Websocket reconnection fix (#541)

* Adds potential fix for websocket reconnection failure

* Addr tests, we now don't return an error, this allows us to reuse existing if still in operation.

* update depends && go mod tidy

* adds in channel direction for parameter

* Add full subscriber function, increased test coverage, initiate go routine after calling routine instance check in connection monitor

* fix linter issue

* use protected methods for setting field variables

* removed function, added tests

* lock sub manipulation

* fix linter issue

* Added in transport idleconnection timeout to fix MACOS reconnection issue when all idle connections are consuming resources

* used protected methods to set underlying fields

* set variable via time.Duration param

* Added in lock around field variable in test

* Addr thrasher nits and expanded exchange tests

* Fix test

* Addr glorious nits

* go mod tidy

* Add a larger timeout for traffic monitor if the test runs slow

common/common.go

@@ -51,10 +51,18 @@ func initialiseHTTPClient() {
 	}
 }
 
-// NewHTTPClientWithTimeout initialises a new HTTP client with the specified
-// timeout duration
+// NewHTTPClientWithTimeout initialises a new HTTP client and its underlying
+// transport IdleConnTimeout with the specified timeout duration
 func NewHTTPClientWithTimeout(t time.Duration) *http.Client {
-	h := &http.Client{Timeout: t}
+	tr := &http.Transport{
+		// Added IdleConnTimeout to reduce the time of idle connections which
+		// could potentially slow macOS reconnection when there is a sudden
+		// network disconnection/issue
+		IdleConnTimeout: t,
+	}
+	h := &http.Client{
+		Transport: tr,
+		Timeout:   t}
 	return h
 }