Files

535 lines
18 KiB
Python

"""
Image Generation API 路由
"""
import base64
import time
from pathlib import Path
from typing import List, Optional, Union
from fastapi import APIRouter, File, Form, Request, UploadFile
from fastapi.responses import StreamingResponse, JSONResponse
from pydantic import BaseModel, Field, ValidationError
from app.services.grok.services.image import ImageGenerationService
from app.services.grok.services.image_edit import ImageEditService
from app.services.grok.services.model import ModelService
from app.services.token import get_token_manager
from app.core.exceptions import ValidationException, AppException, ErrorType
from app.core.config import get_config
from app.core.logger import logger
router = APIRouter(tags=["Images"])
ALLOWED_IMAGE_SIZES = {
"1280x720",
"720x1280",
"1792x1024",
"1024x1792",
"1024x1024",
}
SIZE_TO_ASPECT = {
"1280x720": "16:9",
"720x1280": "9:16",
"1792x1024": "3:2",
"1024x1792": "2:3",
"1024x1024": "1:1",
}
def _tool_error_response(exc: AppException) -> JSONResponse:
"""返回 200 业务错误,避免工具层只看到 HTTP 异常。"""
logger.warning(
"Images API business error: "
f"type={exc.error_type}, code={exc.code}, param={exc.param}, message={exc.message}"
)
return JSONResponse(
status_code=200,
content={
"created": int(time.time()),
"data": [],
"error": {
"message": exc.message,
"type": exc.error_type,
"param": exc.param,
"code": exc.code,
},
},
)
class ImageGenerationRequest(BaseModel):
"""图片生成请求 - OpenAI 兼容"""
prompt: str = Field(..., description="图片描述")
model: Optional[str] = Field("grok-imagine-1.0", description="模型名称")
n: Optional[int] = Field(1, ge=1, le=10, description="生成数量 (1-10)")
size: Optional[str] = Field(
"1024x1024",
description="图片尺寸: 1280x720, 720x1280, 1792x1024, 1024x1792, 1024x1024",
)
quality: Optional[str] = Field("standard", description="图片质量 (暂不支持)")
response_format: Optional[str] = Field(None, description="响应格式")
style: Optional[str] = Field(None, description="风格 (暂不支持)")
stream: Optional[bool] = Field(False, description="是否流式输出")
class ImageEditRequest(BaseModel):
"""图片编辑请求 - OpenAI 兼容"""
prompt: str = Field(..., description="编辑描述")
model: Optional[str] = Field("grok-imagine-1.0-edit", description="模型名称")
image: Optional[Union[str, List[str]]] = Field(None, description="待编辑图片文件")
n: Optional[int] = Field(1, ge=1, le=10, description="生成数量 (1-10)")
size: Optional[str] = Field(
"1024x1024",
description="图片尺寸: 1280x720, 720x1280, 1792x1024, 1024x1792, 1024x1024",
)
quality: Optional[str] = Field("standard", description="图片质量 (暂不支持)")
response_format: Optional[str] = Field(None, description="响应格式")
style: Optional[str] = Field(None, description="风格 (暂不支持)")
stream: Optional[bool] = Field(False, description="是否流式输出")
def _validate_common_request(
request: Union[ImageGenerationRequest, ImageEditRequest],
*,
allow_ws_stream: bool = False,
):
"""通用参数校验"""
# 验证 prompt
if not request.prompt or not request.prompt.strip():
raise ValidationException(
message="Prompt cannot be empty", param="prompt", code="empty_prompt"
)
# 验证 n 参数范围
if request.n < 1 or request.n > 10:
raise ValidationException(
message="n must be between 1 and 10", param="n", code="invalid_n"
)
# 流式只支持 n=1 或 n=2
if request.stream and request.n not in [1, 2]:
raise ValidationException(
message="Streaming is only supported when n=1 or n=2",
param="stream",
code="invalid_stream_n",
)
if allow_ws_stream:
if request.stream and request.response_format:
allowed_stream_formats = {"b64_json", "base64", "url"}
if request.response_format not in allowed_stream_formats:
raise ValidationException(
message="Streaming only supports response_format=b64_json/base64/url",
param="response_format",
code="invalid_response_format",
)
if request.response_format:
allowed_formats = {"b64_json", "base64", "url"}
if request.response_format not in allowed_formats:
raise ValidationException(
message=f"response_format must be one of {sorted(allowed_formats)}",
param="response_format",
code="invalid_response_format",
)
if request.size and request.size not in ALLOWED_IMAGE_SIZES:
raise ValidationException(
message=f"size must be one of {sorted(ALLOWED_IMAGE_SIZES)}",
param="size",
code="invalid_size",
)
def validate_generation_request(request: ImageGenerationRequest):
"""验证图片生成请求参数"""
if request.model != "grok-imagine-1.0":
raise ValidationException(
message="The model `grok-imagine-1.0` is required for image generation.",
param="model",
code="model_not_supported",
)
# 验证模型 - 通过 is_image 检查
model_info = ModelService.get(request.model)
if not model_info or not model_info.is_image:
# 获取支持的图片模型列表
image_models = [m.model_id for m in ModelService.MODELS if m.is_image]
raise ValidationException(
message=(
f"The model `{request.model}` is not supported for image generation. "
f"Supported: {image_models}"
),
param="model",
code="model_not_supported",
)
_validate_common_request(request, allow_ws_stream=True)
def resolve_response_format(response_format: Optional[str]) -> str:
"""解析响应格式"""
fmt = response_format or get_config("app.image_format")
if isinstance(fmt, str):
fmt = fmt.lower()
if fmt in ("b64_json", "base64", "url"):
return fmt
raise ValidationException(
message="response_format must be one of b64_json, base64, url",
param="response_format",
code="invalid_response_format",
)
def response_field_name(response_format: str) -> str:
"""获取响应字段名"""
return {"url": "url", "base64": "base64"}.get(response_format, "b64_json")
def resolve_aspect_ratio(size: str) -> str:
"""Map OpenAI size to Grok Imagine aspect ratio."""
size = (size or "").strip()
return SIZE_TO_ASPECT.get(size) or "2:3"
def _should_force_non_streaming(raw_request: Request) -> bool:
"""
对 OpenAI 兼容图片接口默认降级为非流式 JSON。
当前图片流使用的是自定义 `image_generation.partial_image/completed` 事件,
不符合 OpenAI 标准 chunk 结构。像 Cherry Studio 这类客户端会把每个 SSE
`data:` 块按 `choices/error` 结构校验,因此会触发 TypeValidationError。
为保证兼容性,这两个 OpenAI 风格 endpoint 默认忽略 `stream=true`。
只有显式传入私有请求头 `X-Grok2API-Image-Stream: 1` 时,才启用旧的自定义 SSE。
"""
stream_opt_in = str(
raw_request.headers.get("x-grok2api-image-stream") or ""
).strip().lower()
return stream_opt_in not in {"1", "true", "yes", "on"}
def _normalize_openai_image_stream_flag(
stream_value: Optional[bool], raw_request: Request, route_name: str
) -> bool:
"""
OpenAI 兼容图片接口默认关闭自定义 SSE。
这些 endpoint 对外声明为 OpenAI 风格,但当前流式事件不是 OpenAI 标准 chunk。
因此默认统一降级为非流式 JSON,只给明确 opt-in 的自有前端保留旧行为。
"""
if not bool(stream_value):
return False
if _should_force_non_streaming(raw_request):
logger.info(f"{route_name} fallback to non-streaming JSON")
return False
return True
def validate_edit_request(request: ImageEditRequest, images: List[UploadFile]):
"""验证图片编辑请求参数"""
if request.model != "grok-imagine-1.0-edit":
raise ValidationException(
message=("The model `grok-imagine-1.0-edit` is required for image edits."),
param="model",
code="model_not_supported",
)
model_info = ModelService.get(request.model)
if not model_info or not model_info.is_image_edit:
edit_models = [m.model_id for m in ModelService.MODELS if m.is_image_edit]
raise ValidationException(
message=(
f"The model `{request.model}` is not supported for image edits. "
f"Supported: {edit_models}"
),
param="model",
code="model_not_supported",
)
_validate_common_request(request, allow_ws_stream=False)
if request.n != 1:
raise ValidationException(
message="For image edits, n must be 1.",
param="n",
code="invalid_n",
)
if not images:
raise ValidationException(
message="Image is required",
param="image",
code="missing_image",
)
if len(images) > 3:
raise ValidationException(
message="Too many images. Maximum is 3.",
param="image",
code="invalid_image_count",
)
async def _get_token(model: str):
"""获取可用 token"""
token_mgr = await get_token_manager()
await token_mgr.reload_if_stale()
token = None
for pool_name in ModelService.pool_candidates_for_model(model):
token = token_mgr.get_token(pool_name)
if token:
break
if not token:
raise AppException(
message="No available tokens. Please try again later.",
error_type=ErrorType.RATE_LIMIT.value,
code="rate_limit_exceeded",
status_code=429,
)
return token_mgr, token
@router.post("/images/generations")
async def create_image(request: ImageGenerationRequest, raw_request: Request):
"""
Image Generation API
流式响应格式:
- event: image_generation.partial_image
- event: image_generation.completed
非流式响应格式:
- {"created": ..., "data": [{"b64_json": "..."}], "usage": {...}}
"""
try:
request.stream = _normalize_openai_image_stream_flag(
request.stream, raw_request, "Images API"
)
if request.response_format is None:
request.response_format = resolve_response_format(None)
# 参数验证
validate_generation_request(request)
# 兼容 base64/b64_json
if request.response_format == "base64":
request.response_format = "b64_json"
response_format = resolve_response_format(request.response_format)
response_field = response_field_name(response_format)
# 获取 token 和模型信息
token_mgr, token = await _get_token(request.model)
model_info = ModelService.get(request.model)
aspect_ratio = resolve_aspect_ratio(request.size)
result = await ImageGenerationService().generate(
token_mgr=token_mgr,
token=token,
model_info=model_info,
prompt=request.prompt,
n=request.n,
response_format=response_format,
size=request.size,
aspect_ratio=aspect_ratio,
stream=bool(request.stream),
)
if result.stream:
return StreamingResponse(
result.data,
media_type="text/event-stream",
headers={"Cache-Control": "no-cache", "Connection": "keep-alive"},
)
data = [{response_field: img} for img in result.data]
usage = result.usage_override or {
"total_tokens": 0,
"input_tokens": 0,
"output_tokens": 0,
"input_tokens_details": {"text_tokens": 0, "image_tokens": 0},
}
return JSONResponse(
content={
"created": int(time.time()),
"data": data,
"usage": usage,
}
)
except AppException as exc:
return _tool_error_response(exc)
except Exception as exc:
logger.exception(f"Images API unexpected error: {exc}")
return _tool_error_response(
AppException(
message="Image generation failed due to internal error",
error_type=ErrorType.SERVER.value,
code="image_internal_error",
status_code=500,
)
)
@router.post("/images/edits")
async def edit_image(
raw_request: Request,
prompt: str = Form(...),
image: Optional[List[UploadFile]] = File(None),
image_bracket: Optional[List[UploadFile]] = File(None, alias="image[]"),
model: Optional[str] = Form("grok-imagine-1.0-edit"),
n: int = Form(1),
size: str = Form("1024x1024"),
quality: str = Form("standard"),
response_format: Optional[str] = Form(None),
style: Optional[str] = Form(None),
stream: Optional[bool] = Form(False),
):
"""
Image Edits API
同官方 API 格式,仅支持 multipart/form-data 文件上传
"""
try:
if response_format is None:
response_format = resolve_response_format(None)
try:
edit_request = ImageEditRequest(
prompt=prompt,
model=model,
n=n,
size=size,
quality=quality,
response_format=response_format,
style=style,
stream=stream,
)
except ValidationError as exc:
errors = exc.errors()
if errors:
first = errors[0]
loc = first.get("loc", [])
msg = first.get("msg", "Invalid request")
code = first.get("type", "invalid_value")
param_parts = [
str(x) for x in loc if not (isinstance(x, int) or str(x).isdigit())
]
param = ".".join(param_parts) if param_parts else None
raise ValidationException(message=msg, param=param, code=code)
raise ValidationException(message="Invalid request", code="invalid_value")
edit_request.stream = _normalize_openai_image_stream_flag(
edit_request.stream, raw_request, "Image edits"
)
# 兼容两种多文件字段:image / image[]
upload_images: List[UploadFile] = []
if image:
upload_images.extend(image)
if image_bracket:
upload_images.extend(image_bracket)
response_format = resolve_response_format(edit_request.response_format)
if response_format == "base64":
response_format = "b64_json"
edit_request.response_format = response_format
response_field = response_field_name(response_format)
# 参数验证
validate_edit_request(edit_request, upload_images)
max_image_bytes = 50 * 1024 * 1024
allowed_types = {"image/png", "image/jpeg", "image/webp", "image/jpg"}
images: List[str] = []
for item in upload_images:
content = await item.read()
await item.close()
if not content:
raise ValidationException(
message="File content is empty",
param="image",
code="empty_file",
)
if len(content) > max_image_bytes:
raise ValidationException(
message="Image file too large. Maximum is 50MB.",
param="image",
code="file_too_large",
)
mime = (item.content_type or "").lower()
if mime == "image/jpg":
mime = "image/jpeg"
ext = Path(item.filename or "").suffix.lower()
if mime not in allowed_types:
if ext in (".jpg", ".jpeg"):
mime = "image/jpeg"
elif ext == ".png":
mime = "image/png"
elif ext == ".webp":
mime = "image/webp"
else:
raise ValidationException(
message="Unsupported image type. Supported: png, jpg, webp.",
param="image",
code="invalid_image_type",
)
b64 = base64.b64encode(content).decode()
images.append(f"data:{mime};base64,{b64}")
# 获取 token 和模型信息
token_mgr, token = await _get_token(edit_request.model)
model_info = ModelService.get(edit_request.model)
result = await ImageEditService().edit(
token_mgr=token_mgr,
token=token,
model_info=model_info,
prompt=edit_request.prompt,
images=images,
n=edit_request.n,
response_format=response_format,
stream=bool(edit_request.stream),
)
if result.stream:
return StreamingResponse(
result.data,
media_type="text/event-stream",
headers={"Cache-Control": "no-cache", "Connection": "keep-alive"},
)
data = [{response_field: img} for img in result.data]
return JSONResponse(
content={
"created": int(time.time()),
"data": data,
"usage": {
"total_tokens": 0,
"input_tokens": 0,
"output_tokens": 0,
"input_tokens_details": {"text_tokens": 0, "image_tokens": 0},
},
}
)
except AppException as exc:
return _tool_error_response(exc)
except Exception as exc:
logger.exception(f"Image edits unexpected error: {exc}")
return _tool_error_response(
AppException(
message="Image edit failed due to internal error",
error_type=ErrorType.SERVER.value,
code="image_edit_internal_error",
status_code=500,
)
)
__all__ = ["router"]