feat: add OpenAI as provider for text and image generation

- Add openai_text.py: text generation via OpenAI chat completions API
  (gpt-4o, gpt-4o-mini, gpt-4.1, gpt-4.1-mini, gpt-4.1-nano, o3-mini)
- Add openai_image.py: image generation via OpenAI images API
  (gpt-image-1 with reference image support, dall-e-3, dall-e-2)
- Refactor builder provider dispatch from TargetType to model-name index
  to support multiple providers per target type
- Fix circular import between config.py and providers/__init__.py
  using TYPE_CHECKING guard
- Fix stale default model assertions in tests
- Add openai>=1.0.0 dependency
This commit is contained in:
Konstantin Fickel 2026-02-15 13:48:06 +01:00
parent d0dac5b1bf
commit 870023865d
Signed by: kfickel
GPG key ID: A793722F9933C1A5
9 changed files with 571 additions and 58 deletions

View file

@ -9,16 +9,14 @@ from collections.abc import Callable
from dataclasses import dataclass, field
from pathlib import Path
from bulkgen.config import (
ProjectConfig,
TargetType,
target_type_from_capabilities,
)
from bulkgen.config import ProjectConfig
from bulkgen.graph import build_graph, get_build_order, get_subgraph_for_target
from bulkgen.providers import Provider
from bulkgen.providers.blackforest import BlackForestProvider
from bulkgen.providers.mistral import MistralProvider
from bulkgen.resolve import infer_required_capabilities, resolve_model
from bulkgen.providers.openai_image import OpenAIImageProvider
from bulkgen.providers.openai_text import OpenAITextProvider
from bulkgen.resolve import resolve_model
from bulkgen.state import (
BuildState,
is_target_dirty,
@ -100,32 +98,43 @@ def _collect_all_deps(target_name: str, config: ProjectConfig) -> list[str]:
return deps
def _create_providers() -> dict[TargetType, Provider]:
def _create_providers() -> list[Provider]:
"""Create provider instances from environment variables."""
providers: dict[TargetType, Provider] = {}
providers: list[Provider] = []
bfl_key = os.environ.get("BFL_API_KEY", "")
if bfl_key:
providers[TargetType.IMAGE] = BlackForestProvider(api_key=bfl_key)
providers.append(BlackForestProvider(api_key=bfl_key))
mistral_key = os.environ.get("MISTRAL_API_KEY", "")
if mistral_key:
providers[TargetType.TEXT] = MistralProvider(api_key=mistral_key)
providers.append(MistralProvider(api_key=mistral_key))
openai_key = os.environ.get("OPENAI_API_KEY", "")
if openai_key:
providers.append(OpenAITextProvider(api_key=openai_key))
providers.append(OpenAIImageProvider(api_key=openai_key))
return providers
def _build_provider_index(providers: list[Provider]) -> dict[str, Provider]:
"""Build a model-name → provider lookup from a list of providers."""
index: dict[str, Provider] = {}
for provider in providers:
for model in provider.get_provided_models():
index[model.name] = provider
return index
async def _build_single_target(
target_name: str,
config: ProjectConfig,
project_dir: Path,
providers: dict[TargetType, Provider],
provider_index: dict[str, Provider],
) -> None:
"""Build a single target by dispatching to the appropriate provider."""
target_cfg = config.targets[target_name]
model_info = resolve_model(target_name, target_cfg, config.defaults)
required = infer_required_capabilities(target_name, target_cfg)
target_type = target_type_from_capabilities(required)
resolved_prompt = _resolve_prompt(target_cfg.prompt, project_dir)
provider = providers[target_type]
provider = provider_index[model_info.name]
await provider.generate(
target_name=target_name,
target_config=target_cfg,
@ -152,6 +161,7 @@ async def run_build(
"""
result = BuildResult()
providers = _create_providers()
provider_index = _build_provider_index(providers)
graph = build_graph(config, project_dir)
@ -181,7 +191,7 @@ async def run_build(
continue
if _is_dirty(name, config, project_dir, state):
if not _has_provider(name, config, providers, result, on_progress):
if not _has_provider(name, config, provider_index, result, on_progress):
continue
dirty_targets.append(name)
else:
@ -195,7 +205,7 @@ async def run_build(
on_progress(BuildEvent.TARGET_BUILDING, name, "")
outcomes = await _build_generation(
dirty_targets, config, project_dir, providers
dirty_targets, config, project_dir, provider_index
)
_process_outcomes(outcomes, config, project_dir, state, result, on_progress)
@ -238,19 +248,15 @@ def _is_dirty(
def _has_provider(
target_name: str,
config: ProjectConfig,
providers: dict[TargetType, Provider],
provider_index: dict[str, Provider],
result: BuildResult,
on_progress: ProgressCallback = _noop_callback,
) -> bool:
"""Check that the required provider is available; record failure if not."""
target_cfg = config.targets[target_name]
required = infer_required_capabilities(target_name, target_cfg)
target_type = target_type_from_capabilities(required)
if target_type not in providers:
env_var = (
"BFL_API_KEY" if target_type is TargetType.IMAGE else "MISTRAL_API_KEY"
)
msg = f"Missing {env_var} environment variable"
model_info = resolve_model(target_name, target_cfg, config.defaults)
if model_info.name not in provider_index:
msg = f"No provider available for model '{model_info.name}' (provider: {model_info.provider}) — check API key environment variables"
result.failed[target_name] = msg
on_progress(BuildEvent.TARGET_NO_PROVIDER, target_name, msg)
return False
@ -261,13 +267,13 @@ async def _build_generation(
dirty_targets: list[str],
config: ProjectConfig,
project_dir: Path,
providers: dict[TargetType, Provider],
provider_index: dict[str, Provider],
) -> list[tuple[str, Exception | None]]:
"""Build all dirty targets in a generation concurrently."""
async def _build_one(name: str) -> tuple[str, Exception | None]:
try:
await _build_single_target(name, config, project_dir, providers)
await _build_single_target(name, config, project_dir, provider_index)
except Exception as exc: # noqa: BLE001
return (name, exc)
return (name, None)

View file

@ -4,10 +4,13 @@ from __future__ import annotations
import abc
from pathlib import Path
from typing import TYPE_CHECKING
from bulkgen.config import TargetConfig
from bulkgen.providers.models import ModelInfo
if TYPE_CHECKING:
from bulkgen.config import TargetConfig
class Provider(abc.ABC):
"""Abstract base for generation providers."""

View file

@ -0,0 +1,194 @@
"""OpenAI image generation provider."""
from __future__ import annotations
import base64
from pathlib import Path
from typing import Literal, override
import httpx
from openai import AsyncOpenAI
from openai.types.images_response import ImagesResponse
from bulkgen.config import TargetConfig
from bulkgen.providers import Provider
from bulkgen.providers.models import Capability, ModelInfo
_SIZE = Literal[
"auto",
"1024x1024",
"1024x1536",
"1536x1024",
"1024x1792",
"1792x1024",
"256x256",
"512x512",
]
_VALID_SIZES: frozenset[str] = frozenset(
{
"auto",
"1024x1024",
"1024x1536",
"1536x1024",
"1024x1792",
"1792x1024",
"256x256",
"512x512",
}
)
def _build_size(width: int | None, height: int | None) -> _SIZE | None:
"""Convert width/height to an OpenAI size string, or *None* for the default."""
if width is None and height is None:
return None
w = width or 1024
h = height or 1024
size = f"{w}x{h}"
if size not in _VALID_SIZES:
msg = f"Unsupported OpenAI image size '{size}'. Valid sizes: {', '.join(sorted(_VALID_SIZES))}"
raise ValueError(msg)
return size # pyright: ignore[reportReturnType]
class OpenAIImageProvider(Provider):
"""Generates images via the OpenAI API."""
_api_key: str
def __init__(self, api_key: str) -> None:
self._api_key = api_key
@staticmethod
@override
def get_provided_models() -> list[ModelInfo]:
return [
ModelInfo(
name="gpt-image-1",
provider="OpenAI",
type="image",
capabilities=[
Capability.TEXT_TO_IMAGE,
Capability.REFERENCE_IMAGES,
],
),
ModelInfo(
name="dall-e-3",
provider="OpenAI",
type="image",
capabilities=[Capability.TEXT_TO_IMAGE],
),
ModelInfo(
name="dall-e-2",
provider="OpenAI",
type="image",
capabilities=[Capability.TEXT_TO_IMAGE],
),
]
@override
async def generate(
self,
target_name: str,
target_config: TargetConfig,
resolved_prompt: str,
resolved_model: ModelInfo,
project_dir: Path,
) -> None:
output_path = project_dir / target_name
size = _build_size(target_config.width, target_config.height)
async with AsyncOpenAI(api_key=self._api_key) as client:
if target_config.reference_images:
response = await _generate_edit(
client,
resolved_prompt,
resolved_model.name,
target_config.reference_images,
project_dir,
size,
)
else:
response = await _generate_new(
client,
resolved_prompt,
resolved_model.name,
size,
)
image_data = _extract_image_bytes(response, resolved_model.name)
_ = output_path.write_bytes(image_data)
async def _generate_new(
client: AsyncOpenAI,
prompt: str,
model: str,
size: _SIZE | None,
) -> ImagesResponse:
"""Generate a new image from a text prompt."""
if size is not None:
return await client.images.generate(
prompt=prompt,
model=model,
n=1,
response_format="b64_json",
size=size,
)
return await client.images.generate(
prompt=prompt,
model=model,
n=1,
response_format="b64_json",
)
async def _generate_edit(
client: AsyncOpenAI,
prompt: str,
model: str,
reference_images: list[str],
project_dir: Path,
size: _SIZE | None,
) -> ImagesResponse:
"""Generate an image using a reference image via the edits endpoint."""
ref_path = project_dir / reference_images[0]
image_bytes = ref_path.read_bytes()
if size is not None:
return await client.images.edit(
image=image_bytes,
prompt=prompt,
model=model,
n=1,
response_format="b64_json",
size=size, # pyright: ignore[reportArgumentType]
)
return await client.images.edit(
image=image_bytes,
prompt=prompt,
model=model,
n=1,
response_format="b64_json",
)
def _extract_image_bytes(response: ImagesResponse, model: str) -> bytes:
"""Extract image bytes from an OpenAI images response."""
if not response.data:
msg = f"OpenAI {model} returned no images"
raise RuntimeError(msg)
image = response.data[0]
if image.b64_json is not None:
return base64.b64decode(image.b64_json)
if image.url is not None:
resp = httpx.get(image.url)
_ = resp.raise_for_status()
return resp.content
msg = f"OpenAI {model} returned neither b64_json nor url"
raise RuntimeError(msg)

View file

@ -0,0 +1,169 @@
"""OpenAI text generation provider."""
from __future__ import annotations
import base64
import mimetypes
from pathlib import Path
from typing import override
from openai import AsyncOpenAI
from openai.types.chat import (
ChatCompletionContentPartImageParam,
ChatCompletionContentPartParam,
ChatCompletionContentPartTextParam,
ChatCompletionUserMessageParam,
)
from bulkgen.config import IMAGE_EXTENSIONS, TargetConfig
from bulkgen.providers import Provider
from bulkgen.providers.models import Capability, ModelInfo
def _image_to_data_url(path: Path) -> str:
"""Read an image file and return a ``data:`` URL with base64-encoded content."""
mime = mimetypes.guess_type(path.name)[0] or "image/png"
b64 = base64.b64encode(path.read_bytes()).decode("ascii")
return f"data:{mime};base64,{b64}"
class OpenAITextProvider(Provider):
"""Generates text via the OpenAI API."""
_api_key: str
def __init__(self, api_key: str) -> None:
self._api_key = api_key
@staticmethod
@override
def get_provided_models() -> list[ModelInfo]:
return [
ModelInfo(
name="gpt-4o",
provider="OpenAI",
type="text",
capabilities=[Capability.TEXT_GENERATION, Capability.VISION],
),
ModelInfo(
name="gpt-4o-mini",
provider="OpenAI",
type="text",
capabilities=[Capability.TEXT_GENERATION, Capability.VISION],
),
ModelInfo(
name="gpt-4.1",
provider="OpenAI",
type="text",
capabilities=[Capability.TEXT_GENERATION, Capability.VISION],
),
ModelInfo(
name="gpt-4.1-mini",
provider="OpenAI",
type="text",
capabilities=[Capability.TEXT_GENERATION, Capability.VISION],
),
ModelInfo(
name="gpt-4.1-nano",
provider="OpenAI",
type="text",
capabilities=[Capability.TEXT_GENERATION, Capability.VISION],
),
ModelInfo(
name="o3-mini",
provider="OpenAI",
type="text",
capabilities=[Capability.TEXT_GENERATION],
),
]
@override
async def generate(
self,
target_name: str,
target_config: TargetConfig,
resolved_prompt: str,
resolved_model: ModelInfo,
project_dir: Path,
) -> None:
output_path = project_dir / target_name
all_input_names = list(target_config.inputs) + list(
target_config.reference_images
)
has_images = any(
(project_dir / name).suffix.lower() in IMAGE_EXTENSIONS
for name in all_input_names
)
if has_images:
message = _build_multimodal_message(
resolved_prompt, all_input_names, project_dir
)
else:
message = _build_text_message(resolved_prompt, all_input_names, project_dir)
async with AsyncOpenAI(api_key=self._api_key) as client:
response = await client.chat.completions.create(
model=resolved_model.name,
messages=[message],
)
if not response.choices:
msg = f"OpenAI API returned no choices for target '{target_name}'"
raise RuntimeError(msg)
content = response.choices[0].message.content
if content is None:
msg = f"OpenAI API returned empty content for target '{target_name}'"
raise RuntimeError(msg)
_ = output_path.write_text(content)
def _build_text_message(
prompt: str,
input_names: list[str],
project_dir: Path,
) -> ChatCompletionUserMessageParam:
"""Build a plain-text message (no images)."""
parts: list[str] = [prompt]
for name in input_names:
file_content = (project_dir / name).read_text()
parts.append(f"\n--- Contents of {name} ---\n{file_content}")
return {"role": "user", "content": "\n".join(parts)}
def _build_multimodal_message(
prompt: str,
input_names: list[str],
project_dir: Path,
) -> ChatCompletionUserMessageParam:
"""Build a multimodal message with text and image parts."""
parts: list[ChatCompletionContentPartParam] = [
ChatCompletionContentPartTextParam(type="text", text=prompt),
]
for name in input_names:
input_path = project_dir / name
suffix = input_path.suffix.lower()
if suffix in IMAGE_EXTENSIONS:
data_url = _image_to_data_url(input_path)
parts.append(
ChatCompletionContentPartImageParam(
type="image_url",
image_url={"url": data_url},
)
)
else:
file_content = input_path.read_text()
parts.append(
ChatCompletionContentPartTextParam(
type="text",
text=f"\n--- Contents of {name} ---\n{file_content}",
)
)
return {"role": "user", "content": parts}

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@ -9,8 +9,12 @@ def get_all_models() -> list[ModelInfo]:
"""Return the merged list of models from all providers."""
from bulkgen.providers.blackforest import BlackForestProvider
from bulkgen.providers.mistral import MistralProvider
from bulkgen.providers.openai_image import OpenAIImageProvider
from bulkgen.providers.openai_text import OpenAITextProvider
return (
MistralProvider.get_provided_models()
+ BlackForestProvider.get_provided_models()
+ OpenAITextProvider.get_provided_models()
+ OpenAIImageProvider.get_provided_models()
)