Backend API

APIs available to nodes for model loading, file I/O, uploads, and audio processing.

---

Model API

List Registered Models

Returns all models in the registry with their install status. Useful for checking if a required model is available before a node runs.

GET /api/models

Response:

[
  {
    "id": "yolox_s",
    "name": "YOLOX S",
    "category": "Object Detection",
    "source": { "type": "huggingface", "url": "Megvii-BaseDetection/YOLOX" },
    "installed": true
  }
]

---

List Models by Category

Lists installed model files in a specific category folder. Used by loader nodes (e.g., LoadYOLOXModelNode) to populate dropdowns.

GET /api/models/:category

Example:

GET /api/models/Object Detection

Response:

[
  { "name": "yolox_s", "path": "Object Detection/yolox_s.pth" }
]

---

Download a Model

Triggers a background download job for a registered model. Returns a job_id for polling status.

POST /api/models/download/:id

Poll for status:

GET /api/downloads/status/:job_id

Status response:

{
  "status": "running",
  "progress": 42,
  "message": "Downloading... 42%"
}

Status values: running, completed, error.

---

File API

Use these to persist data a node generates (e.g., custom workflows, presets, config files) to the libs directory.

Save a File

POST /api/files/save

{ "path": "my_node/config.json", "content": { "key": "value" } }

Read a File

GET /api/files/read?path=my_node/config.json

List Files

GET /api/files/list?path=my_node

---

Upload API

Handles chunked file uploads from widgets. When a node’s frontend uploads a file, it uses this endpoint.

POST /api/upload

Form Data fields:

Field	Description
file	Chunk blob
filename	Full filename
chunkIndex	Current chunk index
totalChunks	Total chunk count
sessionId	Session ID for file isolation
nodeId / nodeName	Used to scope upload folder to the node

On success (final chunk):

{
  "success": true,
  "completed": true,
  "filePath": "/temp/uploads/session_id/NodeName_nodeId/file.mp4"
}

---

Audio API

Trim Audio

Trim an audio file server-side using FFmpeg. Typically called from an audio node that has an AudioTrimmerModal in its widget.

POST /api/audio/trim

{
  "filePath": "/temp/uploads/.../audio.mp3",
  "start": 10.5,
  "end": 25.0,
  "sessionId": "abc123"
}

Response:

{
  "success": true,
  "filePath": "/temp/AudioTrim/audio_trimmed_1712345.mp3"
}