feat(client): ✨ add function to test connection on ip update

client/index.html

@@ -116,7 +116,7 @@
 
 		document
 			.querySelector('#settings')
-			.addEventListener('submit', (event) => {
+			.addEventListener('submit', async (event) => {
 				// Don't interrupt event if not form submitting
 				if (!(event instanceof SubmitEvent)) return true
 				if (event.target === null) return true
@@ -128,9 +128,38 @@
 
 				if (ipAddress === null) return
 
-				setEndpoint(`http://${ipAddress}`)
+				const endpoint = `http://${ipAddress}`
+				await testEndpoint(endpoint)
+				setEndpoint(endpoint)
 			})
 
+		/**
+		 * Test connection to endpoint.
+		 * 
+		 * @param {string} endpoint Endpoint to test for.
+		 * 
+		 * @returns {void}
+		 * @throws {Error} Endpoint unreachable.
+		 */
+		async function testEndpoint(endpoint) {
+			try {
+				const response = await fetch(endpoint)
+				if (response.ok) return
+			} catch (cause) {
+				alert(`Impossible de joindre l'adresse "${endpoint}"`)
+				throw new Error(`unable to connect to robot at ${endpoint}`, {
+					cause,
+				})
+			}
+		}
+
+		document.addEventListener('keydown', (event) => {
+			const key = event.keyCode
+			const { command, value } = keyMap[key]
+			const endpoint = getEndpoint()
+			sendCommand(endpoint, command, value)
+		})
+
 		function storeInput() {
 			ipInput = document.getElementById('ip').value
 			valueRot = document.getElementById('valueRot').value