# README
Postgres reader
Postgres reader 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_READER_LOG_LEVEL | Service log level | info |
| SMQ_POSTGRES_READER_HTTP_HOST | Service HTTP host | localhost |
| SMQ_POSTGRES_READER_HTTP_PORT | Service HTTP port | 9009 |
| SMQ_POSTGRES_READER_HTTP_SERVER_CERT | Service HTTP server cert | "" |
| SMQ_POSTGRES_READER_HTTP_SERVER_KEY | Service HTTP server key | "" |
| SMQ_POSTGRES_HOST | Postgres DB host | localhost |
| 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_CLIENTS_AUTH_GRPC_URL | Clients service Auth gRPC URL | localhost:7000 |
| SMQ_CLIENTS_AUTH_GRPC_TIMEOUT | Clients service Auth gRPC timeout in seconds | 1s |
| SMQ_CLIENTS_AUTH_GRPC_CLIENT_TLS | Clients service Auth gRPC TLS mode flag | false |
| SMQ_CLIENTS_AUTH_GRPC_CA_CERTS | Clients service Auth gRPC CA certificates | "" |
| SMQ_AUTH_GRPC_URL | Auth service gRPC URL | localhost:7001 |
| SMQ_AUTH_GRPC_TIMEOUT | Auth service gRPC request timeout in seconds | 1s |
| SMQ_AUTH_GRPC_CLIENT_TLS | Auth service gRPC TLS mode flag | false |
| SMQ_AUTH_GRPC_CA_CERTS | Auth service gRPC CA certificates | "" |
| SMQ_JAEGER_URL | Jaeger server URL | http://jaeger:4318/v1/traces |
| SMQ_SEND_TELEMETRY | Send telemetry to supermq call home server | true |
| SMQ_POSTGRES_READER_INSTANCE_ID | Postgres reader instance ID |
Deployment
The service itself is distributed as Docker container. Check the postgres-reader 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_READER_LOG_LEVEL=[Service log level] \
SMQ_POSTGRES_READER_HTTP_HOST=[Service HTTP host] \
SMQ_POSTGRES_READER_HTTP_PORT=[Service HTTP port] \
SMQ_POSTGRES_READER_HTTP_SERVER_CERT=[Service HTTPS server certificate path] \
SMQ_POSTGRES_READER_HTTP_SERVER_KEY=[Service HTTPS server key path] \
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_CLIENTS_AUTH_GRPC_URL=[Clients service Auth GRPC URL] \
SMQ_CLIENTS_AUTH_GRPC_TIMEOUT=[Clients service Auth gRPC request timeout in seconds] \
SMQ_CLIENTS_AUTH_GRPC_CLIENT_TLS=[Clients service Auth gRPC TLS mode flag] \
SMQ_CLIENTS_AUTH_GRPC_CA_CERTS=[Clients service Auth gRPC CA certificates] \
SMQ_AUTH_GRPC_URL=[Auth service gRPC URL] \
SMQ_AUTH_GRPC_TIMEOUT=[Auth service gRPC request timeout in seconds] \
SMQ_AUTH_GRPC_CLIENT_TLS=[Auth service gRPC TLS mode flag] \
SMQ_AUTH_GRPC_CA_CERTS=[Auth service gRPC CA certificates] \
SMQ_JAEGER_URL=[Jaeger server URL] \
SMQ_SEND_TELEMETRY=[Send telemetry to supermq call home server] \
SMQ_POSTGRES_READER_INSTANCE_ID=[Postgres reader instance ID] \
$GOBIN/supermq-postgres-reader
Usage
Starting service will start consuming normalized messages in SenML format.
Comparator Usage Guide:
| Comparator | Usage | Example |
|---|---|---|
| eq | Return values that are equal to the query | eq["active"] -> "active" |
| ge | Return values that are substrings of the query | ge["tiv"] -> "active" and "tiv" |
| gt | Return values that are substrings of the query and not equal to the query | gt["tiv"] -> "active" |
| le | Return values that are superstrings of the query | le["active"] -> "tiv" |
| lt | Return values that are superstrings of the query and not equal to the query | lt["active"] -> "active" and "tiv" |
Official docs can be found here.