ragflow/rag/nlp/query.py

#
#  Copyright 2024 The InfiniFlow Authors. All Rights Reserved.
#
#  Licensed under the Apache License, Version 2.0 (the "License");
#  you may not use this file except in compliance with the License.
#  You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
#  Unless required by applicable law or agreed to in writing, software
#  distributed under the License is distributed on an "AS IS" BASIS,
#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#  See the License for the specific language governing permissions and
#  limitations under the License.
#

import logging
import json
import re
from rag.utils.doc_store_conn import MatchTextExpr

from rag.nlp import rag_tokenizer, term_weight, synonym


class FulltextQueryer:
    def __init__(self):
        self.tw = term_weight.Dealer()
        self.syn = synonym.Dealer()
        self.query_fields = [
            "title_tks^10",
            "title_sm_tks^5",
            "important_kwd^30",
            "important_tks^20",
            "content_ltks^2",
            "content_sm_ltks",
        ]

    @staticmethod
    def subSpecialChar(line):
        return re.sub(r"([:\{\}/\[\]\-\*\"\(\)\|\+~\^])", r"\\\1", line).strip()

    @staticmethod
    def isChinese(line):
        arr = re.split(r"[ \t]+", line)
        if len(arr) <= 3:
            return True
        e = 0
        for t in arr:
            if not re.match(r"[a-zA-Z]+$", t):
                e += 1
        return e * 1.0 / len(arr) >= 0.7

    @staticmethod
    def rmWWW(txt):
        patts = [
            (
                r"是*(什么样的|哪家|一下|那家|请问|啥样|咋样了|什么时候|何时|何地|何人|是否|是不是|多少|哪里|怎么|哪儿|怎么样|如何|哪些|是啥|啥是|啊|吗|呢|吧|咋|什么|有没有|呀|谁|哪位|哪个)是*",
                "",
            ),
            (r"(^| )(what|who|how|which|where|why)('re|'s)? ", " "),
            (r"(^| )('s|'re|is|are|were|was|do|does|did|don't|doesn't|didn't|has|have|be|there|you|me|your|my|mine|just|please|may|i|should|would|wouldn't|will|won't|done|go|for|with|so|the|a|an|by|i'm|it's|he's|she's|they|they're|you're|as|by|on|in|at|up|out|down|of) ", " ")
        ]
        for r, p in patts:
            txt = re.sub(r, p, txt, flags=re.IGNORECASE)
        return txt

    def question(self, txt, tbl="qa", min_match:float=0.6):
        txt = re.sub(
            r"[ :\r\n\t,，。？?/`!！&\^%%()^\[\]]+",
            " ",
            rag_tokenizer.tradi2simp(rag_tokenizer.strQ2B(txt.lower())),
        ).strip()
        txt = FulltextQueryer.rmWWW(txt)

        if not self.isChinese(txt):
            txt = FulltextQueryer.rmWWW(txt)
            tks = rag_tokenizer.tokenize(txt).split()
            keywords = [t for t in tks if t]
            tks_w = self.tw.weights(tks, preprocess=False)
            tks_w = [(re.sub(r"[ \\\"'^]", "", tk), w) for tk, w in tks_w]
            tks_w = [(re.sub(r"^[a-z0-9]$", "", tk), w) for tk, w in tks_w if tk]
            tks_w = [(re.sub(r"^[\+-]", "", tk), w) for tk, w in tks_w if tk]
            syns = []
            for tk, w in tks_w:
                syn = self.syn.lookup(tk)
                syn = rag_tokenizer.tokenize(" ".join(syn)).split()
                keywords.extend(syn)
                syn = ["\"{}\"^{:.4f}".format(s, w / 4.) for s in syn]
                syns.append(" ".join(syn))

            q = ["({}^{:.4f}".format(tk, w) + " {})".format(syn) for (tk, w), syn in zip(tks_w, syns) if tk]
            for i in range(1, len(tks_w)):
                q.append(
                    '"%s %s"^%.4f'
                    % (
                        tks_w[i - 1][0],
                        tks_w[i][0],
                        max(tks_w[i - 1][1], tks_w[i][1]) * 2,
                    )
                )
            if not q:
                q.append(txt)
            query = " ".join(q)
            return MatchTextExpr(
                self.query_fields, query, 100
            ), keywords

        def need_fine_grained_tokenize(tk):
            if len(tk) < 3:
                return False
            if re.match(r"[0-9a-z\.\+#_\*-]+$", tk):
                return False
            return True

        txt = FulltextQueryer.rmWWW(txt)
        qs, keywords = [], []
        for tt in self.tw.split(txt)[:256]:  # .split():
            if not tt:
                continue
            keywords.append(tt)
            twts = self.tw.weights([tt])
            syns = self.syn.lookup(tt)
            if syns: keywords.extend(syns)
            logging.debug(json.dumps(twts, ensure_ascii=False))
            tms = []
            for tk, w in sorted(twts, key=lambda x: x[1] * -1):
                sm = (
                    rag_tokenizer.fine_grained_tokenize(tk).split()
                    if need_fine_grained_tokenize(tk)
                    else []
                )
                sm = [
                    re.sub(
                        r"[ ,\./;'\[\]\\`~!@#$%\^&\*\(\)=\+_<>\?:\"\{\}\|，。；‘’【】、！￥……（）——《》？：“”-]+",
                        "",
                        m,
                    )
                    for m in sm
                ]
                sm = [FulltextQueryer.subSpecialChar(m) for m in sm if len(m) > 1]
                sm = [m for m in sm if len(m) > 1]

                keywords.append(re.sub(r"[ \\\"']+", "", tk))
                keywords.extend(sm)
                if len(keywords) >= 12:
                    break

                tk_syns = self.syn.lookup(tk)
                tk = FulltextQueryer.subSpecialChar(tk)
                if tk.find(" ") > 0:
                    tk = '"%s"' % tk
                if tk_syns:
                    tk = f"({tk} %s)" % " ".join(tk_syns)
                if sm:
                    tk = f'{tk} OR "%s" OR ("%s"~2)^0.5' % (" ".join(sm), " ".join(sm))
                if tk.strip():
                    tms.append((tk, w))

            tms = " ".join([f"({t})^{w}" for t, w in tms])

            if len(twts) > 1:
                tms += ' ("%s"~4)^1.5' % (" ".join([t for t, _ in twts]))
            if re.match(r"[0-9a-z ]+$", tt):
                tms = f'("{tt}" OR "%s")' % rag_tokenizer.tokenize(tt)

            syns = " OR ".join(
                [
                    '"%s"^0.7'
                    % FulltextQueryer.subSpecialChar(rag_tokenizer.tokenize(s))
                    for s in syns
                ]
            )
            if syns:
                tms = f"({tms})^5 OR ({syns})^0.7"

            qs.append(tms)

        if qs:
            query = " OR ".join([f"({t})" for t in qs if t])
            return MatchTextExpr(
                self.query_fields, query, 100, {"minimum_should_match": min_match}
            ), keywords
        return None, keywords

    def hybrid_similarity(self, avec, bvecs, atks, btkss, tkweight=0.3, vtweight=0.7):
        from sklearn.metrics.pairwise import cosine_similarity as CosineSimilarity
        import numpy as np

        sims = CosineSimilarity([avec], bvecs)
        tksim = self.token_similarity(atks, btkss)
        return np.array(sims[0]) * vtweight + np.array(tksim) * tkweight, tksim, sims[0]

    def token_similarity(self, atks, btkss):
        def toDict(tks):
            d = {}
            if isinstance(tks, str):
                tks = tks.split()
            for t, c in self.tw.weights(tks, preprocess=False):
                if t not in d:
                    d[t] = 0
                d[t] += c
            return d

        atks = toDict(atks)
        btkss = [toDict(tks) for tks in btkss]
        return [self.similarity(atks, btks) for btks in btkss]

    def similarity(self, qtwt, dtwt):
        if isinstance(dtwt, type("")):
            dtwt = {t: w for t, w in self.tw.weights(self.tw.split(dtwt), preprocess=False)}
        if isinstance(qtwt, type("")):
            qtwt = {t: w for t, w in self.tw.weights(self.tw.split(qtwt), preprocess=False)}
        s = 1e-9
        for k, v in qtwt.items():
            if k in dtwt:
                s += v  # * dtwt[k]
        q = 1e-9
        for k, v in qtwt.items():
            q += v
        return s / q