# README
Postgres writer
Postgres writer provides message repository implementation for Postgres.
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 |
|---|---|---|
| SMQ_POSTGRES_WRITER_LOG_LEVEL | Service log level | info |
| SMQ_POSTGRES_WRITER_CONFIG_PATH | Config file path with Message broker subjects list, payload type and content-type | /config.toml |
| SMQ_POSTGRES_WRITER_HTTP_HOST | Service HTTP host | localhost |
| SMQ_POSTGRES_WRITER_HTTP_PORT | Service HTTP port | 9010 |
| SMQ_POSTGRES_WRITER_HTTP_SERVER_CERT | Service HTTP server certificate path | "" |
| SMQ_POSTGRES_WRITER_HTTP_SERVER_KEY | Service HTTP server key | "" |
| SMQ_POSTGRES_HOST | Postgres DB host | postgres |
| SMQ_POSTGRES_PORT | Postgres DB port | 5432 |
| SMQ_POSTGRES_USER | Postgres user | supermq |
| SMQ_POSTGRES_PASS | Postgres password | supermq |
| SMQ_POSTGRES_NAME | Postgres database name | messages |
| SMQ_POSTGRES_SSL_MODE | Postgres SSL mode | disabled |
| SMQ_POSTGRES_SSL_CERT | Postgres SSL certificate path | "" |
| SMQ_POSTGRES_SSL_KEY | Postgres SSL key | "" |
| SMQ_POSTGRES_SSL_ROOT_CERT | Postgres SSL root certificate path | "" |
| SMQ_MESSAGE_BROKER_URL | Message broker instance URL | nats://localhost:4222 |
| SMQ_JAEGER_URL | Jaeger server URL | http://jaeger:4318/v1/traces |
| SMQ_SEND_TELEMETRY | Send telemetry to supermq call home server | true |
| SMQ_POSTGRES_WRITER_INSTANCE_ID | Service instance ID | "" |
Deployment
The service itself is distributed as Docker container. Check the postgres-writer service section in docker-compose file 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/absmach/supermq
cd supermq
# compile the postgres writer
make postgres-writer
# copy binary to bin
make install
# Set the environment variables and run the service
SMQ_POSTGRES_WRITER_LOG_LEVEL=[Service log level] \
SMQ_POSTGRES_WRITER_CONFIG_PATH=[Config file path with Message broker subjects list, payload type and content-type] \
SMQ_POSTGRES_WRITER_HTTP_HOST=[Service HTTP host] \
SMQ_POSTGRES_WRITER_HTTP_PORT=[Service HTTP port] \
SMQ_POSTGRES_WRITER_HTTP_SERVER_CERT=[Service HTTP server cert] \
SMQ_POSTGRES_WRITER_HTTP_SERVER_KEY=[Service HTTP server key] \
SMQ_POSTGRES_HOST=[Postgres host] \
SMQ_POSTGRES_PORT=[Postgres port] \
SMQ_POSTGRES_USER=[Postgres user] \
SMQ_POSTGRES_PASS=[Postgres password] \
SMQ_POSTGRES_NAME=[Postgres database name] \
SMQ_POSTGRES_SSL_MODE=[Postgres SSL mode] \
SMQ_POSTGRES_SSL_CERT=[Postgres SSL cert] \
SMQ_POSTGRES_SSL_KEY=[Postgres SSL key] \
SMQ_POSTGRES_SSL_ROOT_CERT=[Postgres SSL Root cert] \
SMQ_MESSAGE_BROKER_URL=[Message broker instance URL] \
SMQ_JAEGER_URL=[Jaeger server URL] \
SMQ_SEND_TELEMETRY=[Send telemetry to supermq call home server] \
SMQ_POSTGRES_WRITER_INSTANCE_ID=[Service instance ID] \
$GOBIN/supermq-postgres-writer
Usage
Starting service will start consuming normalized messages in SenML format.