CryptoPriceOracle

Fetches exchange rates for currency pairs (eg. XRP/USD, BTC/EUR) from various sources. Data can be stored in memory, MariaDB or PostgreSQL. For XRPL it's additionally possible to store exchange rates on-chain using an XRPL TrustSet command.

If stored in memory or a database, this service offers a REST API to fetch persisted data. API calls are protected using env.ADMINPWR and x-api-key HTTP header.

Don't trust. Verify. Run your own instance to ensure you're getting the expected data.

Wallets on-chain storage

• r3PDXzXky6gboMrwurmSCiUyhzdrFyAbfu (XRPL main)
• 2024-04-20 Deprecated rpXCfDds782Bd6eK9Hsn15RDnGMtxf752m (XRPL main)

HTTP endpoints

url	description	examples
GET /rate/:id?quote=USD	Get latest quote for currency pair	/rate/XRP?quote=USD (x-api-key required)
GET /rate/:id?quote=USD&at=YYYYMMDDTHHmmssZ	Get quote for currency pair at a point in (UTC) time	/rate/XRP?quote=USD&at=20231207T073723Z (x-api-key required)
GET /apikey	List all api keys	/apikey?pwr=env.ADMINPWR
POST /apikey	Create new api key for URL encoded form data 'name'	/apikey?pwr=env.ADMINPWR
GET /health	HTTP 200 if good or HTTP 500 with details	/health?pwr=env.ADMINPWR
GET /status	JSON status response	/status?pwr=env.ADMINPWR

Config

Exchange rate sources are defined in ./provider/definitions with one json file per base currency.

.env variable	values (<default>)	description
PORT	<3000>	HTTP port for service
TIMEOUT_SECONDS	<15>	Timeout seconds for exchange rate source timeout
LOG_INFO	<false>	True if infos should be printed to console
UNHEALTHY_AFTER	<900000>	Millis without any new exchange rates until service returns HTTP 500 at /health
UNHEALTHY_SHELL_COMMAND		Shell command to be executed if the service considers itself unhealthy
ADMINPWR		Password for administrative calls
APIKEYS		Comma separated list of additional valid api keys
FETCH_CURRENCIES	[XRP,XAH], <[]>	Comma separated list of baseCurrencies to be fetched. [] or obmitted is considered all
PUBLISH_INTERVAL	<60000>	Fetch & publish trigger interval in millis
RATELIMIT_WINDOW_MS	<60000>	API rate limit time window in millis
RATELIMIT_MAX	<60>	API rate limit max calls in time window
DB_PROVIDER	mariadb, postgres	Storage provider or null, for memory storage only
DB_HOST		Database (db) server name
DB_NAME		Database name
DB_USER		Database user
DB_PASSWORD		Database password
RATESTORE_MAXAGE_SECONDS	<5184000>, <7200>	Maximum age to keep in storage before removal (2 month for db, 2 hours for memory)
XRPL_TRUSTLINE_PUBLISH_CONFIG	'json_array'	JSON config string for XRPL on-chain storage or omitted if not used

XRPL_TRUSTLINE_PUBLISH_CONFIG

A JSON array defining how and which exchange rates should be stored on-chain.

Example

[
  {
    "publishCurrencies": [
      "XRP"
    ],
    "endpoint": "wss://s.altnet.rippletest.net:51233",
    "maxFeeDrops": 1010,
    "accountPublicKey": "rKF4sbPfJiNUQwAh4R6PuYqJRCxaBX8W76",
    "accountSecret": "s...",
    "issuerPublicKey": "r9yFdE8aASi5opAoYASYpyo9iqYF8Ly3jJ"
  },
  {
    "publishCurrencies": [
      "XAH"
    ],
    "endpoint": "wss://xahau-test.net",
    "feeProvider": "hooksFee",
    "maxFeeDrops": 1500,
    "accountPublicKey": "rHEbBTy4t5BGS7o4EmHyP6uZ9P7M53mziK",
    "accountSecret": "s...",
    "issuerPublicKey": "r32imWPz2BX199eFi12Uae3AEZYv93BBGT"
  }
]