sim-bacen-spb

SPB (Sistema de Pagamentos Brasileiros) simulator implementing Brazilian financial message protocols.

IBM MQ Queue Configuration

The simulator implements explicit queue separation for IBM MQ message routing:

Request Queue (IBMMQ_QL_REQ_NAME)

• Purpose: Inbound financial institution requests
• Consumers: MQ worker (continuous polling)
• Publishers: Test endpoints (/api/ingest/str*), IF via external MQ
• Typical value: QL.REQ.00000000.99999999.01
• Environment variable: IBMMQ_QL_REQ_NAME

The MQ worker polls this queue continuously and processes:

• STR (Structured Transfer Request) messages from financial institutions
• Test/injection messages from development endpoints

Response Queue (IBMMQ_QL_RSP_NAME)

• Purpose: Outbound responses and autonomous BACEN messages
• Consumers: External systems monitoring BACEN responses
• Publishers: Response handlers, SLB ingest (/api/ingest/slb*), producer
• Typical value: QL.RSP.00000000.99999999.01
• Environment variable: IBMMQ_QL_RSP_NAME

The response queue is where:

• Reply messages (R1, R2, R3 responses to STR requests) are published
• Autonomous SLB messages (SLB0001, SLB0002, SLB0006, SLB0007) are published
• External systems consume BACEN responses

Configuration at Startup

Queue names are resolved from environment variables once at component startup, not on each message:

# Backend component initialization
IBMMQ_QL_REQ_NAME=QL.REQ.00000000.99999999.01 \
IBMMQ_QL_RSP_NAME=QL.RSP.00000000.99999999.01 \
java -jar backend.jar

All subsequent polling and sending uses the initialized values. Changing env vars after startup has no effect on running components.

Graceful Degradation

If a queue doesn't exist (MQRC 2085):

• Producer: Returns false, logs warning with queue name and timestamp. No exception thrown.
• Consumer: Logs warning, returns empty message list, continues polling at interval.
• Service: Remains operational. Fix the queue and resume normal operation.

Code Architecture

• Consumer (infrastructure/mq/consumer.clj): Accepts request-queue-name as parameter
• Producer (infrastructure/mq/producer.clj): Accepts queue-name as parameter
• MQ Worker (components/mq_worker.clj): Resolves both queue names via config.reader at startup
• Config Reader (config/reader.clj): Defines mq-request-queue-name and mq-response-queue-name functions
• SLB Ingest (controllers/slb/ingest.clj): Uses mq-response-queue-name for autonomous messages