Add openai Completion adapter (#202)

Signed-off-by: shiyu22 <shiyu.chen@zilliz.com>

gptcache/adapter/openai.py

@@ -4,7 +4,11 @@
 import openai
 
 from gptcache.adapter.adapter import adapt
-from gptcache.utils.response import get_message_from_openai_answer, get_stream_message_from_openai_answer
+from gptcache.utils.response import (
+    get_stream_message_from_openai_answer,
+    get_message_from_openai_answer,
+    get_text_from_openai_answer,
+)
 
 
 class ChatCompletion:
@@ -84,3 +88,39 @@ def construct_stream_resp_from_cache(return_message):
             "object": "chat.completion.chunk",
         },
     ]
+
+
+class Completion:
+    """Openai Completion Wrapper"""
+
+    @classmethod
+    def create(cls, *args, **kwargs):
+        def llm_handler(*llm_args, **llm_kwargs):
+            return openai.Completion.create(*llm_args, **llm_kwargs)
+
+        def cache_data_convert(cache_data):
+            return construct_text_from_cache(cache_data)
+
+        def update_cache_callback(llm_data, update_cache_func):
+            update_cache_func(get_text_from_openai_answer(llm_data))
+            return llm_data
+
+        return adapt(
+            llm_handler, cache_data_convert, update_cache_callback, *args, **kwargs
+        )
+
+
+def construct_text_from_cache(return_text):
+    return {
+        "gptcache": True,
+        "choices": [
+            {
+                "text": return_text,
+                "finish_reason": "stop",
+                "index": 0,
+            }
+        ],
+        "created": int(time.time()),
+        "usage": {"completion_tokens": 0, "prompt_tokens": 0, "total_tokens": 0},
+        "object": "text_completion",
+    }

gptcache/utils/response.py

@@ -4,3 +4,7 @@ def get_message_from_openai_answer(openai_resp):
 
 def get_stream_message_from_openai_answer(openai_data):
     return openai_data["choices"][0]["delta"].get("content", "")
+
+
+def get_text_from_openai_answer(openai_resp):
+    return openai_resp["choices"][0]["text"]

tests/unit_tests/adapter/test_openai.py

@@ -2,9 +2,11 @@
 from gptcache.utils.response import (
     get_stream_message_from_openai_answer,
     get_message_from_openai_answer,
+    get_text_from_openai_answer,
 )
 from gptcache.adapter import openai
 from gptcache import cache
+from gptcache.processor.pre import get_prompt
 
 
 def test_stream_openai():
@@ -78,3 +80,36 @@ def test_stream_openai():
     )
     answer_text = get_message_from_openai_answer(response)
     assert answer_text == expect_answer, answer_text
+
+
+def test_completion():
+    cache.init(pre_embedding_func=get_prompt)
+    question = "what is your name?"
+    expect_answer = "gptcache"
+
+    with patch("openai.Completion.create") as mock_create:
+        mock_create.return_value = {
+            "choices": [
+                {"text": expect_answer,
+                 "finish_reason": None,
+                 "index": 0}
+            ],
+            "created": 1677825464,
+            "id": "cmpl-6ptKyqKOGXZT6iQnqiXAH8adNLUzD",
+            "model": "text-davinci-003",
+            "object": "text_completion",
+        }
+
+        response = openai.Completion.create(
+            model="text-davinci-003",
+            prompt=question
+        )
+        answer_text = get_text_from_openai_answer(response)
+        assert answer_text == expect_answer
+
+    response = openai.Completion.create(
+        model="text-davinci-003",
+        prompt=question
+    )
+    answer_text = get_text_from_openai_answer(response)
+    assert answer_text == expect_answer