migrate from ExchangeRate.Host to Frankfurter

mtotschnig · Sep 27, 2023 · 1824c8f · 1824c8f
1 parent 58295f4
commit 1824c8f
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Showing 7 changed files with 101 additions and 60 deletions.
diff --git a/myExpenses/src/androidTest/java/org/totschnig/myexpenses/test/room/ExchangeRateDaoTest.kt b/myExpenses/src/androidTest/java/org/totschnig/myexpenses/test/room/ExchangeRateDaoTest.kt
@@ -58,17 +58,17 @@ class ExchangeRateDaoTest {
     @Throws(InterruptedException::class)
     fun getProductsWhenNoProductInserted() {
         runBlocking {
-            assertNull(exchangeRateDao.getRate("EUR", "USD", localDate, "EXCHANGE_RATE_HOST"))
+            assertNull(exchangeRateDao.getRate("EUR", "USD", localDate, "FRANKFURTER"))
         }
     }
 
     @Test
     @Throws(InterruptedException::class)
     fun getProductsAfterInserted() {
-        val exchangeRate = ExchangeRate("EUR", "USD", localDate, 1.444, "EXCHANGE_RATE_HOST")
+        val exchangeRate = ExchangeRate("EUR", "USD", localDate, 1.444, "FRANKFURTER")
         runBlocking {
             exchangeRateDao.insert(exchangeRate)
-            assertEquals(1.444, exchangeRateDao.getRate("EUR", "USD", localDate, "EXCHANGE_RATE_HOST"))
+            assertEquals(1.444, exchangeRateDao.getRate("EUR", "USD", localDate, "FRANKFURTER"))
         }
     }
 }
diff --git a/myExpenses/src/main/java/org/totschnig/myexpenses/di/NetworkModule.kt b/myExpenses/src/main/java/org/totschnig/myexpenses/di/NetworkModule.kt
@@ -17,8 +17,8 @@ import org.totschnig.myexpenses.MyApplication
 import org.totschnig.myexpenses.preference.PrefHandler
 import org.totschnig.myexpenses.provider.ExchangeRateRepository
 import org.totschnig.myexpenses.retrofit.CoinApi
-import org.totschnig.myexpenses.retrofit.ExchangeRateHost
 import org.totschnig.myexpenses.retrofit.ExchangeRateService
+import org.totschnig.myexpenses.retrofit.Frankfurter
 import org.totschnig.myexpenses.retrofit.OpenExchangeRates
 import org.totschnig.myexpenses.retrofit.RoadmapService
 import org.totschnig.myexpenses.room.ExchangeRateDatabase.Companion.getDatabase
@@ -112,16 +112,16 @@ open class NetworkModule {
         @JvmStatic
         @Provides
         @Singleton
-        fun provideExchangeRateHost(
+        fun provideFrankfurter(
             builder: OkHttpClient.Builder,
             converterFactory: GsonConverterFactory
-        ): ExchangeRateHost {
+        ): Frankfurter {
             val retrofit = Retrofit.Builder()
-                .baseUrl("https://api.exchangerate.host/")
+                .baseUrl("https://api.frankfurter.app/")
                 .addConverterFactory(converterFactory)
                 .client(builder.build())
                 .build()
-            return retrofit.create(ExchangeRateHost::class.java)
+            return retrofit.create(Frankfurter::class.java)
         }
 
         @JvmStatic
@@ -161,7 +161,7 @@ open class NetworkModule {
         @Provides
         @Singleton
         fun provideExchangeRateService(
-            api1: ExchangeRateHost,
+            api1: Frankfurter,
             api2: OpenExchangeRates,
             api3: CoinApi
         ) = ExchangeRateService(api1, api2, api3)

diff --git a/myExpenses/src/main/java/org/totschnig/myexpenses/retrofit/ExchangeRateHost.kt b/myExpenses/src/main/java/org/totschnig/myexpenses/retrofit/ExchangeRateHost.kt
diff --git a/myExpenses/src/main/java/org/totschnig/myexpenses/retrofit/ExchangeRateService.kt b/myExpenses/src/main/java/org/totschnig/myexpenses/retrofit/ExchangeRateService.kt
@@ -8,6 +8,7 @@ import org.totschnig.myexpenses.preference.PrefKey
 import retrofit2.HttpException
 import retrofit2.await
 import java.io.IOException
+import java.lang.UnsupportedOperationException
 import java.time.Instant
 import java.time.LocalDate
 import java.time.ZoneId
@@ -23,30 +24,67 @@ sealed class ExchangeRateSource(val id: String, val host: String) {
 
     companion object {
 
-        val values = arrayOf(ExchangeRateHost, OpenExchangeRates, CoinApi)
+        val values = arrayOf(Frankfurter, OpenExchangeRates, CoinApi)
 
         fun preferredSource(prefHandler: PrefHandler) =
             preferredSource(prefHandler.getString(PrefKey.EXCHANGE_RATE_PROVIDER, null))
 
         fun preferredSource(preferenceValue: String?) =
-            values.firstOrNull { it.id == preferenceValue } ?: ExchangeRateHost
+            values.firstOrNull { it.id == preferenceValue } ?: Frankfurter
     }
 
-    object ExchangeRateHost : ExchangeRateSource("EXCHANGE_RATE_HOST", "exchangerate.host") {
-        override fun extractError(body: ResponseBody) = body.string().takeIf { it.isNotEmpty() }
+    data object Frankfurter : ExchangeRateSource("FRANKFURTER", "api.frankfurter.app") {
+
+        val SUPPORTED_CURRENCIES = arrayOf(
+            "AUD",
+            "BGN",
+            "BRL",
+            "CAD",
+            "CHF",
+            "CNY",
+            "CZK",
+            "DKK",
+            "EUR",
+            "GBP",
+            "HKD",
+            "HUF",
+            "IDR",
+            "ILS",
+            "INR",
+            "ISK",
+            "JPY",
+            "KRW",
+            "MXN",
+            "MYR",
+            "NOK",
+            "NZD",
+            "PHP",
+            "PLN",
+            "RON",
+            "SEK",
+            "SGD",
+            "THB",
+            "TRY",
+            "USD",
+            "ZAR"
+        )
+
+        override fun extractError(body: ResponseBody): String =
+            JSONObject(body.string()).getString("message")
+
     }
 
     sealed class SourceWithApiKey(
         val prefKey: PrefKey,
         host: String,
         id: String
-    ): ExchangeRateSource(id, host) {
+    ) : ExchangeRateSource(id, host) {
         fun requireApiKey(prefHandler: PrefHandler): String =
             prefHandler.getString(prefKey)
                 ?: throw MissingApiKeyException(this)
     }
 
-    object OpenExchangeRates : SourceWithApiKey(
+    data object OpenExchangeRates : SourceWithApiKey(
         prefKey = PrefKey.OPEN_EXCHANGE_RATES_APP_ID,
         host = "openexchangerates.com",
         id = "OPENEXCHANGERATES"
@@ -55,7 +93,7 @@ sealed class ExchangeRateSource(val id: String, val host: String) {
             JSONObject(body.string()).getString("description")
     }
 
-    object CoinApi : SourceWithApiKey(
+    data object CoinApi : SourceWithApiKey(
         prefKey = PrefKey.COIN_API_API_KEY,
         host = "coinapi.io",
         id = "COIN_API"
@@ -69,7 +107,7 @@ class MissingApiKeyException(val source: ExchangeRateSource.SourceWithApiKey) :
     java.lang.IllegalStateException("${source.prefKey.name} not configured")
 
 class ExchangeRateService(
-    private val exchangeRateHost: @NotNull ExchangeRateHost,
+    private val frankfurter: @NotNull Frankfurter,
     private val openExchangeRates: @NotNull OpenExchangeRates,
     private val coinApi: @NotNull CoinApi
 ) {
@@ -81,18 +119,19 @@ class ExchangeRateService(
         base: String
     ): Pair<LocalDate, Double> = try {
         when (source) {
-            ExchangeRateSource.ExchangeRateHost -> {
-                val today = LocalDate.now()
-                if (date < today) {
-                    val result: ExchangeRateHost.TimeSeriesResult = exchangeRateHost.getTimeSeries(date, date, symbol, base).await()
-                    result.rates[date]?.get(symbol)?.let {
-                        date to it
-                    } ?: throw IOException("Unable to retrieve data")
-                } else {
-                    val result = exchangeRateHost.getLatest(symbol, base).await()
+            ExchangeRateSource.Frankfurter -> {
+                if (symbol in ExchangeRateSource.Frankfurter.SUPPORTED_CURRENCIES && base in ExchangeRateSource.Frankfurter.SUPPORTED_CURRENCIES) {
+                    val today = LocalDate.now()
+                    val (dateOfResult, result) = if (date < today) {
+                        date to frankfurter.getHistorical(date, symbol, base).await()
+                    } else {
+                        today to frankfurter.getLatest(symbol, base).await()
+                    }
                     result.rates[symbol]?.let {
-                        today to it
+                        dateOfResult to it
                     } ?: throw IOException("Unable to retrieve data")
+                } else {
+                    throw UnsupportedOperationException()
                 }
             }
 
@@ -118,7 +157,12 @@ class ExchangeRateService(
                 if (date < today) {
                     val call = coinApi.getHistory(base, symbol, date, date.plusDays(1), apiKey)
                     val result = call.await().first()
-                    date to arrayOf(result.rate_close, result.rate_high, result.rate_low, result.rate_close).average()
+                    date to arrayOf(
+                        result.rate_close,
+                        result.rate_high,
+                        result.rate_low,
+                        result.rate_close
+                    ).average()
                 } else {
                     val call = coinApi.getExchangeRate(base, symbol, apiKey)
                     val result = call.await()

diff --git a/myExpenses/src/main/java/org/totschnig/myexpenses/retrofit/Frankfurter.kt b/myExpenses/src/main/java/org/totschnig/myexpenses/retrofit/Frankfurter.kt
@@ -0,0 +1,26 @@
+package org.totschnig.myexpenses.retrofit
+
+import androidx.annotation.Keep
+import retrofit2.Call
+import retrofit2.http.GET
+import retrofit2.http.Path
+import retrofit2.http.Query
+import java.time.LocalDate
+
+interface Frankfurter {
+    @GET("latest")
+    fun getLatest(
+        @Query("to") symbol: String,
+        @Query("from") base: String
+    ): Call<Result>
+
+    @GET("{date}")
+    fun getHistorical(
+        @Path("date") date: LocalDate,
+        @Query("to") symbol: String,
+        @Query("from") base: String
+    ): Call<Result>
+
+    @Keep
+    data class Result(val rates: Map<String, Double>)
+}
diff --git a/myExpenses/src/main/res/xml/preferences_exchange_rate.xml b/myExpenses/src/main/res/xml/preferences_exchange_rate.xml
@@ -19,7 +19,7 @@
     android:title="@string/pref_category_exchange_rates">
     <org.totschnig.myexpenses.preference.HeaderPreference />
     <ListPreference
-        android:defaultValue="EXCHANGE_RATE_HOST"
+        android:defaultValue="FRANKFURTER"
         android:key="@string/pref_exchange_rate_provider_key"
         android:summary="@string/pref_exchange_rate_provider_summary"
         android:title="@string/pref_exchange_rate_provider_title" />

diff --git a/myExpenses/src/test/java/org/totschnig/myexpenses/retrofit/ExchangeRateServiceTest.kt b/myExpenses/src/test/java/org/totschnig/myexpenses/retrofit/ExchangeRateServiceTest.kt
@@ -34,9 +34,9 @@ class ExchangeRateServiceTest {
     }
 
     @Test
-    fun exchangeRateHostIsAlive() {
+    fun frankfurterIsAlive() {
         runBlocking {
-            val rate = service.getRate(ExchangeRateSource.ExchangeRateHost, null, date, "USD", "EUR")
+            val rate = service.getRate(ExchangeRateSource.Frankfurter, null, date, "USD", "EUR")
             Truth.assertThat(rate.first).isEqualTo(date)
             println(rate.second.toString())
         }