core/services/search.py

import json
import logging
import os

from elasticsearch import Elasticsearch

from services.rediscache import redis


logger = logging.getLogger('[services.search] ')
logger.setLevel(logging.DEBUG)

ELASTIC_HOST = os.environ.get('ELASTIC_HOST', 'localhost').replace('https://', '').replace('http://', '')
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}')
ELASTIC_REINDEX = os.environ.get('ELASTIC_REINDEX', '')
REDIS_TTL = 86400  # 1 day in seconds


class SearchService:
    async def __init__(self, index_name='search_index'):
        logging.info('Initializing SearchService')
        self.index_name = index_name
        self.elasticsearch_client = Elasticsearch(f'{ELASTIC_URL}', verify_certs=False)
        self.check_index()

        if ELASTIC_REINDEX:
            self.recreate_index()

    def info(self):
        logging.info(f'Initializing SearchService {self.elasticsearch_client}')

    def delete_index(self):
        self.elasticsearch_client.indices.delete(index=self.index_name, ignore_unavailable=True)

    def create_index(self):
        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'},
                    'text': {'type': 'text'},
                    'author': {'type': 'text'},
                }
            },
        }

        self.elasticsearch_client.indices.create(index=self.index_name, body=index_settings)
        self.elasticsearch_client.indices.close(index=self.index_name)
        self.elasticsearch_client.indices.open(index=self.index_name)

    def put_mapping(self):
        mapping = {
            'properties': {
                'body': {'type': 'text', 'analyzer': 'ru'},
                'text': {'type': 'text'},
                'author': {'type': 'text'},
            }
        }

        self.elasticsearch_client.indices.put_mapping(index=self.index_name, body=mapping)

    def check_index(self):
        if not self.elasticsearch_client.indices.exists(index=self.index_name):
            logger.debug(f'Creating {self.index_name} index')
            self.create_index()
            self.put_mapping()

    def recreate_index(self):
        self.delete_index()
        self.check_index()

    def index_post(self, shout):
        id_ = str(shout.id)
        logger.debug(f'Indexing post id {id_}')
        self.elasticsearch_client.index(index=self.index_name, id=id_, body=shout)

    def search_post(self, query, limit, offset):
        logger.debug(f'query: {query}')
        search_body = {
            'query': {'match': {'_all': query}},
        }

        search_response = self.elasticsearch_client.search(
            index=self.index_name, body=search_body, size=limit, from_=offset
        )
        hits = search_response['hits']['hits']

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


search = SearchService()


async def search_text(text: str, limit: int = 50, offset: int = 0):
    payload = []
    try:
        # Use a key with a prefix to differentiate search results from other Redis data
        redis_key = f'search:{text}'
        # Use OpenSearchService.search_post method
        payload = search.search_post(text, limit, offset)
        # Use Redis as cache with TTL
        await redis.execute('SETEX', redis_key, REDIS_TTL, json.dumps(payload))
    except Exception as e:
        logging.error(f'Error during search: {e}')
    return payload