fix: block workflow queue when file input nodes have empty selections

Prevents submitting workflows where LoadImage, LoadAudio, Load3D, or
LoadVideo nodes have no file selected. Shows a localized error dialog
listing the affected nodes instead of sending an invalid request.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/locales/en/main.json

@@ -1889,7 +1889,9 @@
     "extensionFileHint": "This may be due to the following script",
     "promptExecutionError": "Prompt execution failed",
     "accessRestrictedTitle": "Access Restricted",
-    "accessRestrictedMessage": "Your account is not authorized for this feature."
+    "accessRestrictedMessage": "Your account is not authorized for this feature.",
+    "emptyFileInputTitle": "Missing File Inputs",
+    "emptyFileInputMessage": "The following nodes require a file to be selected: {nodeList}. Please upload or select files before running."
   },
   "apiNodesSignInDialog": {
     "title": "Sign In Required to Use API Nodes",

src/scripts/app.ts

@@ -146,6 +146,30 @@ import {
 
 export const ANIM_PREVIEW_WIDGET = '$$comfy_animation_preview'
 
+export const FILE_INPUT_FIELDS: Record<string, string> = {
+  LoadImage: 'image',
+  LoadAudio: 'audio',
+  Load3D: 'model_file',
+  LoadVideo: 'video'
+}
+
+export function findEmptyFileInputNodes(
+  output: ComfyApiWorkflow
+): { nodeId: string; classType: string; title: string }[] {
+  const result: { nodeId: string; classType: string; title: string }[] = []
+  for (const [nodeId, node] of Object.entries(output)) {
+    const field = FILE_INPUT_FIELDS[node.class_type]
+    if (field && node.inputs[field] === '') {
+      result.push({
+        nodeId,
+        classType: node.class_type,
+        title: node._meta?.title ?? node.class_type
+      })
+    }
+  }
+  return result
+}
+
 export function sanitizeNodeName(string: string) {
   let entityMap = {
     '&': '',
@@ -1615,6 +1639,21 @@ export class ComfyApp {
           const queuedWorkflow = useWorkspaceStore().workflow
             .activeWorkflow as ComfyWorkflow
           const p = await this.graphToPrompt(this.rootGraph)
+
+          const emptyFileInputNodes = findEmptyFileInputNodes(p.output)
+          if (emptyFileInputNodes.length) {
+            const nodeList = emptyFileInputNodes
+              .map((n) => `#${n.nodeId} ${n.title}`)
+              .join(', ')
+            useDialogService().showErrorDialog(
+              new Error(
+                t('errorDialog.emptyFileInputMessage', { nodeList })
+              ),
+              { title: t('errorDialog.emptyFileInputTitle') }
+            )
+            break
+          }
+
           const queuedNodes = collectAllNodes(this.rootGraph)
           try {
             api.authToken = comfyOrgAuthToken

src/scripts/findEmptyFileInputNodes.test.ts

@@ -0,0 +1,73 @@
+import { describe, expect, it } from 'vitest'
+
+import type { ComfyApiWorkflow } from '@/platform/workflow/validation/schemas/workflowSchema'
+import { findEmptyFileInputNodes } from './app'
+
+function makeNode(
+  classType: string,
+  inputs: Record<string, unknown>,
+  title?: string
+) {
+  return {
+    class_type: classType,
+    inputs,
+    _meta: { title: title ?? classType }
+  }
+}
+
+describe('findEmptyFileInputNodes', () => {
+  it('detects LoadImage with empty image field', () => {
+    const output: ComfyApiWorkflow = {
+      '1': makeNode('LoadImage', { image: '' }),
+      '2': makeNode('KSampler', { seed: 42 })
+    }
+    expect(findEmptyFileInputNodes(output)).toEqual([
+      { nodeId: '1', classType: 'LoadImage', title: 'LoadImage' }
+    ])
+  })
+
+  it('detects multiple empty file input nodes', () => {
+    const output: ComfyApiWorkflow = {
+      '1': makeNode('LoadImage', { image: '' }, 'My Image'),
+      '2': makeNode('LoadAudio', { audio: '' }),
+      '3': makeNode('LoadVideo', { video: 'file.mp4' })
+    }
+    const result = findEmptyFileInputNodes(output)
+    expect(result).toHaveLength(2)
+    expect(result[0]).toEqual({
+      nodeId: '1',
+      classType: 'LoadImage',
+      title: 'My Image'
+    })
+    expect(result[1]).toEqual({
+      nodeId: '2',
+      classType: 'LoadAudio',
+      title: 'LoadAudio'
+    })
+  })
+
+  it('returns empty array when all file inputs are populated', () => {
+    const output: ComfyApiWorkflow = {
+      '1': makeNode('LoadImage', { image: 'photo.png' }),
+      '2': makeNode('Load3D', { model_file: 'model.glb' })
+    }
+    expect(findEmptyFileInputNodes(output)).toEqual([])
+  })
+
+  it('returns empty array when no file input nodes exist', () => {
+    const output: ComfyApiWorkflow = {
+      '1': makeNode('KSampler', { seed: 42 }),
+      '2': makeNode('CLIPTextEncode', { text: 'hello' })
+    }
+    expect(findEmptyFileInputNodes(output)).toEqual([])
+  })
+
+  it('detects Load3D with empty model_file', () => {
+    const output: ComfyApiWorkflow = {
+      '5': makeNode('Load3D', { model_file: '' })
+    }
+    expect(findEmptyFileInputNodes(output)).toEqual([
+      { nodeId: '5', classType: 'Load3D', title: 'Load3D' }
+    ])
+  })
+})