Improve initial load error handling

index.html

@@ -79,6 +79,14 @@
         #splash__error {
             margin-top: 2rem;
             transition: opacity 0.5s ease-in;
+            display: flex;
+            flex-direction: column;
+            text-align: center;
+            max-width: 60rem;
+        }
+
+        #splash__error-message {
+            font-family: monospace;
         }
 
         #splash__error[aria-hidden=true] {
@@ -125,7 +133,9 @@
         </svg>
 
         <div id="splash__error" role="alert" aria-hidden="true">
-            Failed to load server configuration. Retrying<span id="splash__error-attempt"></span>...
+            <span>Failed to load server configuration.</span>
+            <span id="splash__error-message"></span>
+            <span id="splash__error-retry">Retrying<span id="splash__error-attempt"></span>...</span>
         </div>
     </div>
 

public/index.html

@@ -81,6 +81,10 @@
             transition: opacity 0.5s ease-in;
         }
 
+        #splash__error-message {
+            font-family: monospace;
+        }
+
         #splash__error[aria-hidden=true] {
             opacity: 0;
         }

src/App.vue

@@ -29,6 +29,7 @@ import {useStore} from "@/store";
 import {ActionTypes} from "@/store/action-types";
 import {parseUrl} from '@/util';
 import {MutationTypes} from "@/store/mutation-types";
+import API from '@/api';
 
 export default defineComponent({
 	name: 'App',
@@ -50,15 +51,24 @@ export default defineComponent({
 			configAttempts = ref(0),
 
 			loadConfiguration = () => {
-				store.dispatch(ActionTypes.LOAD_CONFIGURATION, undefined).then(() => {
-					startUpdates();
-					window.hideSplash();
+				let validated = false;
+
+				API.validateConfiguration().then(() => {
+					validated = true;
+
+					return store.dispatch(ActionTypes.LOAD_CONFIGURATION, undefined).then(() => {
+						startUpdates();
+						window.hideSplash();
+					});
 				}).catch(e => {
 					console.error('Failed to load server configuration: ', e);
-					window.showSplashError(++configAttempts.value);
+					window.showSplashError(e, !validated, ++configAttempts.value);
 
-					setTimeout(() => loadConfiguration(), 1000);
-				});
+					//Don't retry if config isn't valid
+					if(validated) {
+						setTimeout(() => loadConfiguration(), 1000);
+					}
+				})
 			},
 
 			startUpdates = () => {

src/api.ts

@@ -553,10 +553,40 @@ function buildUpdates(data: Array<any>): DynmapUpdates {
 }
 
 export default {
+	validateConfiguration(): Promise<void> {
+		const check = '\nCheck your standalone/config.js file exists and is being loaded correctly.';
+
+		if(!window.config || !window.config.url) {
+			return Promise.reject(`Dynmap's configuration is missing. ${check}`);
+		}
+
+		if(!window.config.url.configuration) {
+			return Promise.reject(`Dynmap's configuration URL is missing. ${check}`);
+		}
+
+		if(!window.config.url.update) {
+			return Promise.reject(`Dynmap's update URL is missing. ${check}`);
+		}
+
+		if(!window.config.url.markers) {
+			return Promise.reject(`Dynmap's markers URL is missing. ${check}`);
+		}
+
+		if(!window.config.url.tiles) {
+			return Promise.reject(`Dynmap's tiles URL is missing. ${check}`);
+		}
+
+		if(!window.config.url.sendmessage) {
+			return Promise.reject(`Dynmap's sendmessage URL is missing. ${check}`);
+		}
+
+		return Promise.resolve();
+	},
+
 	getConfiguration(): Promise<DynmapConfigurationResponse> {
 		return fetch(window.config.url.configuration).then(response => {
 			if (!response.ok) {
-				throw new Error('Network request failed');
+				throw new Error('Network request failed: ' + response.statusText);
 			}
 
 			return response.json();

src/main.ts

@@ -23,7 +23,10 @@ import 'normalize-scss/sass/normalize/_import-now.scss';
 import '@/scss/style.scss';
 
 const splash = document.getElementById('splash'),
+	splashSpinner = document.getElementById('splash__spinner'),
 	splashError = document.getElementById('splash__error'),
+	splashErrorMessage = document.getElementById('splash__error-message'),
+	splashRetry = document.getElementById('splash__error-retry'),
 	splashAttempt = document.getElementById('splash__error-attempt'),
 	svgs = import.meta.globEager('/assets/icons/*.svg');
 
@@ -35,13 +38,26 @@ window.hideSplash = function() {
 	});
 };
 
-window.showSplashError = function(attempts: number) {
+window.showSplashError = function(message: string, fatal: boolean, attempts: number) {
 	if(splashError) {
 		splashError.setAttribute('aria-hidden', 'false');
 	}
 
-	if(splashAttempt) {
-		splashAttempt.textContent = attempts.toString();
+	if(splashErrorMessage) {
+		splashErrorMessage.innerText = message || 'Unknown error';
+	}
+
+	if(splashSpinner && fatal) {
+		splashSpinner.style.visibility = 'hidden';
+	}
+
+	if(splashAttempt && splashRetry) {
+		if(fatal) {
+			splashAttempt.hidden = splashRetry.hidden = true;
+		} else if(attempts) {
+			splashAttempt.hidden = splashRetry.hidden = false;
+			splashAttempt.textContent = attempts.toString();
+		}
 	}
 };