from flask_msearch import Search
[...]
search = Search()
search.init_app(app)

# models.py
class Post(db.Model):
    __tablename__ = 'post'
    __searchable__ = ['title', 'content']

# views.py
@app.route("/search")
def w_search():
    keyword = request.args.get('keyword')
    results = Post.query.msearch(keyword,fields=['title'],limit=20).filter(...)
    # or
    results = Post.query.filter(...).msearch(keyword,fields=['title'],limit=20).filter(...)
    # elasticsearch
    keyword = "title:book AND content:read"
    # more syntax please visit https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-query-string-query.html
    results = Post.query.msearch(keyword,limit=20).filter(...)
    return ''

# when backend is elasticsearch, MSEARCH_INDEX_NAME is unused
# flask-msearch will use table name as elasticsearch index name unless set __msearch_index__
MSEARCH_INDEX_NAME = 'msearch'
# simple,whoosh,elaticsearch, default is simple
MSEARCH_BACKEND = 'whoosh'
# table's primary key if you don't like to use id, or set __msearch_primary_key__ for special model
MSEARCH_PRIMARY_KEY = 'id'
# auto create or update index
MSEARCH_ENABLE = True
# logger level, default is logging.WARNING
MSEARCH_LOGGER = logging.DEBUG
# SQLALCHEMY_TRACK_MODIFICATIONS must be set to True when msearch auto index is enabled
SQLALCHEMY_TRACK_MODIFICATIONS = True
# when backend is elasticsearch
ELASTICSEARCH = {"hosts": ["127.0.0.1:9200"]}

from flask_msearch import Search
[...]
search = Search()
search.init_app(app)

class Post(db.Model):
    __tablename__ = 'basic_posts'
    __searchable__ = ['title', 'content']

    id = db.Column(db.Integer, primary_key=True)
    title = db.Column(db.String(49))
    content = db.Column(db.Text)

    def __repr__(self):
        return '<Post:{}>'.format(self.title)

db = SQLalchemy()
search = Search(db=db)

search.update_index()
search.update_index(Post)
# or
search.create_index(update=True)
search.create_index(Post, update=True)

search.delete_index()
search.delete_index(Post)
# or
search.create_index(delete=True)
search.create_index(Post, delete=True)

from jieba.analyse import ChineseAnalyzer
search = Search(analyzer=ChineseAnalyzer())

class Post(db.Model):
    __tablename__ = 'post'
    __searchable__ = ['title', 'content', 'tag.name']
    __msearch_analyzer__ = ChineseAnalyzer()

class Post(db.Model):
    __tablename__ = 'post'
    __searchable__ = ['title', 'content', 'tag.name']
    __msearch_index__ = "post111"

from whoosh.fields import ID

class Post(db.Model):
    __tablename__ = 'post'
    __searchable__ = ['title', 'content', 'tag.name']
    __msearch_schema__ = {'title': ID(stored=True, unique=True), 'content': 'text'}

from whoosh.qparser import MultifieldParser

class Post(db.Model):
    __tablename__ = 'post'
    __searchable__ = ['title', 'content']

    def _parser(fieldnames, schema, group, **kwargs):
        return MultifieldParser(fieldnames, schema, group=group, **kwargs)

    __msearch_parser__ = _parser

# app.py
app.config["MSEARCH_INDEX_SIGNAL"] = celery_signal
# or use string as variable
app.config["MSEARCH_INDEX_SIGNAL"] = "modulename.tasks.celery_signal"
search = Search(app)

# tasks.py
from flask_msearch.signal import default_signal

@celery.task(bind=True)
def celery_signal_task(self, backend, sender, changes):
    default_signal(backend, sender, changes)
    return str(self.request.id)

def celery_signal(backend, sender, changes):
    return celery_signal_task.delay(backend, sender, changes)

class Tag(db.Model):
    __tablename__ = 'tag'

    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(49))

class Post(db.Model):
    __tablename__ = 'post'
    __searchable__ = ['title', 'content', 'tag.name']

    id = db.Column(db.Integer, primary_key=True)
    title = db.Column(db.String(49))
    content = db.Column(db.Text)

    # one to one
    tag_id = db.Column(db.Integer, db.ForeignKey('tag.id'))
    tag = db.relationship(
        Tag, backref=db.backref(
            'post', uselist=False), uselist=False)

    def __repr__(self):
        return '<Post:{}>'.format(self.title)

class Tag....
  ......
  def msearch_post_tag(self, delete=False):
      from sqlalchemy import text
      sql = text('select id from post where tag_id=' + str(self.id))
      return {
          'attrs': [{
              'id': str(i[0]),
              'tag.name': self.name
          } for i in db.engine.execute(sql)],
          '_index': Post
      }