feat: nomic embed v1.5 hf embeddings (#10762)

llama-index-integrations/embeddings/llama-index-embeddings-nomic/llama_index/embeddings/nomic/base.py

 from enum import Enum
-from typing import Any, List, Optional
+from typing import Any, List, Optional, Union
 
-from llama_index.core.base.embeddings.base import BaseEmbedding
+from llama_index.core.base.embeddings.base import (
+    BaseEmbedding,
+    DEFAULT_EMBED_BATCH_SIZE,
+)
 from llama_index.core.bridge.pydantic import Field, PrivateAttr
 from llama_index.core.callbacks import CallbackManager
 
+from llama_index.embeddings.huggingface import HuggingFaceEmbedding
+
+from llama_index.core.bridge.pydantic import Field, PrivateAttr
+from llama_index.embeddings.huggingface.pooling import Pooling
+import torch
+import logging
+
+DEFAULT_HUGGINGFACE_LENGTH = 512
+logger = logging.getLogger(__name__)
+
 
 class NomicAITaskType(str, Enum):
     SEARCH_QUERY = "search_query"
@@ -109,3 +122,106 @@ class NomicEmbedding(BaseEmbedding):
     def _get_text_embeddings(self, texts: List[str]) -> List[List[float]]:
         """Get text embeddings."""
         return self._embed(texts, task_type=self.document_task_type)
+
+
+class NomicHFEmbedding(HuggingFaceEmbedding):
+    tokenizer_name: str = Field(description="Tokenizer name from HuggingFace.")
+    max_length: int = Field(
+        default=DEFAULT_HUGGINGFACE_LENGTH, description="Maximum length of input.", gt=0
+    )
+    pooling: Pooling = Field(default=Pooling.MEAN, description="Pooling strategy.")
+    normalize: bool = Field(default=True, description="Normalize embeddings or not.")
+    query_instruction: Optional[str] = Field(
+        description="Instruction to prepend to query text."
+    )
+    text_instruction: Optional[str] = Field(
+        description="Instruction to prepend to text."
+    )
+    cache_folder: Optional[str] = Field(
+        description="Cache folder for huggingface files."
+    )
+    dimensionality: Optional[int] = Field(description="Dimensionality of embedding")
+
+    _model: Any = PrivateAttr()
+    _tokenizer: Any = PrivateAttr()
+    _device: str = PrivateAttr()
+
+    def __init__(
+        self,
+        model_name: Optional[str] = None,
+        tokenizer_name: Optional[str] = None,
+        pooling: Union[str, Pooling] = "cls",
+        max_length: Optional[int] = None,
+        query_instruction: Optional[str] = None,
+        text_instruction: Optional[str] = None,
+        normalize: bool = True,
+        model: Optional[Any] = None,
+        tokenizer: Optional[Any] = None,
+        embed_batch_size: int = DEFAULT_EMBED_BATCH_SIZE,
+        cache_folder: Optional[str] = None,
+        trust_remote_code: bool = False,
+        device: Optional[str] = None,
+        callback_manager: Optional[CallbackManager] = None,
+        dimensionality: int = 768,
+    ):
+        super().__init__(
+            model_name=model_name,
+            tokenizer_name=tokenizer_name,
+            pooling=pooling,
+            max_length=max_length,
+            query_instruction=query_instruction,
+            text_instruction=text_instruction,
+            normalize=normalize,
+            model=model,
+            tokenizer=tokenizer,
+            embed_batch_size=embed_batch_size,
+            cache_folder=cache_folder,
+            trust_remote_code=trust_remote_code,
+            device=device,
+            callback_manager=callback_manager,
+        )
+        self.dimensionality = dimensionality
+        self._model.eval()
+
+    def _embed(self, sentences: List[str]) -> List[List[float]]:
+        """Embed sentences."""
+        encoded_input = self._tokenizer(
+            sentences,
+            padding=True,
+            max_length=self.max_length,
+            truncation=True,
+            return_tensors="pt",
+        )
+
+        # pop token_type_ids
+        encoded_input.pop("token_type_ids", None)
+
+        # move tokenizer inputs to device
+        encoded_input = {
+            key: val.to(self._device) for key, val in encoded_input.items()
+        }
+
+        with torch.no_grad():
+            model_output = self._model(**encoded_input)
+
+        if self.pooling == Pooling.CLS:
+            context_layer: "torch.Tensor" = model_output[0]
+            embeddings = self.pooling.cls_pooling(context_layer)
+        else:
+            embeddings = self._mean_pooling(
+                token_embeddings=model_output[0],
+                attention_mask=encoded_input["attention_mask"],
+            )
+
+        if self.normalize:
+            import torch.nn.functional as F
+
+            if self.model_name == "nomic-ai/nomic-embed-text-v1.5":
+                emb_ln = F.layer_norm(
+                    embeddings, normalized_shape=(embeddings.shape[1],)
+                )
+                embeddings = emb_ln[:, : self.dimensionality]
+
+            embeddings = F.normalize(embeddings, p=2, dim=1)
+
+        return embeddings.tolist()

llama-index-integrations/embeddings/llama-index-embeddings-nomic/pyproject.toml

@@ -29,6 +29,9 @@ version = "0.1.1"
 [tool.poetry.dependencies]
 python = ">=3.8.1,<3.12"
 llama-index-core = "^0.10.1"
+llama-index-embeddings-huggingface = "^0.1.0"
+einops = "^0.7.0"
+nomic = "^3.0.12"
 
 [tool.poetry.group.dev.dependencies]
 ipython = "8.10.0"