feat(dev_reload): use jurigged to hot reload changes to Python source (#4313)

docs/contributing/LOCAL_DEVELOPMENT.md

@@ -35,18 +35,17 @@ access.
 
 ## Backend
 
-The backend is contained within the `./invokeai/backend` folder structure. To
+The backend is contained within the `./invokeai/backend` and `./invokeai/app` directories.
-get started however please install the development dependencies.
+To get started please install the development dependencies.
 
 From the root of the repository run the following command. Note the use of `"`.
 
 ```zsh
-pip install ".[test]"
+pip install ".[dev,test]"
 ```
 
-This in an optional group of packages which is defined within the
+These are optional groups of packages which are defined within the `pyproject.toml`
-`pyproject.toml` and will be required for testing the changes you make the the
+and will be required for testing the changes you make to the code.
-code.
 
 ### Running Tests
 
@@ -76,6 +75,20 @@ pytest --cov; open ./coverage/html/index.html
 
     ![html-detail](../assets/contributing/html-detail.png)
 
+### Reloading Changes
+
+Experimenting with changes to the Python source code is a drag if you have to re-start the server —
+and re-load those multi-gigabyte models —
+after every change.
+
+For a faster development workflow, add the `--dev_reload` flag when starting the server.
+The server will watch for changes to all the Python files in the `invokeai` directory and apply those changes to the
+running server on the fly.
+
+This will allow you to avoid restarting the server (and reloading models) in most cases, but there are some caveats; see
+the [jurigged documentation](https://github.com/breuleux/jurigged#caveats) for details.
+
+
 ## Front End
 
 <!--#TODO: get input from blessedcoolant here, for the moment inserted the frontend README via snippets extension.-->

invokeai/app/api_app.py

@@ -1,11 +1,11 @@
 # Copyright (c) 2022-2023 Kyle Schouviller (https://github.com/kyle0654) and the InvokeAI Team
 import asyncio
-from inspect import signature
-
 import logging
-import uvicorn
 import socket
+from inspect import signature
+from pathlib import Path
 
+import uvicorn
 from fastapi import FastAPI
 from fastapi.middleware.cors import CORSMiddleware
 from fastapi.openapi.docs import get_redoc_html, get_swagger_ui_html
@@ -13,7 +13,6 @@ from fastapi.openapi.utils import get_openapi
 from fastapi.staticfiles import StaticFiles
 from fastapi_events.handlers.local import local_handler
 from fastapi_events.middleware import EventHandlerASGIMiddleware
-from pathlib import Path
 from pydantic.schema import schema
 
 from .services.config import InvokeAIAppConfig
@@ -30,9 +29,12 @@ from .api.sockets import SocketIO
 from .invocations.baseinvocation import BaseInvocation, _InputField, _OutputField, UIConfigBase
 
 import torch
+
+# noinspection PyUnresolvedReferences
 import invokeai.backend.util.hotfixes  # noqa: F401 (monkeypatching on import)
 
 if torch.backends.mps.is_available():
+    # noinspection PyUnresolvedReferences
     import invokeai.backend.util.mps_fixes  # noqa: F401 (monkeypatching on import)
 
 
@@ -40,7 +42,6 @@ app_config = InvokeAIAppConfig.get_config()
 app_config.parse_args()
 logger = InvokeAILogger.getLogger(config=app_config)
 
-
 # fix for windows mimetypes registry entries being borked
 # see https://github.com/invoke-ai/InvokeAI/discussions/3684#discussioncomment-6391352
 mimetypes.add_type("application/javascript", ".js")
@@ -208,6 +209,17 @@ def invoke_api():
 
     check_invokeai_root(app_config)  # note, may exit with an exception if root not set up
 
+    if app_config.dev_reload:
+        try:
+            import jurigged
+        except ImportError as e:
+            logger.error(
+                'Can\'t start `--dev_reload` because jurigged is not found; `pip install -e ".[dev]"` to include development dependencies.',
+                exc_info=e,
+            )
+        else:
+            jurigged.watch(logger=InvokeAILogger.getLogger(name="jurigged").info)
+
     port = find_port(app_config.port)
     if port != app_config.port:
         logger.warn(f"Port {app_config.port} in use, using port {port}")

invokeai/app/services/config/invokeai_config.py

@@ -169,11 +169,13 @@ two configs are kept in separate sections of the config file:
 
 """
 from __future__ import annotations
+
 import os
-from omegaconf import OmegaConf, DictConfig
 from pathlib import Path
+from typing import ClassVar, Dict, List, Literal, Union, get_type_hints, Optional
+
+from omegaconf import OmegaConf, DictConfig
 from pydantic import Field, parse_obj_as
-from typing import ClassVar, Dict, List, Literal, Union, Optional, get_type_hints
 
 from .base import InvokeAISettings
 
@@ -233,6 +235,8 @@ class InvokeAIAppConfig(InvokeAISettings):
     log_format          : Literal['plain', 'color', 'syslog', 'legacy'] = Field(default="color", description='Log format. Use "plain" for text-only, "color" for colorized output, "legacy" for 2.3-style logging and "syslog" for syslog-style', category="Logging")
     log_level           : Literal["debug", "info", "warning", "error", "critical"] = Field(default="info", description="Emit logging messages at this level or  higher", category="Logging")
 
+    dev_reload          : bool = Field(default=False, description="Automatically reload when Python sources are changed.", category="Development")
+
     version             : bool = Field(default=False, description="Show InvokeAI version and exit", category="Other")
 
     # CACHE

pyproject.toml

@@ -93,6 +93,7 @@ dependencies = [
   "mkdocs-redirects==1.2.0",
 ]
 "dev" = [
+  "jurigged",
   "pudb",
 ]
 "test" = [