feat: add completions-based OpenAI bot (#39)

Author: mtth

README.md

@@ -5,11 +5,7 @@
 
 ## Highlights
 
-* Concurrent editing. Continue editing while the assistant runs, without any
+* Concurrent edits. Continue editing while the assistant runs, without any
   risks of interference.
-
-
-## Ideas
-
-* Add a compatibility OpenAI bot version which does not use threads, so that it
-  can be used with tools only. Gemini only supports the latter.
+* Customizable prompt templates
+* Extensible bot API

src/git_draft/__main__.py

@@ -111,15 +111,13 @@ def main() -> None:
     )
     command = getattr(opts, "command", "generate")
     if command == "generate":
-        if not config.bots:
-            raise ValueError("No bots configured")
-
+        bot_config = None
         if opts.bot:
             bot_configs = [c for c in config.bots if c.name == opts.bot]
             if len(bot_configs) != 1:
                 raise ValueError(f"Found {len(bot_configs)} matching bots")
             bot_config = bot_configs[0]
-        else:
+        elif config.bots:
             bot_config = config.bots[0]
         bot = load_bot(bot_config)
 

src/git_draft/bots/__init__.py

@@ -4,9 +4,10 @@
 """
 
 import importlib
+import os
 import sys
 
-from ..common import BotConfig
+from ..common import BotConfig, reindent
 from .common import Action, Bot, Goal, Operation, OperationHook, Toolbox
 
 __all__ = [
@@ -19,20 +20,11 @@
 ]
 
 
-def load_bot(config: BotConfig) -> Bot:
-    """Load and return a Bot instance using the provided configuration.
+def load_bot(config: BotConfig | None) -> Bot:
+    """Load and return a Bot instance using the provided configuration"""
+    if not config:
+        return _default_bot()
 
-    If a pythonpath is specified in the config and not already present in
-    sys.path, it is added. The function expects the config.factory in the
-    format 'module:symbol' or 'symbol'. If only 'symbol' is provided, the
-    current module is used.
-
-    Args:
-        config: BotConfig object containing bot configuration details.
-
-    Raises:
-        NotImplementedError: If the specified factory cannot be found.
-    """
     if config.pythonpath and config.pythonpath not in sys.path:
         sys.path.insert(0, config.pythonpath)
 
@@ -44,7 +36,36 @@ def load_bot(config: BotConfig) -> Bot:
 
     factory = getattr(module, symbol, None)
     if not factory:
-        raise NotImplementedError(f"Unknown bot factory: {factory}")
+        raise NotImplementedError(f"Unknown bot factory: {config.factory}")
 
     kwargs = config.config or {}
     return factory(**kwargs)
+
+
+def _default_bot() -> Bot:
+    if not os.environ.get("OPENAI_API_KEY"):
+        raise RuntimeError(
+            reindent(
+                """
+                    The default bot implementation requires an OpenAI API key.
+                    Please specify one via the `$OPENAI_API_KEY` environment
+                    variable or enable a different bot in your configuration.
+                """
+            )
+        )
+
+    try:
+        from .openai import threads_bot
+
+    except ImportError:
+        raise RuntimeError(
+            reindent(
+                """
+                    The default bot implementation requires the `openai` Python
+                    package. Please install it or specify a different bot in
+                    your configuration.
+                """
+            )
+        )
+    else:
+        return threads_bot()