autoset base_url if empty

frontend/src/lib/components/InstanceSettings.svelte

@@ -51,7 +51,12 @@
 				await Promise.all(
 					Object.entries(settings).map(
 						async ([_, y]) =>
-							await Promise.all(y.map(async (x) => [x.key, await getValue(x.key, x.storage)]))
+							await Promise.all(
+								y.map(async (x) => [
+									x.key,
+									(await getValue(x.key, x.storage)) ?? x.defaultValue?.()
+								])
+							)
 					)
 				)
 			).flat()
@@ -452,8 +457,7 @@
 
 											{#if hasError}
 												<span class="text-red-500 text-xs">
-													Base url must start with http:// or https:// and must NOT end with a
-													trailing slash.
+													{setting.error ?? ''}
 												</span>
 											{/if}
 										{:else}

frontend/src/lib/components/instanceSettings.ts

@@ -18,6 +18,8 @@ export interface Setting {
 		| 'license_key'
 	storage: SettingStorage
 	isValid?: (value: any) => boolean
+	error?: string
+	defaultValue?: () => any
 }
 
 export type SettingStorage = 'setting' | 'config'
@@ -32,7 +34,8 @@ export const settings: Record<string, Setting[]> = {
 			placeholder: 'https://windmill.com',
 			storage: 'setting',
 			isValid: (value: string | undefined) =>
-				value ? value?.startsWith('http') && value.includes('://') && !value?.endsWith('/') : true
+				value ? value?.startsWith('http') && value.includes('://') && !value?.endsWith('/') : true,
+			defaultValue: () => window.location.origin
 		},
 		{
 			label: 'Request Size Limit In MB',