Use coversation template from fastchat for api proxy

Fix eventsource format

examples/server/api_like_OAI.py

@@ -1,14 +1,18 @@
 import argparse
 from flask import Flask, jsonify, request, Response
+from flask_cors import CORS
 import urllib.parse
 import requests
 import time
 import json
+from fastchat import conversation
 
 
 app = Flask(__name__)
+CORS(app)
 
 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", 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 +33,46 @@ def is_present(json, key):
     return True
 
 
+use_conversation_template = args.chat_prompt_model != ""
 
-#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_msg(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
 
@@ -69,8 +94,8 @@ 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"]
@@ -173,12 +198,12 @@ 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 +237,7 @@ 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__':