We were not handling node preparation errors as node errors before. Here's the explanation, copied from a comment that is no longer required:
---
TODO(psyche): Sessions only support errors on nodes, not on the session itself. When an error occurs outside
node execution, it bubbles up to the processor where it is treated as a queue item error.
Nodes are pydantic models. When we prepare a node in `session.next()`, we set its inputs. This can cause a
pydantic validation error. For example, consider a resize image node which has a constraint on its `width`
input field - it must be greater than zero. During preparation, if the width is set to zero, pydantic will
raise a validation error.
When this happens, it breaks the flow before `invocation` is set. We can't set an error on the invocation
because we didn't get far enough to get it - we don't know its id. Hence, we just set it as a queue item error.
---
This change wraps the node preparation step with exception handling. A new `NodeInputError` exception is raised when there is a validation error. This error has the node (in the state it was in just prior to the error) and an identifier of the input that failed.
This allows us to mark the node that failed preparation as errored, correctly making such errors _node_ errors and not _processor_ errors. It's much easier to diagnose these situations. The error messages look like this:
> Node b5ac87c6-0678-4b8c-96b9-d215aee12175 has invalid incoming input for height
Some of the exception handling logic is cleaned up.
- Use protocol to define callbacks, this allows them to have kwargs
- Shuffle the profiler around a bit
- Move `thread_limit` and `polling_interval` to `__init__`; `start` is called programmatically and will never get these args in practice
- Add `OnNodeError` and `OnNonFatalProcessorError` callbacks
- Move all session/node callbacks to `SessionRunner` - this ensures we dump perf stats before resetting them and generally makes sense to me
- Remove `complete` event from `SessionRunner`, it's essentially the same as `OnAfterRunSession`
- Remove extraneous `next_invocation` block, which would treat a processor error as a node error
- Simplify loops
- Add some callbacks for testing, to be removed before merge
The session is never updated in the queue after it is first enqueued. As a result, the queue detail view in the frontend never never updates and the session itself doesn't show outputs, execution graph, etc.
We need a new method on the queue service to update a queue item's session, then call it before updating the queue item's status.
Queue item status may be updated via a session-type event _or_ queue-type event. Adding the updated session to all these events is a hairy - simpler to just update the session before we do anything that could trigger a queue item status change event:
- Before calling `emit_session_complete` in the processor (handles session error, completed and cancel events and the corresponding queue events)
- Before calling `cancel_queue_item` in the processor (handles another way queue items can be canceled, outside the session execution loop)
When serializing the session, both in the new service method and the `get_queue_item` endpoint, we need to use `exclude_none=True` to prevent unexpected validation errors.
Canvas images are saved by uploading a blob generated from the HTML canvas element. This means the existing metadata handling, inside the graph execution engine, is not available.
To save metadata to canvas images, we need to provide it when uploading that blob.
The upload route now has a `metadata` body param. If this is provided, we use it over any metadata embedded in the image.
Graph, metadata and workflow all take stringified JSON only. This makes the API consistent and means we don't need to do a round-trip of pydantic parsing when handling this data.
It also prevents a failure mode where an uploaded image's metadata, workflow or graph are old and don't match the current schema.
As before, the frontend does strict validation and parsing when loading these values.
The previous super-minimal implementation had a major issue - the saved workflow didn't take into account batched field values. When generating with multiple iterations or dynamic prompts, the same workflow with the first prompt, seed, etc was stored in each image.
As a result, when the batch results in multiple queue items, only one of the images has the correct workflow - the others are mismatched.
To work around this, we can store the _graph_ in the image metadata (alongside the workflow, if generated via workflow editor). When loading a workflow from an image, we can choose to load the workflow or the graph, preferring the workflow.
Internally, we need to update images router image-saving services. The changes are minimal.
To avoid pydantic errors deserializing the graph, when we extract it from the image, we will leave it as stringified JSON and let the frontend's more sophisticated and flexible parsing handle it. The worklow is also changed to just return stringified JSON, so the API is consistent.
These simplify loading multiple LoRAs. Instead of requiring chained lora loader nodes, configure each LoRA (model & weight) with a selector, collect them, then send the collection to the collection loader to apply all of the LoRAs to the UNet/CLIP models.
The collection loaders accept a single lora or collection of loras.
There were some invalid constraints with the processors - minimum of 0 for resolution or multiple of 64 for resolution.
Made minimum 1px and no multiple ofs.
`PC_PATH_MAX` doesn't exist for (some?) external drives on macOS. We need error handling when retrieving this value.
Also added error handling for `PC_NAME_MAX` just in case. This does work for me for external drives on macOS, though.
Closes#6277
- Use the our adaptation of the HWC3 function with better types
- Extraction some of the util functions, name them better, add comments
- Improve type annotations
- Remove unreachable codepaths
