core/services/search.py

import asyncio
import json
import os

from opensearchpy import OpenSearch

from services.encoders import CustomJSONEncoder
from services.logger import root_logger as logger
from services.rediscache import redis

ELASTIC_HOST = os.environ.get('ELASTIC_HOST', '').replace('https://', '')
ELASTIC_USER = os.environ.get('ELASTIC_USER', '')
ELASTIC_PASSWORD = os.environ.get('ELASTIC_PASSWORD', '')
ELASTIC_PORT = os.environ.get('ELASTIC_PORT', 9200)
ELASTIC_AUTH = f'{ELASTIC_USER}:{ELASTIC_PASSWORD}' if ELASTIC_USER else ''
ELASTIC_URL = os.environ.get(
    'ELASTIC_URL', f'https://{ELASTIC_AUTH}@{ELASTIC_HOST}:{ELASTIC_PORT}'
)
REDIS_TTL = 86400  # 1 day in seconds

index_settings = {
    'settings': {
        'index': {'number_of_shards': 1, 'auto_expand_replicas': '0-all'},
        'analysis': {
            'analyzer': {
                'ru': {
                    'tokenizer': 'standard',
                    'filter': ['lowercase', 'ru_stop', 'ru_stemmer'],
                }
            },
            'filter': {
                'ru_stemmer': {'type': 'stemmer', 'language': 'russian'},
                'ru_stop': {'type': 'stop', 'stopwords': '_russian_'},
            },
        },
    },
    'mappings': {
        'properties': {
            'body': {'type': 'text', 'analyzer': 'ru'},
            'title': {'type': 'text', 'analyzer': 'ru'},
            'subtitle': {'type': 'text', 'analyzer': 'ru'},
            'lead': {'type': 'text', 'analyzer': 'ru'},
            # 'author': {'type': 'text'},
        }
    },
}

expected_mapping = index_settings['mappings']

# Create an event loop
search_loop = asyncio.get_event_loop()


class SearchService:
    def __init__(self, index_name='search_index'):
        self.index_name = index_name
        self.client = None
        self.lock = asyncio.Lock()  # Create an asyncio lock

        # Only initialize the instance if it's not already initialized
        if ELASTIC_HOST:
            try:
                self.client = OpenSearch(
                    hosts=[{'host': ELASTIC_HOST, 'port': ELASTIC_PORT}],
                    http_compress=True,
                    http_auth=(ELASTIC_USER, ELASTIC_PASSWORD),
                    use_ssl=True,
                    verify_certs=False,
                    ssl_assert_hostname=False,
                    ssl_show_warn=False,
                    # ca_certs = ca_certs_path
                )
                logger.info(' Клиент OpenSearch.org подключен')

                # Create a task and run it in the event loop
                search_loop.create_task(self.check_index())
            except Exception as exc:
                logger.error(f' {exc}')
                self.client = None

    def info(self):
        if isinstance(self.client, OpenSearch):
            logger.info(' Поиск подключен')  # : {self.client.info()}')
        else:
            logger.info(' * Задайте переменные среды для подключения к серверу поиска')

    def delete_index(self):
        if self.client:
            logger.debug(f' Удаляем индекс {self.index_name}')
            self.client.indices.delete(index=self.index_name, ignore_unavailable=True)

    def create_index(self):
        if self.client:
            logger.debug(f'Создается индекс: {self.index_name}')
            self.delete_index()
            self.client.indices.create(index=self.index_name, body=index_settings)
            logger.debug(f'Индекс {self.index_name} создан')

    async def check_index(self):
        if self.client:
            logger.debug(f' Проверяем индекс {self.index_name}...')
            if not self.client.indices.exists(index=self.index_name):
                self.create_index()
                self.client.indices.put_mapping(
                    index=self.index_name, body=expected_mapping
                )
            else:
                logger.info(f'найден существующий индекс {self.index_name}')
                # Check if the mapping is correct, and recreate the index if needed
                result = self.client.indices.get_mapping(index=self.index_name)
                if isinstance(result, str):
                    result = json.loads(result)
                if isinstance(result, dict):
                    mapping = result.get('mapping')
                    if mapping and mapping != expected_mapping:
                        logger.debug(f' найдена структура индексации: {mapping}')
                        logger.warn(
                            ' требуется другая структура индексации, переиндексация'
                        )
                        await self.recreate_index()

    async def recreate_index(self):
        if self.client:
            async with self.lock:
                self.client.indices.delete(index=self.index_name, ignore_unavailable=True)
                await self.check_index()

    def index(self, shout):
        if self.client:
            id_ = str(shout.id)
            logger.debug(f' Индексируем пост {id_}')
            asyncio.create_task(
                self.client.index(index=self.index_name, id=id_, body=shout.dict())
            )

    async def search(self, text, limit, offset):
        logger.debug(f' Ищем: {text}')
        search_body = {'query': {'match': {'_all': text}}}
        if self.client:
            search_response = self.client.search(
                index=self.index_name, body=search_body, size=limit, from_=offset
            )
            hits = search_response['hits']['hits']

            results = [{**hit['_source'], 'score': hit['_score']} for hit in hits]

            # Use Redis as cache with TTL
            redis_key = f'search:{text}'
            await redis.execute('SETEX', redis_key, REDIS_TTL, json.dumps(results, cls=CustomJSONEncoder))
        return []


search_service = SearchService()


async def search_text(text: str, limit: int = 50, offset: int = 0):
    payload = []
    if search_service.client:
        # Use OpenSearchService.search_post method
        payload = await search_service.search(text, limit, offset)
    return payload