Config: Refactor version packages (#1887)

* Config: Move config versions to separate pacakges

* Config: Move version tests to blackbox texts

* Config: Protect registerVersion from overflow

* Config: Protect against version already registered

config/versions/v1/v1.go

@@ -0,0 +1,53 @@
+package v1
+
+import (
+	"context"
+
+	"github.com/buger/jsonparser"
+	v0 "github.com/thrasher-corp/gocryptotrader/config/versions/v0"
+	"github.com/thrasher-corp/gocryptotrader/encoding/json"
+)
+
+// Version is an ExchangeVersion to upgrade currency pair format for exchanges
+type Version struct{}
+
+// Exchanges returns all exchanges: "*"
+func (*Version) Exchanges() []string { return []string{"*"} }
+
+// UpgradeExchange will upgrade currency pair format
+func (*Version) UpgradeExchange(_ context.Context, e []byte) ([]byte, error) {
+	if _, d, _, err := jsonparser.Get(e, "currencyPairs"); err == nil && d == jsonparser.Object {
+		return e, nil
+	}
+
+	d := &v0.Exchange{}
+	if err := json.Unmarshal(e, d); err != nil {
+		return e, err
+	}
+
+	p := &PairsManager{
+		UseGlobalFormat: true,
+		LastUpdated:     d.PairsLastUpdated,
+		ConfigFormat:    d.ConfigCurrencyPairFormat,
+		RequestFormat:   d.RequestCurrencyPairFormat,
+		Pairs: FullStore{
+			"spot": {
+				Available: d.AvailablePairs,
+				Enabled:   d.EnabledPairs,
+			},
+		},
+	}
+	j, err := json.Marshal(p)
+	if err != nil {
+		return e, err
+	}
+	for _, f := range []string{"pairsLastUpdated", "configCurrencyPairFormat", "requestCurrencyPairFormat", "assetTypes", "availablePairs", "enabledPairs"} {
+		e = jsonparser.Delete(e, f)
+	}
+	return jsonparser.Set(e, j, "currencyPairs")
+}
+
+// DowngradeExchange doesn't do anything for v1; There's no downgrade path since the original state is lossy and v1 was before versioning
+func (*Version) DowngradeExchange(_ context.Context, e []byte) ([]byte, error) {
+	return e, nil
+}

config/versions/v1/v1_test.go

@@ -0,0 +1,37 @@
+package v1_test
+
+import (
+	"bytes"
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	v1 "github.com/thrasher-corp/gocryptotrader/config/versions/v1"
+)
+
+func TestExchanges(t *testing.T) {
+	t.Parallel()
+	assert.Equal(t, []string{"*"}, new(v1.Version).Exchanges())
+}
+
+func TestUpgradeExchange(t *testing.T) {
+	t.Parallel()
+
+	v := &v1.Version{}
+	in := []byte(`{"name":"Wibble","pairsLastUpdated":1566798411,"assetTypes":"spot","configCurrencyPairFormat":{"uppercase":true,"delimiter":"_"},"requestCurrencyPairFormat":{"uppercase":false,"delimiter":"_","separator":"-"},"enabledPairs":"LTC_BTC","availablePairs":"LTC_BTC,ETH_BTC,BTC_USD"}`)
+	exp := []byte(`{"name":"Wibble","currencyPairs":{"bypassConfigFormatUpgrades":false,"requestFormat":{"uppercase":false,"delimiter":"_","separator":"-"},"configFormat":{"uppercase":true,"delimiter":"_"},"useGlobalFormat":true,"lastUpdated":1566798411,"pairs":{"spot":{"enabled":"LTC_BTC","available":"LTC_BTC,ETH_BTC,BTC_USD"}}}}`)
+
+	out, err := v.UpgradeExchange(context.Background(), in)
+	require.NoError(t, err)
+	require.NotEmpty(t, out)
+	assert.Equal(t, string(exp), string(out))
+}
+
+func TestDowngradeExchange(t *testing.T) {
+	t.Parallel()
+	in := []byte("just leave me alone, mkay?")
+	out, err := new(v1.Version).DowngradeExchange(context.Background(), bytes.Clone(in))
+	require.NoError(t, err)
+	assert.Equal(t, out, in)
+}