# PriceAuthority Object

We rely on PriceAuthority oracles. A PriceAuthority gives reliable quotes for prices. The quotes might be based on broad surveys of prices across the ecosystem, or might come directly from an AMM (Automatic Market Maker). A PriceAuthority can either give a quote for the current price across any pair of currencies it knows about, or can immediately return a Promise resolved when a condition is true. For example, a price crossing some threshold, or at a particular time. It can also provide a price feed that updates with every price change.

# E(PriceAuthority).getQuoteIssuer(brandIn, brandOut)

  • brandIn: Brand
  • brandOut: Brand
  • Returns: Issuer | Promise<Issuer>

Gets the ERTP Issuer of PriceQuotes for a given brandIn/brandOut pair.

const quoteIssuer = await E(PriceAuthority).getQuoteIssuer(
    collateralKit.brand,
    loanKit.brand
  );

# E(PriceAuthority).getTimerService(brandIn, brandOut)

  • brandIn: Brand
  • brandOut: Brand
  • Returns: TimerService | Promise<TimerService>

Gets the timer used in PriceQuotes for a given brandIn/brandOut pair.

const myTimer = E(PriceAuthority).getTimerService(collateral.brand, loanKit.brand);

# E(PriceAuthority).makeQuoteNotifier(amountIn, brandOut)

Be notified of the latest PriceQuotes for a given amountIn. The issuing rate may be very different between PriceAuthorities.

const myNotifier = E(PriceAuthority).makeQuoteNotifier(quatloos100, usdBrand);

# E(PriceAuthority).quoteGiven(amountIn, brandOut)

Gets a quote on-demand corresponding to amountIn.

const quote = await E(PriceAuthority).quoteGiven(moola500, quatloosBrand);

# E(PriceAuthority).quoteWanted(brandIn, amountOut)

Gets a quote on-demand corresponding to amountOut.

const quote = await E(PriceAuthority).quoteWanted(quatloosBrand, moola500);

# E(PriceAuthority).quoteAtTime(deadline, amountIn, brandOut)

Resolves after deadline passes on the PriceAuthority’s timerService with the PriceQuote of amountIn at that time. Note that deadline's value is a BigInt.

const priceQuoteOnThisAtTime = E(PriceAuthority).quoteAtTime(7n, quatloosAmount34, usdBrand);

# E(PriceAuthority).quoteWhenGT(amountIn, amountOutLimit)

Resolves when a PriceQuote of amountIn exceeds amountOutLimit.

const quote = E(PriceAuthority).quoteWhenGT(
    AmountMath.make(brands.In, 29n),
    AmountMath.make(brands.Out, 974n)
  );

# E(PriceAuthority).quoteWhenGTE(amountIn, amountOutLimit)

Resolves when a PriceQuote of amountIn reaches or exceeds amountOutLimit.

const quote = E(PriceAuthority).quoteWhenGTE(
    AmountMath.make(brands.In, 29n),
    AmountMath.make(brands.Out, 974n)
  );

# E(PriceAuthority).quoteWhenLT(amountIn, amountOutLimit)

Resolves when a PriceQuote of amountIn drops below amountOutLimit.

const quote = E(PriceAuthority).quoteWhenLT(
    AmountMath.make(brands.In, 29n),
    AmountMath.make(brands.Out, 974n)
  );

# E(PriceAuthority).quoteWhenLTE(amountIn, amountOutLimit)

Resolves when a PriceQuote of amountIn reaches or drops below amountOutLimit.

const quote = E(PriceAuthority).quoteWhenLTE(
    AmountMath.make(brands.In, 29n),
    AmountMath.make(brands.Out, 974n)
  );

# E(PriceAuthority).mutableQuoteWhenGT(amountIn, amountOutLimit)

Resolves when a PriceQuote of amountIn exceeds amountOutLimit.

const quote = E(PriceAuthority).mutableQuoteWhenGT(
    AmountMath.make(brands.In, 29n),
    AmountMath.make(brands.Out, 974n)
  );

# E(PriceAuthority).mutableQuoteWhenGTE(amountIn, amountOutLimit)

Resolves when a PriceQuote of amountIn reaches or exceeds amountOutLimit.

const quote = E(PriceAuthority).mutableQuoteWhenGTE(
    AmountMath.make(brands.In, 29n),
    AmountMath.make(brands.Out, 974n)
  );

# E(PriceAuthority).mutableQuoteWhenLT(amountIn, amountOutLimit)

Resolves when a PriceQuote of amountIn drops below amountOutLimit.

const quote = E(PriceAuthority).mutableQuoteWhenLT(
    AmountMath.make(brands.In, 29n),
    AmountMath.make(brands.Out, 974n)
  );

# E(PriceAuthority).mutableQuoteWhenLTE(amountIn, amountOutLimit)

Resolves when a PriceQuote of amountIn reaches or drops below amountOutLimit.

const quote = E(PriceAuthority).mutableQuoteWhenLTE(
    AmountMath.make(brands.In, 29n),
    AmountMath.make(brands.Out, 974n)
  );