engine: Adds shutdown method to exchange manager and unload all exchanges when engine is stopped (#1112)

* engine: shutdown and unload exchange when engine is stopped

* linter: fixes

* engine/exchMan: add nil check

* engine/exchanges: add shutdown method to exchanges, rm len check lock not needed, expanded code coverage, address some nits

* exchMan: report all failed shutdowns across exchanges, implement timer and monitoring routines.

* exchMan: improve shutdown sequence and aloc.

* further improvement

* exchman: log from warn to error

* websockconnection: Suppress error return when closure is caused by library

* linter: fix

* fix racies

* add note on why not parallel tests

* glorious: nits

* spelling kween

* thrasher: nits

* engine: change print of setting using reflection, I keep forgetting to implement this so program around forgetfulness

* engine/exchange_management: remove wait group and just rely on intermediary lock

* glorious: nits

* Update common/common.go

Co-authored-by: Adrian Gallagher <adrian.gallagher@thrasher.io>

* Update main.go

Co-authored-by: Adrian Gallagher <adrian.gallagher@thrasher.io>

---------

Co-authored-by: Ryan O'Hara-Reid <ryan.oharareid@thrasher.io>
Co-authored-by: Adrian Gallagher <adrian.gallagher@thrasher.io>

common/common.go

@@ -19,6 +19,7 @@ import (
 	"strings"
 	"sync"
 	"time"
+	"unicode"
 
 	"github.com/thrasher-corp/gocryptotrader/common/file"
 	"github.com/thrasher-corp/gocryptotrader/log"
@@ -412,6 +413,37 @@ func SplitStringSliceByLimit(in []string, limit uint) [][]string {
 	return sliceSlice
 }
 
+// AddPaddingOnUpperCase adds padding to a string when detecting an upper case letter. If
+// there are multiple upper case items like `ThisIsHTTPExample`, it will only
+// pad between like this `This Is HTTP Example`.
+func AddPaddingOnUpperCase(s string) string {
+	if s == "" {
+		return ""
+	}
+	var result []string
+	left := 0
+	for x := 0; x < len(s); x++ {
+		if x == 0 {
+			continue
+		}
+
+		if unicode.IsUpper(rune(s[x])) {
+			if !unicode.IsUpper(rune(s[x-1])) {
+				result = append(result, s[left:x])
+				left = x
+			}
+		} else if x > 1 && unicode.IsUpper(rune(s[x-1])) {
+			if s[left:x-1] == "" {
+				continue
+			}
+			result = append(result, s[left:x-1])
+			left = x - 1
+		}
+	}
+	result = append(result, s[left:])
+	return strings.Join(result, " ")
+}
+
 // InArray checks if _val_ belongs to _array_
 func InArray(val, array interface{}) (exists bool, index int) {
 	exists = false

common/common_test.go

@@ -583,6 +583,37 @@ func TestSplitStringSliceByLimit(t *testing.T) {
 	}
 }
 
+func TestAddPaddingOnUpperCase(t *testing.T) {
+	t.Parallel()
+
+	testCases := []struct {
+		Supplied string
+		Expected string
+	}{
+		{
+			// empty
+		},
+		{
+			Supplied: "ExpectedHTTPRainbow",
+			Expected: "Expected HTTP Rainbow",
+		},
+		{
+			Supplied: "SmellyCatSmellsBad",
+			Expected: "Smelly Cat Smells Bad",
+		},
+		{
+			Supplied: "Gronk",
+			Expected: "Gronk",
+		},
+	}
+
+	for x := range testCases {
+		if received := AddPaddingOnUpperCase(testCases[x].Supplied); received != testCases[x].Expected {
+			t.Fatalf("received '%v' but expected '%v'", received, testCases[x].Expected)
+		}
+	}
+}
+
 func TestInArray(t *testing.T) {
 	t.Parallel()
 	InArray(nil, nil)