Use conversation template for api proxy, fix eventsource format

examples/server/README.md

@@ -195,6 +195,14 @@ bash chat.sh
 API example using Python Flask: [api_like_OAI.py](api_like_OAI.py)
 This example must be used with server.cpp
 
+requirements:
+
+```shell
+pip install flask flask-cors fschat  # flask-cors and fschat are optional. flask-cors is used to allow cross-origin requests, fschat is used for integration of chat template
+```
+
+Run the server:
+
 ```sh
 python api_like_OAI.py
 ```
@@ -204,6 +212,8 @@ After running the API server, you can use it in Python by setting the API base U
 openai.api_base = "http://<Your api-server IP>:port"
 ```
 
+For better integration with the model, it is recommended to utilize the `--chat-prompt-model` parameter when starting up the system, rather than relying solely on parameters like `--user-name`. This specific parameter accepts model names that have been registered within the [FastChat/conversation.py](https://github.com/lm-sys/FastChat/blob/main/fastchat/conversation.py) file, an example would be `llama-2`.
+
 Then you can utilize llama.cpp as an OpenAI's **chat.completion** or **text_completion** API
 
 ### Extending or building alternative Web Front End

examples/server/api_like_OAI.py

@@ -4,11 +4,20 @@
 import requests
 import time
 import json
-
+try:
+    from fastchat import conversation
+except ImportError:
+    conversation = None
 
 app = Flask(__name__)
+try:
+    from flask_cors import CORS
+    CORS(app)
+except ImportError:
+    pass
 
 parser = argparse.ArgumentParser(description="An example of using server.cpp with a similar API to OAI. It must be used together with server.cpp.")
+parser.add_argument("--chat-prompt-model", type=str, help="Set the model name of conversation template", default="")
 parser.add_argument("--chat-prompt", type=str, help="the top prompt in chat completions(default: 'A chat between a curious user and an artificial intelligence assistant. The assistant follows the given rules no matter what.\\n')", default='A chat between a curious user and an artificial intelligence assistant. The assistant follows the given rules no matter what.\\n')
 parser.add_argument("--user-name", type=str, help="USER name in chat completions(default: '\\nUSER: ')", default="\\nUSER: ")
 parser.add_argument("--ai-name", type=str, help="ASSISTANT name in chat completions(default: '\\nASSISTANT: ')", default="\\nASSISTANT: ")
@@ -29,25 +38,46 @@ def is_present(json, key):
     return True
 
 
+use_conversation_template = args.chat_prompt_model != "" and conversation is not None
 
-#convert chat to prompt
-def convert_chat(messages):
-    prompt = "" + args.chat_prompt.replace("\\n", "\n")
-
-    system_n = args.system_name.replace("\\n", "\n")
-    user_n = args.user_name.replace("\\n", "\n")
-    ai_n = args.ai_name.replace("\\n", "\n")
-    stop = args.stop.replace("\\n", "\n")
+if use_conversation_template:
+    conv = conversation.get_conv_template(args.chat_prompt_model)
+    stop_token = conv.stop_str
+else:
+    stop_token = args.stop
 
 
-    for line in messages:
-        if (line["role"] == "system"):
-            prompt += f"{system_n}{line['content']}"
-        if (line["role"] == "user"):
-            prompt += f"{user_n}{line['content']}"
-        if (line["role"] == "assistant"):
-            prompt += f"{ai_n}{line['content']}{stop}"
-    prompt += ai_n.rstrip()
+#convert chat to prompt
+def convert_chat(messages):
+    if use_conversation_template:
+        conv = conversation.get_conv_template(args.chat_prompt_model)
+        for line in messages:
+            if (line["role"] == "system"):
+                try:
+                    conv.set_system_message(line["content"])
+                except Exception:
+                    pass
+            elif (line["role"] == "user"):
+                conv.append_message(conv.roles[0], line["content"])
+            elif (line["role"] == "assistant"):
+                conv.append_message(conv.roles[1], line["content"])
+        conv.append_message(conv.roles[1], None)
+        prompt = conv.get_prompt()
+    else:
+        prompt = "" + args.chat_prompt.replace("\\n", "\n")
+        system_n = args.system_name.replace("\\n", "\n")
+        user_n = args.user_name.replace("\\n", "\n")
+        ai_n = args.ai_name.replace("\\n", "\n")
+        stop = stop_token.replace("\\n", "\n")
+
+        for line in messages:
+            if (line["role"] == "system"):
+                prompt += f"{system_n}{line['content']}"
+            if (line["role"] == "user"):
+                prompt += f"{user_n}{line['content']}"
+            if (line["role"] == "assistant"):
+                prompt += f"{ai_n}{line['content']}{stop}"
+        prompt += ai_n.rstrip()
 
     return prompt
 
@@ -69,11 +99,11 @@ def make_postData(body, chat=False, stream=False):
     if(is_present(body, "mirostat_eta")): postData["mirostat_eta"] = body["mirostat_eta"]
     if(is_present(body, "seed")): postData["seed"] = body["seed"]
     if(is_present(body, "logit_bias")): postData["logit_bias"] = [[int(token), body["logit_bias"][token]] for token in body["logit_bias"].keys()]
-    if (args.stop != ""):
-        postData["stop"] = [args.stop]
+    if stop_token:  # "" or None
+        postData["stop"] = [stop_token]
     else:
         postData["stop"] = []
-    if(is_present(body, "stop")): postData["stop"] += body["stop"]
+    if(is_present(body, "stop")): postData["stop"] += body["stop"] or []
     postData["n_keep"] = -1
     postData["stream"] = stream
 
@@ -173,12 +203,12 @@ def generate():
             data = requests.request("POST", urllib.parse.urljoin(args.llama_api, "/completion"), data=json.dumps(postData), stream=True)
             time_now = int(time.time())
             resData = make_resData_stream({}, chat=True, time_now=time_now, start=True)
-            yield 'data: {}\n'.format(json.dumps(resData))
+            yield 'data: {}\n\n'.format(json.dumps(resData))
             for line in data.iter_lines():
                 if line:
                     decoded_line = line.decode('utf-8')
                     resData = make_resData_stream(json.loads(decoded_line[6:]), chat=True, time_now=time_now)
-                    yield 'data: {}\n'.format(json.dumps(resData))
+                    yield 'data: {}\n\n'.format(json.dumps(resData))
         return Response(generate(), mimetype='text/event-stream')
 
 
@@ -212,7 +242,7 @@ def generate():
                 if line:
                     decoded_line = line.decode('utf-8')
                     resData = make_resData_stream(json.loads(decoded_line[6:]), chat=False, time_now=time_now)
-                    yield 'data: {}\n'.format(json.dumps(resData))
+                    yield 'data: {}\n\n'.format(json.dumps(resData))
         return Response(generate(), mimetype='text/event-stream')
 
 if __name__ == '__main__':