cryptoprice/README.md

Retrieve cryptocurrencies current (buy, sell or spot) prices

A simple implementation of the prices Coinbase Public API.

Examples (TL;DR)

import net.thauvin.erik.crypto.CryptoPrice.Companion.buyPrice
import net.thauvin.erik.crypto.CryptoPrice.Companion.sellPrice
import net.thauvin.erik.crypto.CryptoPrice.Companion.spotPrice

val btc = spotPrice("BTC") // Bitcoin
println(btc.amount)

val eth = sellPrice("ETH", "EUR") // Ethereum in Euro
println(eth.amount)

val eth = buyPrice("LTC", "GBP") // Litecoin in Pound sterling
println(eth.amount)

• View bld or Gradle Examples.

bld

To use with bld, include the following dependency in your build file:

repositories = List.of(MAVEN_CENTRAL);

scope(compile)
    .include(dependency("net.thauvin.erik:cryptoprice:1.0.2"));

Be sure to use the bld Kotlin extension in your project.

Gradle, Maven, etc.

To use with Gradle, include the following dependency in your build file:

repositories {
    mavenCentral()
    maven { url = uri("https://oss.sonatype.org/content/repositories/snapshots") } // only needed for SNAPSHOT
}

dependencies {
    implementation("net.thauvin.erik:cryptoprice:1.0.2")
}

Instructions for using with Maven, Ivy, etc. can be found on Maven Central.

Prices

The spotPrice, buyPrice and sellPrice functions define the following parameters:

spotPrice(
    base: String, // Required 
    currency: String = "USD",
    date: LocalDate? = null
)

buyPrice(
    base: String, // Required 
    currency: String = "USD"
)

sellPrice(
    base: String, // Required 
    currency: String = "USD"
)

Parameters	Description
base	The cryptocurrency ticker symbol (BTC, ETH, LTC, etc.)
currency	The fiat currency ISO 4217 code. (USD, GBP, EUR, etc.)
date	The LocalDate for historical price data.

A CryptoPrice object is returned defined as follows:

CryptoPrice(val base: String, val currency: String, val amount: BigDecimal)

The parameter names match the Coinbase API.

Format

To display the amount as a formatted currency, use the toCurrency function:

val euro = CryptoPrice("BTC", "EUR", 23456.78.toBigDecimal())
println(euro.toCurrency()) // €23,456.78

val krone = CryptoPrice("BTC", "DKK", 123456.78.toBigDecimal())
println(krone.toCurrency(Locale.Builder().setLanguage("da").setRegion("DK").build())) // 123.456,78 kr.

JSON

To convert a CryptoPrice object back to JSON, use the toJson function:

val price = CryptoPrice("BTC", "USD", 34567.89.toBigDecimal())
println(price.toJson())

output:

{"data":{"base":"BTC","currency":"USD","amount":"34567.89"}}

The data object matches the Coinbase API. To specify a different (or no) key, use:

println(price.toJson("bitcoin"))
println(price.toJson("")) // or price.toString()

output:

{"bitcoin":{"base":"BTC","currency":"USD","amount":"34567.89"}}
{"base":"BTC","currency":"USD","amount":"34567.89"}

Similarly, to create a CryptoPrice object from JSON, use the toPrice function:

val btc = """{"data":{"base":"BTC","currency":"USD","amount":"34567.89"}}""".toPrice()
val eth = """{"ether":{"base":"ETH","currency":"USD","amount":"2345.67"}}""".toPrice("ether")

Extending

A generic apiCall() function is available to access other data API endpoints. For example to retrieve the exchange rates:

apiCall(listOf("exchange-rates"), mapOf("currency" to "usd"))

will return something like:

{"data":{"currency":"BTC","rates":{"AED":"36.73","AFN":"589.50","...":"..."}}}

See the examples for more details.

Contributing

If you want to contribute to this project, all you have to do is clone the GitHub repository:

git clone git@github.com:ethauvin/cryptoprice.git

Then use bld to build:

cd cryptoprice
./bld compile

The project has an IntelliJ IDEA project structure. You can just open it after all the dependencies were downloaded and peruse the code.