Coinbase: Update exchange implementation (#1480)

* Slight enhance of Coinbase tests

Continual enhance of Coinbase tests

The revamp continues

Oh jeez the Orderbook part's unfinished don't look

Coinbase revamp, Orderbook still unfinished

* Coinbase revamp; CreateReport is still WIP

* More coinbase improvements; onto sandbox testing

* Coinbase revamp continues

* Coinbase revamp continues

* Coinbasepro revamp is ceaseless

* Coinbase revamp, starting on advanced trade API

* Coinbase Advanced Trade Starts in Ernest

V3 done, onto V2

Coinbase revamp nears completion

Coinbase revamp nears completion

Test commit should fail

Coinbase revamp nears completion

* Coinbase revamp stage wrapper

* Coinbase wrapper coherence continues

* Coinbase wrapper continues writhing

* Coinbase wrapper & codebase cleanup

* Coinbase updates & wrap progress

* More Coinbase wrapper progress

* Wrapper is wrapped, kinda

* Test & type checking

* Coinbase REST revamp finished

* Post-merge fix

* WS revamp begins

* WS Main Revamp Done?

* CB websocket tidying up

* Coinbase WS wrapperupperer

* Coinbase revamp done??

* Linter progress

* Continued lint cleanup

* Further lint cleanup

* Increased lint coverage

* Does this fix all sloppy reassigns & shadowing?

* Undoing retry policy change

* Documentation regeneration

* Coinbase code improvements

* Providing warning about known issue

* Updating an error to new format

* Making gocritic happy

* Review adherence

* Endpoints moved to V3 & nil pointer fixes

* Removing seemingly superfluous constant

* Glorious improvements

* Removing unused error

* Partial public endpoint addition

* Slight improvements

* Wrapper improvements; still a few errors left in other packages

* A lil Coinbase progress

* Json cleaning

* Lint appeasement

* Config repair

* Config fix (real)

* Little fix

* New public endpoint incorporation

* Additional fixes

* Improvements & Appeasements

* LineSaver

* Additional fixes

* Another fix

* Fixing picked nits

* Quick fixies

* Lil fixes

* Subscriptions: Add List.Enabled

* CoinbasePro: Add subscription templating

* fixup! CoinbasePro: Add subscription templating

* fixup! CoinbasePro: Add subscription templating

* Comment fix

* Subsequent fixes

* Issues hopefully fixed

* Lint fix

* Glorious fixes

* Json formatting

* ShazNits

* (L/N)i(n/)t

* Adding a test

* Tiny test improvement

* Template patch testing

* Fixes

* Further shaznits

* Lint nit

* JWT move and other fixes

* Small nits

* Shaznit, singular

* Post-merge fix

* Post-merge fixes

* Typo fix

* Some glorious nits

* Required changes

* Stop going

* Alias attempt

* Alias fix & test cleanup

* Test fix

* GetDepositAddress logic improvement

* Status update: Fixed

* Lint fix

* Happy birthday to PR 1480

* Cleanups

* Necessary nit corrections

* Fixing sillybug

* As per request

* Programming progress

* Order fixes

* Further fixies

* Test fix

* Pre-merge fixes

* More shaznits

* Context

* Sonic error handling

* Import fix

* Better Sonic error handling

* Perfect Sonic error handling?

* F purge

* Coinbase improvements

* API Update Conformity

* Coinbase continuation

* Coinbase order improvements

* Coinbase order improvements

* CreateOrderConfig improvements

* Managing API updates

* Coinbase API update progression

* jwt rename

* Comment link fix

* Coinbase v2 cleanup

* Post-merge fixes

* Review fixes

* GK's suggestions

* Linter fix

* Minor gbjk fixes

* Nit fixes

* Merge fix

* Lint fixes

* Coinbase rename stage 1

* Coinbase rename stage 2

* Coinbase rename stage 3

* Coinbase rename stage 4

* Coinbase rename final fix

* Coinbase: PoC on converting to request structs

* Applying requested changes

* Many review fixes, handled

* Thrashed by nits

* More minor modifications

* The last nit!?

---------

Co-authored-by: Gareth Kirwan <gbjkirwan@gmail.com>

engine/exchange_manager.go

@@ -7,6 +7,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/thrasher-corp/gocryptotrader/common"
 	exchange "github.com/thrasher-corp/gocryptotrader/exchanges"
 	"github.com/thrasher-corp/gocryptotrader/log"
 )
@@ -17,7 +18,6 @@ var (
 	ErrExchangeNotFound      = errors.New("exchange not found")
 	ErrExchangeAlreadyLoaded = errors.New("exchange already loaded")
 	ErrExchangeFailedToLoad  = errors.New("exchange failed to load")
-	ErrExchangeNameIsEmpty   = errors.New("exchange name is empty")
 
 	errExchangeIsNil = errors.New("exchange is nil")
 )
@@ -81,7 +81,7 @@ func (m *ExchangeManager) RemoveExchange(exchangeName string) error {
 	}
 
 	if exchangeName == "" {
-		return fmt.Errorf("exchange manager: %w", ErrExchangeNameIsEmpty)
+		return fmt.Errorf("exchange manager: %w", common.ErrExchangeNameNotSet)
 	}
 
 	m.mtx.Lock()
@@ -105,7 +105,7 @@ func (m *ExchangeManager) GetExchangeByName(exchangeName string) (exchange.IBotE
 		return nil, fmt.Errorf("exchange manager: %w", ErrNilSubsystem)
 	}
 	if exchangeName == "" {
-		return nil, fmt.Errorf("exchange manager: %w", ErrExchangeNameIsEmpty)
+		return nil, fmt.Errorf("exchange manager: %w", common.ErrExchangeNameNotSet)
 	}
 	m.mtx.Lock()
 	defer m.mtx.Unlock()