Bitfinex: Refactor websocket wsUpdate handling and various improvements (#1317)

* Bitfinex: Fix cancel/update order WS ack not seen

Fixes #1288

* Bitfinex: Fix ws Unsubscribe and Resubscribe

Unsubscribe needed to use the channel id.
Resubscribe needs to have the original subscription params.

* Bitfinex: Fix ws Trades Fees on te

The ws channel for authenticated Trades sends two types of update:
* te, Trade Executed
* tu, Trade Execution Update

Only the second one contains fee information.
[See the docs](https://docs.bitfinex.com/reference/ws-auth-trades)

This commit fixes:
`exchange Bitfinex websocket error - unable to type assert trade fee`
after an executed market trade on the te update

* Bitfinex: Fix error on ws auth ok

This fixes:
`Bitfinex Could not find an existing channel subscription: account Pair:
ChannelID: 0`
It's not clear from history why we'd want to store a reference to the
ubiquitous 0 channel like this, but it's definitely wrong, and anything
that attempts to get channel information about 0 chan needs to be fixed
anyway.

* Bitfinex: Refactor wsUpdate handling

This commit doesn't break out all the sub-updater, but attempts to do
something about the unmanagable size of ws update handling

* Binfinex: Fix linter issue on chanId casing

* Bitfinex: Fix linter outdent complaint

* Bitfinex: Fix linter issues on test

* Bitfinex: Fix TestWsTradingPairSnapshot chan lookup

* Bitfinex: Remove unnecessary WsAddSubs in test

* Bitfinex: Fix TestWsSubscribedResponse chan

* Bitfinex: Throw a specific error for bad event

* Bitfinex: WS Type assertions for positionSnapshots

* Bitfinex: tradeUpdate type assertion

* Bitfinex: Reinstate default subscriptions

* Bitfinex: Assert chan assetType is the same

* Bitfinex: Lowercase error string

* Bitfinex: Refactor WS eventType/chanId handling

* Bitfinex: Fix linter issues

* Bitfinex: Fix delimiter for pairs with more than 6 chars

* Bitfinex: Fix WS handling of subscribed symbols

This simplifies the handling of subscription symbols.
Now that we know the channel up front from handling the subscribed
response we can limit the parsing forms needed

* Bitfinex: Placate the linter

* Bitfinex: Disable margin assets for WS

Margin WS Currently not fully implemented and causes subscription collisions with spot

* Bitfinex: Fix parsing of 4 part funding keys

This improves overall handling and errors on a few current assumptions
about key structure

* Bitfinex: Linter fixes

* Bitfinex: Remove key parsing from assetPairFromSymbol

* Bitfinex: Use native error wrapping

* Bitfinex: Skip disabled assets in default ws subs

exchanges/bitfinex/bitfinex.go

@@ -21,6 +21,7 @@ import (
 	"github.com/thrasher-corp/gocryptotrader/exchanges/asset"
 	"github.com/thrasher-corp/gocryptotrader/exchanges/order"
 	"github.com/thrasher-corp/gocryptotrader/exchanges/request"
+	"github.com/thrasher-corp/gocryptotrader/exchanges/stream"
 	"github.com/thrasher-corp/gocryptotrader/portfolio/withdraw"
 )
 
@@ -105,7 +106,7 @@ const (
 // Bitfinex is the overarching type across the bitfinex package
 type Bitfinex struct {
 	exchange.Base
-	WebsocketSubdChannels map[int]WebsocketChanInfo
+	WebsocketSubdChannels map[int]*stream.ChannelSubscription
 }
 
 // GetPlatformStatus returns the Bifinex platform status

exchanges/bitfinex/bitfinex_types.go

@@ -475,12 +475,6 @@ type Fee struct {
 	MakerFees float64
 }
 
-// WebsocketChanInfo holds websocket channel information
-type WebsocketChanInfo struct {
-	Channel string
-	Pair    string
-}
-
 // WebsocketBook holds booking information
 type WebsocketBook struct {
 	ID     int64
@@ -619,6 +613,7 @@ const (
 	publicBitfinexWebsocketEndpoint        = "wss://api-pub.bitfinex.com/ws/2"
 	pong                                   = "pong"
 	wsHeartbeat                            = "hb"
+	wsChecksum                             = "cs"
 	wsPositionSnapshot                     = "ps"
 	wsPositionNew                          = "pn"
 	wsPositionUpdate                       = "pu"

exchanges/bitfinex/bitfinex_wrapper.go

@@ -59,7 +59,7 @@ func (b *Bitfinex) SetDefaults() {
 	b.Name = "Bitfinex"
 	b.Enabled = true
 	b.Verbose = true
-	b.WebsocketSubdChannels = make(map[int]WebsocketChanInfo)
+	b.WebsocketSubdChannels = make(map[int]*stream.ChannelSubscription)
 	b.API.CredentialsValidator.RequiresKey = true
 	b.API.CredentialsValidator.RequiresSecret = true
 
@@ -85,6 +85,13 @@ func (b *Bitfinex) SetDefaults() {
 	if err != nil {
 		log.Errorln(log.ExchangeSys, err)
 	}
+
+	// Margin WS Currently not fully implemented and causes subscription collisions with spot
+	err = b.DisableAssetWebsocketSupport(asset.Margin)
+	if err != nil {
+		log.Errorln(log.ExchangeSys, err)
+	}
+
 	// TODO: Implement Futures and Securities asset types.
 
 	b.Features = exchange.Features{