND_TELEMETRY=[Send telemetry to mainflux call home server] \
MF_CASSANDRA_READER_INSTANCE_ID=[Cassandra Reader instance ID] \
$GOBIN/mainflux-cassandra-reader

Using docker-compose

This service can be deployed using docker containers. Docker compose file is available in <project_root>/docker/addons/cassandra-reader/docker-compose.yml. In order to run all Mainflux core services, as well as mentioned optional ones, execute following command:

docker-compose -f docker/docker-compose.yml up -d
./docker/addons/cassandra-writer/init.sh
docker-compose -f docker/addons/casandra-reader/docker-compose.yml up -d

Usage

Service exposes HTTP API for fetching messages.

Note: Cassandra Reader doesn't support searching substrings from string_value, due to inefficient searching as the current data model is not suitable for this type of queries.