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Consuming Data

You can find the list of supported assets here. The current Pragma proxy addresses are:

NetworkAddressExplorer
Starknet Mainnet0x0346c57f094d641ad94e43468628d8 e9c574dcb2803ec372576ccc60a40be2c4Starkscan Voyager
Starknet Alpha-Goerli0x446812bac98c08190dee8967180f4e 3cdcd1db9373ca269904acb17f67f7093Starkscan Voyager
Starknet Alpha-Goerli 20xc28f8752abb9ed18f65fed730b8faa 69bdf6128bb730411efd916284701938Starkscan Voyager

Sample Code​

If you are just trying to get started with our price feeds, see this self-contained code snippet here. If you'd like to use more advanced oracle functions please see the further information below. You can find a full sample data feed consumer contract here and the full Oracle interface specification is available here.

%lang starknet

from starkware.cairo.common.math_cmp import is_le
from starkware.cairo.common.pow import pow

from oracle.IPragmaOracle import IPragmaOracle, PragmaAggregationModes

const PRAGMA_ORACLE_ADDRESS = 0x446812bac98c08190dee8967180f4e3cdcd1db9373ca269904acb17f67f7093;
const KEY = 19514442401534788; // str_to_felt("ETH/USD")

@view
func check_eth_usd_threshold{syscall_ptr: felt\*, range_check_ptr}(threshold: felt) -> (
is_above_threshold: felt
) {
    alloc_locals;

    let (eth_price, decimals, timestamp, num_sources_aggregated) = IPragmaOracle.get_spot(PRAGMA_ORACLE_ADDRESS, KEY, PragmaAggregationModes.MEDIAN);
    let (multiplier) = pow(10, decimals);

    let shifted_threshold = threshold * multiplier;
    let is_above_threshold = is_le(shifted_threshold, eth_price);
    return (is_above_threshold,);
}

Technical Specification​

Function: get_spot_median​

This is the the simplest function that will aggregate all data into a median for a given spot pair ID.

Inputs​

  • pair_id: uppercased utf8-encoded string

Returns​

  • price: aggregation result of all entries for the given key based on the robust median algorithm. Multiplied by 10**decimals
  • decimals: number of places that value has been shifted to allow for greater accuracy (fixed point)
  • last_updated_timestamp: timestamp of the most recent entry aggregated
  • num_sources_aggregated: number of sources aggregated in the final answer. Use this to check if one of the sources you requested was not available, or if there are enough data reports for you to rely on the answer

Function: get_spot​

Similar to get_spot_median except it allows for an additional parameter to specify a custom aggregated logic (e.g. volume-weighted average (VWAP), mean and more).

Inputs​

  • pair_id: uppercased utf8-encoded string
  • aggregation_mode: aggregation mode to use for combining the many data sources available in Pragma. Use constants defined in Pragma. Option must currently be set to MEDIAN. Additional options VWAP, EXPONENTIAL_DECAY and MEAN are coming soon.

Returns​

  • price: aggregation result of all entries for the given key based on the robust median algorithm. Multiplied by 10**decimals
  • decimals: number of places that value has been shifted to allow for greater accuracy (fixed point)
  • last_updated_timestamp: timestamp of the most recent entry aggregated
  • num_sources_aggregated: number of sources aggregated in the final answer. Use this to check if one of the sources you requested was not available, or if there are enough data reports for you to rely on the answer

Function: get_spot_median_multi​

Similar to get_spot_median except it allows for getting multiple spot prices in one call.

Inputs​

  • pair_ids_len: number of pair IDs being requested
  • pair_ids: pointer to the first uppercased utf8-encoded string in the array of pair IDs

Returns​

  • prices_response_len: number of responses returned
  • prices_response: pointer to the first response, where each response is of type PragmaPricesResponse which consists of (price, decimals, last_updated_timestamp, num_sources_aggregated) with the same interpretation as on a single get_spot_median call (see above)

Function: get_spot_with_USD_hop​

This function enables you to rebase the price, i.e. use a different base currency. For instance, if you want the price of BTC/ETH, you can combine the BTC/USD and ETH/USD price data to derive that.

Inputs​

  • base_currency_id: uppercase utf8-encoded string for the base currency (e.g. BTC)
  • quote_currency_id: uppercase utf8-encoded string for the base currency (e.g. ETH)
  • aggregation_mode: aggregation mode to use for combining the many data sources available in Pragma. Use constants defined in Pragma. Option must currently be set to MEDIAN. Additional options TWAP, EXPONENTIAL_DECAY and MEAN are coming soon.

Returns​

  • price: aggregation result of all entries for the given key (using the algorithm specified by the aggregation_mode parameter). Multiplied by 10**decimals
  • decimals: number of places that value has been shifted to allow for greater accuracy (fixed point)
  • last_updated_timestamp: timestamp of the most recent entry aggregated
  • num_sources_aggregated: number of sources aggregated in the final answer. Use this to check if one of the sources you requested was not available, or if there are enough data reports for you to rely on the answer

Function: get_spot_with_hops​

This function enables you to get the price of one currency in terms of another, by specifying the path from one the quote to the base currency. For instance, if you want the price of ETH/EUR, you can combine the ETH/USD, BTC/USD and BTC/EUR price data to derive that.

Inputs​

  • currency_ids_len: number of currency ids in the hops
  • currency_ids: pointer to the first element in the list of currency IDs, where each currency ID is the utf8-encoded string for that currency (e.g. ETH)
  • aggregation_mode: aggregation mode to use for combining the many data sources available in Pragma. Use constants defined in Pragma. Option must currently be set to MEDIAN. Additional options TWAP, EXPONENTIAL_DECAY and MEAN are coming soon.

Returns​

  • price: aggregation result of all entries for the given key (using the algorithm specified by the aggregation_mode parameter). Multiplied by 10**decimals
  • decimals: number of places that value has been shifted to allow for greater accuracy (fixed point)
  • last_updated_timestamp: timestamp of the most recent entry aggregated
  • num_sources_aggregated: number of sources aggregated in the final answer. Use this to check if one of the sources you requested was not available, or if there are enough data reports for you to rely on the answer

Function: get_spot_for_sources​

This function enables you to get the price of one currency in terms of another, by specifying the path from one the quote to the base currency. For instance, if you want the price of ETH/EUR, you can combine the ETH/USD, BTC/USD and BTC/EUR price data to derive that.

Inputs​

  • pair_id: uppercased utf8-encoded string
  • aggregation_mode: aggregation mode to use for combining the many data sources available in Pragma. Use constants defined in Pragma. Option must currently be set to MEDIAN. Additional options TWAP, EXPONENTIAL_DECAY and MEAN are coming soon.
  • sources_len: number of sources to aggregate
  • sources: pointer to the first source in the list of sources, where each source is a utf8-encoded string (e.g. "gemini")

Returns​

  • price: aggregation result of all entries for the given key (using the algorithm specified by the aggregation_mode parameter). Multiplied by 10**decimals
  • decimals: number of places that value has been shifted to allow for greater accuracy (fixed point)
  • last_updated_timestamp: timestamp of the most recent entry aggregated
  • num_sources_aggregated: number of sources aggregated in the final answer. Use this to check if one of the sources you requested was not available, or if there are enough data reports for you to rely on the answer

Function: get_futures​

This function enables you to get the price of one currency in terms of another, by specifying the path from one the quote to the base currency. For instance, if you want the price of ETH/EUR, you can combine the ETH/USD, BTC/USD and BTC/EUR price data to derive that.

Inputs​

  • pair_id: uppercased utf8-encoded string
  • expiry_timestamp: timestamp of the expiry of the future (UTC)
  • aggregation_mode: aggregation mode to use for combining the many data sources available in Pragma. Use constants defined in Pragma. Option must currently be set to MEDIAN. Additional options TWAP, EXPONENTIAL_DECAY and MEAN are coming soon.
  • sources_len: number of sources to aggregate
  • sources: pointer to the first source in the list of sources, where each source is a utf8-encoded string (e.g. "gemini")

Returns​

  • price: aggregation result of all entries for the given key (using the algorithm specified by the aggregation_mode parameter). Multiplied by 10**decimals
  • decimals: number of places that value has been shifted to allow for greater accuracy (fixed point)
  • last_updated_timestamp: timestamp of the most recent entry aggregated
  • num_sources_aggregated: number of sources aggregated in the final answer. Use this to check if one of the sources you requested was not available, or if there are enough data reports for you to rely on the answer

Function: get_spot_entry​

This function enables you to get the most recent raw data point for a specific spot asset and source.

Inputs​

  • pair_id: uppercased utf8-encoded string
  • source: uppercased utf8-encoded data source, e.g. str_to_felt("GEMINI")=78362974965321

Returns​

  • entry: entry of type SpotEntry, i.e. a struct with members base_entry, which in turn has a timestamp, source and publisher, and additional members pair_id, price and volume.

Function: get_spot_entries​

This function enables you to get the multiple raw data points for a specific spot asset and all sources.

Inputs​

  • pair_id: uppercased utf8-encoded string

Returns​

  • entries_len: the number of entries in the list returned
  • entries: pointer to the first entry, where each entry of type SpotEntry, i.e. a struct with members base_entry, which in turn has a timestamp, source and publisher, and additional members pair_id, price and volume.

Function: get_spot_entries_for_sources​

This function enables you to get the most recent raw data point for a specific spot asset and a list of sources.

Inputs​

  • pair_id: uppercased utf8-encoded string
  • sources_len: number of sources to request for sources: pointer to the first source, where each source is a uppercased utf8-encoded data source, e.g. str_to_felt("GEMINI")=78362974965321

Returns​

  • entries_len: the number of entries in the list returned
  • entries: pointer to the first entry, where each entry of type SpotEntry, i.e. a struct with members base_entry, which in turn has a timestamp, source and publisher, and additional members pair_id, price and volume.

Function: get_future_entry​

This function enables you to get the most recent raw data point for a specific future asset and source.

Inputs​

  • pair_id: uppercased utf8-encoded string
  • expiry_timestamp: timestamp of the expiry of the future
  • source: uppercased utf8-encoded data source, e.g. str_to_felt("GEMINI")=78362974965321

Returns​

  • entry: entry of type FutureEntry, i.e. a struct with members base_entry, which in turn has a timestamp, source and publisher, and additional members pair_id, expiry_timestamp and price.

Function: get_future_entries​

This function enables you to get the multiple raw data points for a specific future asset and all sources.

Inputs​

  • pair_id: uppercased utf8-encoded string
  • expiry_timestamp: timestamp of the expiry of the future

Returns​

  • entries_len: the number of entries in the list returned
  • entries: pointer to the first entry, where each entry of type FutureEntry, i.e. a struct with members base_entry, which in turn has a timestamp, source and publisher, additional members pair_id, expiry_timestamp and price.

Function: get_future_entries_for_sources​

This function enables you to get the most recent raw data point for a specific future asset and a list of sources.

Inputs​

  • pair_id: uppercased utf8-encoded string
  • expiry_timestamp: timestamp of the expiry of the future
  • sources_len: number of sources to request for
  • sources: pointer to the first source, where each source is a uppercased utf8-encoded data source, e.g. str_to_felt("GEMINI")=78362974965321

Returns​

  • entries_len: the number of entries in the list returned
  • entries: pointer to the first entry, where each entry of type FutureEntry, i.e. a struct with members base_entry, which in turn has a timestamp, source and publisher, additional members pair_id, expiry_timestamp and price.