added into generated client response handlers

src/javascript.tpl.php

@@ -8,6 +8,8 @@
 class <?php echo $this->apiName; ?> {
 	endpoint = <?php echo sprintf(substr($this->endpoint, 0, 4) == 'http' ? '"%s"' : '%s', $this->endpoint); ?>;
 	bearerStorageKey = 'apilite_bearer_token';
+	responseHandlers = [];
+	errorHandlers = [];
 
 	normalizeBearerToken(token) {
 		if (typeof token !== 'string') return null;
@@ -58,20 +60,64 @@ class <?php echo $this->apiName; ?> {
 		storage.setItem(this.bearerStorageKey, token);
 	}
 
+	addResponseHandler(handler) {
+		this.responseHandlers.push(handler);
+		return () => {
+			this.responseHandlers = this.responseHandlers.filter(registeredHandler => registeredHandler !== handler);
+		};
+	}
+
+	addErrorHandler(handler) {
+		this.errorHandlers.push(handler);
+		return () => {
+			this.errorHandlers = this.errorHandlers.filter(registeredHandler => registeredHandler !== handler);
+		};
+	}
+
+	emitResponseHandlers(response, context) {
+		this.responseHandlers.forEach(handler => {
+			try {
+				handler(response, context);
+			} catch (error) {
+				// Response handlers must not change the API request result.
+			}
+		});
+	}
+
+	emitErrorHandlers(response, context) {
+		this.errorHandlers.forEach(handler => {
+			try {
+				handler(response, context);
+			} catch (error) {
+				// Error handlers must not change the API request result.
+			}
+		});
+	}
+
+	emitHandlers(response, context) {
+		this.emitResponseHandlers(response, context);
+		if (response.status === 'ERROR') this.emitErrorHandlers(response, context);
+	}
+
 	/* ----------------------------------------------------
 	 * General API call
 	 */
 	call(method, data, callback) {
 		var xhttp = new XMLHttpRequest();
 		var headers = this.getRequestHeaders();
+		var api = this;
 		xhttp.withCredentials = true;
 		xhttp.onreadystatechange = function() {
 			if (this.readyState === 4) {
+				var response;
 				if (this.status === 200) {
-					if (callback != null) callback(JSON.parse(this.responseText));
+					response = JSON.parse(this.responseText);
 				} else {
-					if (callback != null) callback({'status': 'ERROR', 'msg': 'HTTP STATUS ' + this.status});
+					response = {'status': 'ERROR', 'msg': 'HTTP STATUS ' + this.status};
 				}
+				var context = {method: method, data: data, httpStatus: this.status};
+				api.emitHandlers(response, context);
+				if (callback != null) callback(response);
 			}
 		}
 		var form_data  = new FormData();
@@ -118,4 +164,4 @@ class <?php echo $this->apiName; ?> {
 
 };
 
-export default new <?php echo $this->apiName; ?>();
+export default new <?php echo $this->apiName; ?>();