Vertex Save Config

A small utility node with one job: persist the config objects floating around your workflow to a JSON file on disk. It's the "export" end of the pack's config system, and its partner VertexLoadConfig is the "import."

You use it when a setup is worth keeping. Say you've tuned a VertexGenerationConfig and spent a run getting VertexAIAuth just right - save them, and the next time you rebuild a workflow you can pull the whole thing back from a dropdown instead of re-entering credentials and parameters by hand. Since VertexAIAuth already auto-saves its own config on first run, this node's real value is capturing the generation side (and, if you like, an explicit copy of the auth config) together in one file.

How it works

The mechanism is dead simple, and one detail is worth knowing. Give it a filename_prefix and it writes a JSON file named <unix-timestamp>_<prefix>.json into the pack's config/ folder. That timestamp prefix means every run writes a new file - it never overwrites, so a long session of experimenting will quietly accumulate config files. It's tidy (they're small), but if you want one canonical file, you'll be pruning the folder.

It's an output node (OUTPUT_NODE = True), so it acts as a workflow endpoint. Its inputs:

• filename_prefix (string, default vertex_config) - the human-readable part of the filename.
• vertex_config (optional) - plug in the output of VertexAIAuth to save credentials + project settings.
• generation_config (optional) - plug in the output of VertexGenerationConfig to save sampling parameters.

It returns a single filepath string pointing at the written file - handy if you want to see where it landed or feed the path into something else. Whatever you connected, it merges into one JSON document; files written this way are exactly what VertexLoadConfig's dropdown and VertexAIAuth's config_file input read back.

Installing it

Same pack, same install - ComfyUI Manager → search comfyUI_Vertex_API, or clone https://github.com/linfen0/comfyUI_Vertex_API.git into custom_nodes/, pip install -r requirements.txt, restart.

The honest take

There's not much to say about this node that isn't obvious, and that's fine - it's the boring piece of plumbing that makes the config system survivable. Two habits will save you grief: give files meaningful prefixes (the timestamp already handles uniqueness), and remember your saved config lives in plaintext inside the pack folder, so treat it like any other file holding credentials.