Subscriptions: Add IgnoringAssetsKey

exchanges/subscription/keys.go

@@ -87,3 +87,38 @@ func (k IgnoringPairsKey) Match(eachKey MatchableKey) bool {
 		eachSub.Levels == k.Levels &&
 		eachSub.Interval == k.Interval
 }
+
+// IgnoringAssetKey is a key type for finding subscriptions to group together for requests
+type IgnoringAssetKey struct {
+	*Subscription
+}
+
+var _ MatchableKey = IgnoringAssetKey{} // Enforce IgnoringAssetKey must implement MatchableKey
+
+// GetSubscription returns the underlying subscription
+func (k IgnoringAssetKey) GetSubscription() *Subscription {
+	return k.Subscription
+}
+
+// String implements Stringer; returns the asset and Channel name but no pairs
+func (k IgnoringAssetKey) String() string {
+	s := k.Subscription
+	if s == nil {
+		return "Uninitialised IgnoringAssetKey"
+	}
+	return fmt.Sprintf("%s %s", s.Channel, s.Pairs)
+}
+
+// Match implements MatchableKey
+func (k IgnoringAssetKey) Match(eachKey MatchableKey) bool {
+	if eachKey == nil {
+		return false
+	}
+	eachSub := eachKey.GetSubscription()
+
+	return eachSub != nil &&
+		eachSub.Channel == k.Channel &&
+		eachSub.Pairs.Equal(k.Pairs) &&
+		eachSub.Levels == k.Levels &&
+		eachSub.Interval == k.Interval
+}

exchanges/subscription/keys_test.go

@@ -110,6 +110,39 @@ func TestIgnoringPairsKeyString(t *testing.T) {
 	assert.Equal(t, "ticker spot", key.String())
 }
 
+// TestIgnoringAssetKeyMatch exercises IgnoringAssetKey.Match
+func TestIgnoringAssetKeyMatch(t *testing.T) {
+	t.Parallel()
+
+	key := &IgnoringAssetKey{&Subscription{Channel: TickerChannel, Asset: asset.Spot}}
+	try := &DummyKey{&Subscription{Channel: OrderbookChannel}, t}
+
+	require.False(t, key.Match(nil), "Match on a nil must return false")
+	require.False(t, key.Match(try), "Gate 1: Match must reject a bad Channel")
+	try.Channel = TickerChannel
+	require.True(t, key.Match(try), "Gate 1: Match must accept a good Channel")
+	key.Pairs = currency.Pairs{btcusdtPair}
+	require.False(t, key.Match(try), "Gate 2: Match must reject bad Pairs")
+	try.Pairs = currency.Pairs{btcusdtPair}
+	require.True(t, key.Match(try), "Gate 2: Match must accept a good Pairs")
+	key.Levels = 4
+	require.False(t, key.Match(try), "Gate 3: Match must reject a bad Level")
+	try.Levels = 4
+	require.True(t, key.Match(try), "Gate 3: Match must accept a good Level")
+	key.Interval = kline.FiveMin
+	require.False(t, key.Match(try), "Gate 4: Match must reject a bad Interval")
+	try.Interval = kline.FiveMin
+	require.True(t, key.Match(try), "Gate 4: Match must accept a good Interval")
+}
+
+// TestIgnoringAssetKeyString exercises IgnoringAssetKey.String
+func TestIgnoringAssetKeyString(t *testing.T) {
+	t.Parallel()
+	assert.Equal(t, "Uninitialised IgnoringAssetKey", IgnoringAssetKey{}.String())
+	key := &IgnoringAssetKey{&Subscription{Asset: asset.Spot, Channel: TickerChannel, Pairs: currency.Pairs{ethusdcPair, btcusdtPair}}}
+	assert.Equal(t, "ticker [ETHUSDC BTCUSDT]", key.String())
+}
+
 // TestGetSubscription exercises GetSubscription
 func TestGetSubscription(t *testing.T) {
 	t.Parallel()