support inference a batch of prompts (#467)

* support inference a batch of prompts

* docstring and assert

lmdeploy/serve/async_engine.py

@@ -4,7 +4,7 @@ import dataclasses
 import os.path as osp
 import random
 from contextlib import contextmanager
-from typing import Literal, Optional
+from typing import List, Literal, Optional
 
 from lmdeploy.model import MODELS, BaseModel
 
@@ -46,6 +46,7 @@ class AsyncEngine:
         self.available = [True] * instance_num
         self.starts = [None] * instance_num
         self.steps = {}
+        self.loop = asyncio.get_event_loop()
 
     def stop_session(self, session_id: int):
         instance_id = session_id % self.instance_num
@@ -82,6 +83,59 @@ class AsyncEngine:
                 await asyncio.sleep(0.1)
         return self.generators[instance_id]
 
+    def batch_infer(self,
+                    prompts: List[str],
+                    request_output_len=512,
+                    top_k=40,
+                    top_p=0.8,
+                    temperature=0.8,
+                    repetition_penalty=1.0,
+                    ignore_eos=False,
+                    **kwargs):
+        """Inference a batch of prompts.
+
+        Args:
+            prompts (List[str]): a batch of prompts
+            request_output_len (int): output token nums
+            top_k (int): The number of the highest probability vocabulary
+              tokens to keep for top-k-filtering
+            top_p (float): If set to float < 1, only the smallest set of most
+              probable tokens with probabilities that add up to top_p or higher
+            are kept for generation.
+            temperature (float): to modulate the next token probability
+            repetition_penalty (float): The parameter for repetition penalty.
+              1.0 means no penalty
+            ignore_eos (bool): indicator for ignoring eos
+        """
+        assert isinstance(prompts, List), 'prompts should be a list'
+        batch_size = len(prompts)
+        outputs = [''] * batch_size
+        generators = []
+        for i, prompt in enumerate(prompts):
+            generators.append(
+                self.generate(prompt,
+                              i,
+                              stream_response=True,
+                              sequence_start=True,
+                              sequence_end=True,
+                              request_output_len=request_output_len,
+                              top_k=top_k,
+                              top_p=top_p,
+                              temperature=temperature,
+                              ignore_eos=ignore_eos,
+                              repetition_penalty=repetition_penalty))
+
+        async def _inner_call(i, generator):
+            async for out in generator:
+                outputs[i] += out.response
+
+        async def gather():
+            await asyncio.gather(
+                *[_inner_call(i, generators[i]) for i in range(batch_size)])
+
+        self.loop.run_until_complete(gather())
+        return outputs
+
     async def generate(
         self,
         messages,
@@ -109,11 +163,11 @@ class AsyncEngine:
             sequence_end (bool): indicator for ending a sequence
             step (int): the offset of the k/v cache
             stop (bool): whether stop inference
-            top_p (float): If set to float < 1, only the smallest set of most
-              probable tokens with probabilities that add up to top_p or higher
-            are kept for generation.
             top_k (int): The number of the highest probability vocabulary
               tokens to keep for top-k-filtering
+            top_p (float): If set to float < 1, only the smallest set of most
+              probable tokens with probabilities that add up to top_p or higher
+              are kept for generation.
             temperature (float): to modulate the next token probability
             repetition_penalty (float): The parameter for repetition penalty.
               1.0 means no penalty
@@ -195,11 +249,11 @@ class AsyncEngine:
             renew_session (bool): renew the session
             request_output_len (int): output token nums
             stop (bool): whether stop inference
-            top_p (float): If set to float < 1, only the smallest set of most
-              probable tokens with probabilities that add up to top_p or higher
-            are kept for generation.
             top_k (int): The number of the highest probability vocabulary
               tokens to keep for top-k-filtering
+            top_p (float): If set to float < 1, only the smallest set of most
+              probable tokens with probabilities that add up to top_p or higher
+              are kept for generation.
             temperature (float): to modulate the next token probability
             repetition_penalty (float): The parameter for repetition penalty.
               1.0 means no penalty

lmdeploy/serve/openai/api_server.py

@@ -229,11 +229,19 @@ async def create_embeddings(request: EmbeddingsRequest,
     error_check_ret = await check_request(request)
     if error_check_ret is not None:
         return error_check_ret
-
-    embedding = await VariableInterface.async_engine.get_embeddings(
-        request.input)
-    data = [{'object': 'embedding', 'embedding': embedding, 'index': 0}]
-    token_num = len(embedding)
+    if isinstance(request.input, str):
+        request.input = [request.input]
+
+    data = []
+    token_num = 0
+    for i, prompt in enumerate(request.input):
+        embedding = await VariableInterface.async_engine.get_embeddings(prompt)
+        data.append({
+            'object': 'embedding',
+            'embedding': embedding,
+            'index': i
+        })
+        token_num += len(embedding)
     return EmbeddingsResponse(
         data=data,
         model=request.model,

lmdeploy/serve/openai/protocol.py

@@ -175,7 +175,7 @@ class CompletionStreamResponse(BaseModel):
 class EmbeddingsRequest(BaseModel):
     """Embedding request."""
     model: str = None
-    input: Union[str, List[Any]]
+    input: Union[str, List[str]]
     user: Optional[str] = None