currency: added in-memory service;

pkg/currency/in_memory_service.go

@@ -0,0 +1,49 @@
+package currency
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/justtrackio/gosoline/pkg/cfg"
+	"github.com/justtrackio/gosoline/pkg/clock"
+	"github.com/justtrackio/gosoline/pkg/http"
+	"github.com/justtrackio/gosoline/pkg/kvstore"
+	"github.com/justtrackio/gosoline/pkg/log"
+)
+
+// NewInMemoryService creates a currency Service which never updates and reads all currency values in the constructor.
+// It can be useful when you need to run a tool or similar and don't want to store the currency data somewhere or have
+// a complicated module setup.
+func NewInMemoryService(ctx context.Context, config cfg.Config, logger log.Logger) (Service, error) {
+	logger = logger.WithChannel("in-memory-currency-service")
+
+	store, err := kvstore.NewInMemoryKvStore[float64](ctx, config, logger, &kvstore.Settings{
+		Ttl: time.Hour * 24 * 365, // data never expires or updates
+		InMemorySettings: kvstore.InMemorySettings{
+			MaxSize: 1_000_000_000,
+		},
+	})
+	if err != nil {
+		return nil, fmt.Errorf(": %w", err)
+	}
+
+	httpClient, err := http.ProvideHttpClient(ctx, config, logger, "currencyUpdater")
+	if err != nil {
+		return nil, fmt.Errorf("can not create http client: %w", err)
+	}
+
+	updater := NewUpdaterWithInterfaces(logger, store, httpClient, clock.Provider)
+
+	err = updater.EnsureRecentExchangeRates(ctx)
+	if err != nil {
+		return nil, fmt.Errorf("failed to fetch recent exchange rates: %w", err)
+	}
+
+	err = updater.EnsureHistoricalExchangeRates(ctx)
+	if err != nil {
+		return nil, fmt.Errorf("failed to fetch historical exchange rates: %w", err)
+	}
+
+	return NewWithInterfaces(store, clock.Provider), nil
+}