python异步操作sqlite3

桃扇骨 2022-02-05 12:27 510阅读 0赞

# Define your item pipelines here #

#  #

from scrapy import log
    from twisted.enterprise import adbapi
    import MySQLdb.cursors
    import time
    import sqlite3

# Database storage pipeline. Adapted from Scrapy docs #

# Connects to a MySQL database via a connection pool to allow #

# for non blocking DB access #

class DbPipeline(object):
        def __init__(self):
            self.dbpool = adbapi.ConnectionPool('MySQLdb',
                    host='storo',
                    db='ritesh',
                    user='ritesh',
                    passwd='6510',
                    cursorclass=MySQLdb.cursors.DictCursor,
                    charset='utf8',
                    use_unicode=True
                    )
    
        def process_item(self,item,spider):
            query = self.dbpool.runInteraction(self.__insertdata, item, spider.name)
            query.addErrback(self.handle_error)
            return item
    
        def __insertdata(self, tx, item, spidername):
            for img in item['images']:
                log.msg(type(img['url']))
                tx.execute("select * from data where url = %s", (img['url']))
                result = tx.fetchone()
                if result:
                    log.msg("Item has been stored previously", level=log.DEBUG)
                else:
                    tx.execute(\
                            "insert into data(url, localpath, checksum, created, spidername)"
                            "values (%s, %s, %s, %s, %s)",
                            (img['url'],
                             img['path'],
                             img['checksum'],
                             time.time(),
                             spidername)
                            )
                    log.msg("Item stored in db", level=log.DEBUG)
    
        def handle_error(self, e):
            log.err(e)
    class DbSqlitePipeline(object):
        def __init__(self):
            """Initialize"""
            self.__dbpool = adbapi.ConnectionPool('sqlite3',
                    database='/users/mscit/1006510k/scraper/db/sqlite.db',
                    check_same_thread=False)
        def shutdown(self):
            """Shutdown the connection pool"""
            self.__dbpool.close()
        def process_item(self,item,spider):
            """Process each item process_item"""
            query = self.__dbpool.runInteraction(self.__insertdata, item, spider)
            query.addErrback(self.handle_error)
            return item
        def __insertdata(self,tx,item,spider):
            """Insert data into the sqlite3 database"""
            spidername=spider.name
            for img in item['images']:
                tx.execute("select * from data where url = ?", (img['url'],))
                result = tx.fetchone()
                if result:
                    log.msg("Already exists in database", level=log.DEBUG)
                else:
                    tx.execute(\
                            "insert into data(url, localpath, checksum, created, spidername) values (?,?,?,?,?)",(
                                img['url'],
                                img['path'],
                                img['checksum'],
                                time.time(),
                                spidername)
                            )
                    log.msg("Item stored in db", level=log.DEBUG)
    def handle_error(self,e):
        log.err(e)