chore: remove optional imports in v2 (#4855)

* remove optional imports in v2

* unused import

haystack/preview/dataclasses/document.py

@@ -1,4 +1,4 @@
-from typing import List, Any, Dict, Literal, Optional, TYPE_CHECKING
+from typing import List, Any, Dict, Literal, Optional
 
 import json
 import hashlib
@@ -6,20 +6,20 @@ import logging
 from pathlib import Path
 from dataclasses import asdict, dataclass, field
 
-from haystack.preview.utils.import_utils import optional_import
-
-# We need to do this dance because ndarray is an optional dependency used as a type by dataclass
-if TYPE_CHECKING:
-    from numpy import ndarray
-else:
-    ndarray = optional_import("numpy", "ndarray", "You won't be able to use embeddings.", __name__)
-
-DataFrame = optional_import("pandas", "DataFrame", "You won't be able to use table related features.", __name__)
+import numpy
+import pandas
 
 
 logger = logging.getLogger(__name__)
+
 ContentType = Literal["text", "table", "image", "audio"]
-PYTHON_TYPES_FOR_CONTENT: Dict[ContentType, type] = {"text": str, "table": DataFrame, "image": Path, "audio": Path}
+
+PYTHON_TYPES_FOR_CONTENT: Dict[ContentType, type] = {
+    "text": str,
+    "table": pandas.DataFrame,
+    "image": Path,
+    "audio": Path,
+}
 
 
 def _create_id(
@@ -61,7 +61,7 @@ class Document:
     metadata: Dict[str, Any] = field(default_factory=dict, hash=False)
     id_hash_keys: List[str] = field(default_factory=lambda: [], hash=False)
     score: Optional[float] = field(default=None, compare=True)
-    embedding: Optional[ndarray] = field(default=None, repr=False)
+    embedding: Optional[numpy.ndarray] = field(default=None, repr=False)
 
     def __str__(self):
         return f"{self.__class__.__name__}('{self.content}')"

haystack/preview/utils/import_utils.py

@@ -1,24 +0,0 @@
-from typing import Optional, Any
-import importlib
-import logging
-
-
-def optional_import(import_path: str, import_target: Optional[str], error_msg: str, importer_module: str) -> Any:
-    """
-    Imports an optional dependency. Emits a DEBUG log if the dependency is missing.
-    """
-    try:
-        module = importlib.import_module(import_path)
-        if import_target:
-            return getattr(module, import_target)
-        return module
-    except ImportError as exc:
-        logging.getLogger(importer_module).debug(
-            "%s%s%s can't be imported: %s Error raised: %s",
-            import_path,
-            "." if import_target else "",
-            import_target,
-            error_msg,
-            exc,
-        )
-        return None