feat(backend): move pagination models to own file

invokeai/app/services/shared/pagination.py

@@ -0,0 +1,42 @@
+from typing import Generic, TypeVar
+
+from pydantic import BaseModel, Field
+from pydantic.generics import GenericModel
+
+GenericBaseModel = TypeVar("GenericBaseModel", bound=BaseModel)
+
+
+class CursorPaginatedResults(GenericModel, Generic[GenericBaseModel]):
+    """
+    Cursor-paginated results
+    Generic must be a Pydantic model
+    """
+
+    limit: int = Field(..., description="Limit of items to get")
+    has_more: bool = Field(..., description="Whether there are more items available")
+    items: list[GenericBaseModel] = Field(..., description="Items")
+
+
+class OffsetPaginatedResults(GenericModel, Generic[GenericBaseModel]):
+    """
+    Offset-paginated results
+    Generic must be a Pydantic model
+    """
+
+    limit: int = Field(description="Limit of items to get")
+    offset: int = Field(description="Offset from which to retrieve items")
+    total: int = Field(description="Total number of items in result")
+    items: list[GenericBaseModel] = Field(description="Items")
+
+
+class PaginatedResults(GenericModel, Generic[GenericBaseModel]):
+    """
+    Paginated results
+    Generic must be a Pydantic model
+    """
+
+    page: int = Field(description="Current Page")
+    pages: int = Field(description="Total number of pages")
+    per_page: int = Field(description="Number of items per page")
+    total: int = Field(description="Total number of items in result")
+    items: list[GenericBaseModel] = Field(description="Items")