refactor rewriting query (#69)

Signed-off-by: ChengZi <chen.zhang@zilliz.com>

src_towhee/pipelines/search/rewrite_query.py

@@ -8,33 +8,60 @@
 
 from utils import get_llm_op  # pylint: disable=C0413
 
+ZH_PRONOUN_LIST = ['他', '她', '它', '者', '这', ]
+
+EN_PRONOUN_LIST = ['he', 'his', 'him', 'she', 'her', 'it', 'they', 'them', 'their', 'both', 'former', 'latter',
+                   'this', 'these', 'that']
+
+PRONOUN_LIST = ZH_PRONOUN_LIST + EN_PRONOUN_LIST
+
+
+class RewriteQuery:
+    '''
+    Replace third-person pronouns with words from historical dialogue
+    '''
+
+    def __init__(self, config):
+        self._llm_op = get_llm_op(config)
+
+    def __call__(self, question: str, history: list = []):  # pylint: disable=W0102
+        if self._contain_pron(question):
+            prompt = self._build_prompt(question, history)
+            raw_ret = self._llm_op(prompt)
+            new_question = self._parse_raw_ret(raw_ret, question)
+            return new_question
+        else:
+            return question
+
+    def _contain_pron(self, question: str):
+        for pron in PRONOUN_LIST:
+            if pron in question.lower():
+                return True
+        return False
+
+    def _build_prompt(self, question: str, history: list = []):  # pylint: disable=W0102
+        output_str = ''
+        for qa in history:
+            output_str += f'Q: {qa[0]}\n'
+            output_str += f'A: {qa[1]}\n'
+        history_str = output_str.strip()
+        prompt = REWRITE_TEMP.format(question=question, history_str=history_str)
+        return [({'question': prompt})]
+
+    def _parse_raw_ret(self, raw_ret: str, question: str):
+        try:
+            raw_ret = raw_ret.replace('>', '>')
+            new_question = raw_ret.split('=> OUTPUT QUESTION: ')[1].split('-------------------')[0]
+        except:  # pylint: disable=W0702
+            new_question = question
+        return new_question
 
-def build_prompt(question: str, history: list = []):  # pylint: disable=W0102
-    if not history:
-        history_str = ''
-    output_str = ''
-    for qa in history:
-        output_str += f'Q: {qa[0]}\n'
-        output_str += f'A: {qa[1]}\n'
-    history_str = output_str.strip()
-    prompt = REWRITE_TEMP.format(question=question, history_str=history_str)
-    return [({'question': prompt})]
-
-def parse_raw_ret(raw_ret, question):
-    try:
-        new_question = raw_ret.split('=> OUTPUT QUESTION: ')[1]
-    except:  # pylint: disable=W0702
-        new_question = question
-    return new_question
 
 def custom_pipeline(config):
-    llm_op = get_llm_op(config)
     chat = AutoPipes.pipeline('osschat-search', config=config)
     p = (
         pipe.input('question', 'history', 'project')
-            .map(('question', 'history'), 'prompt', build_prompt)
-            .map('prompt', 'new_question', llm_op)
-            .map(('new_question', 'question'), 'new_question', parse_raw_ret)
+            .map(('question', 'history'), 'new_question', RewriteQuery(config))
             .map(('new_question', 'history', 'project'), 'answer', chat)
             .output('new_question', 'answer')
     )