BLNK Go Proxy

Lightweight proxy that adapts JavaScript/TypeScript clients to BLNK Core Banking to avoid large-integer issues. It lets clients send precise_amount as a string and converts it to an integer before forwarding the request to the core, preventing errors like Do not know how to serialize a BigInt or values being turned into exponential notation.

What It Does

• Listens on ProxyPort and forwards everything to the host/port set in config/config.go.
• If the body is JSON and contains precise_amount as a string, it converts it to an integer and logs the conversion.
• If precise_amount is missing, already numeric, or cannot be converted, the request is forwarded unchanged (invalid cases are logged as warnings).

Requirements

• Go >= 1.24 (see go.mod).
• Network connectivity to the configured BLNK instance.

Configuration

Edit config/config.go to point to the core:

• TargetHost: BLNK host or IP.
• TargetPort: BLNK port.
• ProxyPort: port where the proxy listens (defaults to 5000).

Run

go run .
# or
go build -o blnkGoProxy && ./blnkGoProxy

Example from a JS/TS client (sending the amount as a string):

curl -X POST http://localhost:5000/transactions \
  -H "Content-Type: application/json" \
  -d '{"precise_amount":"123456789012345678", "account_id":"abc123"}'

The proxy converts precise_amount to an integer and forwards the request to BLNK at TargetHost:TargetPort. The core’s response is returned unchanged to the client.

Notes and Limitations

• Only processes application/json bodies and the top-level precise_amount field.
• Conversion uses Go int; ensure values fit the target platform limits.
• Conversion errors do not stop the request: the original body is forwarded and a warning is printed to stdout.