# CIIMS web service message exchange proxy

A thin HTTP proxy that translates JSON POST requests into SOAP/XML calls to a CIIMS
ExchangeService backend. Designed for airport operational message exchange (AODB/FLOP).

## API

### POST /send

Send a message to CIIMS.

Request body (JSON):
```json
{
    "url":     "http://domain.tld",   // optional, overrides CIIMS_SERVER
    "user":    "ciims username",      // required
    "pass":    "ciims password",      // required
    "event":   "route event id",      // required
    "priority": 0,                    // optional, defaults to 0
    "val":     false,                 // optional, defaults to false
    "msg":     "ciims xml body"       // required
}
```

### POST /receive

Receive messages from CIIMS.

Request body (JSON):
```json
{
    "url":   "http://domain.tld",   // optional, overrides CIIMS_SERVER
    "user":  "ciims username",      // required
    "pass":  "ciims password",      // required
    "count": 3                      // required, 1-1000
}
```

### GET /ping

Health check — returns `{"message": "pong"}`.

## Configuration

| Environment Variable | Description | Default |
|---|---|---|
| `CIIMS_SERVER` | Base URL of the default CIIMS ExchangeService | (required) |
| `CIIMS_ALLOWED_SERVERS` | Comma-separated extra CIIMS base URLs allowed for request `url` overrides | empty |
| `PROXY_LISTEN` | Bind address for the proxy HTTP server | `:9090` |
| `CIIMS_TIMEOUT` | Outbound request timeout in seconds | `240` |

## Security Considerations

- **Authentication:** This proxy does not authenticate callers. Deploy behind a firewall or
  add a reverse-proxy layer (nginx, envoy) with API key / basic auth.
- **TLS:** Use a TLS-terminating reverse proxy in production. The proxy itself serves plain
  HTTP and transmits CIIMS credentials with every request.
- **Input limits:** Request bodies are limited to 1 MB, CIIMS responses are limited to 64 MiB, and the `count` parameter on `/receive`
  is capped at 1000.
- **URL overrides:** Per-request `url` values are accepted only when they match `CIIMS_SERVER` or an entry in `CIIMS_ALLOWED_SERVERS` after normalization.
- **Credentials:** CIIMS usernames and passwords are XML-escaped before being embedded in
  SOAP envelopes. They are not logged.

## Build

```bash
go build -o ciimsproxy ./cmd/main/
```

## Example

```bash
# Start the proxy
CIIMS_SERVER=http://192.168.1.100:8080 ./ciimsproxy

# Send a message
curl -X POST http://localhost:9090/send \
  -H 'Content-Type: application/json' \
  -d '{"user":"FIMS","pass":"FIMS","event":"FLOP-CHDT","msg":"<MSG/>"}'

# Receive messages
curl -X POST http://localhost:9090/receive \
  -H 'Content-Type: application/json' \
  -d '{"user":"FIMS","pass":"FIMS","count":5}'
```