# -*- coding: utf-8 -*-

"""

Created on 2018-06-19 17:17

---------

@summary: item 管理器， 负责缓冲添加到数据库中的item， 由该manager统一添加。防止多线程同时访问数据库

---------

@author: Boris

@email: boris_liu@foxmail.com

"""

import threading

from queue import Queue

import feapder.utils.tools as tools

from feapder import setting

from feapder.db.redisdb import RedisDB

from feapder.dedup import Dedup

from feapder.network.item import Item, UpdateItem

from feapder.pipelines import BasePipeline

from feapder.pipelines.mysql_pipeline import MysqlPipeline

from feapder.utils import metrics

from feapder.utils.log import log

MYSQL_PIPELINE_PATH = "feapder.pipelines.mysql_pipeline.MysqlPipeline"

class ItemBuffer(threading.Thread):

dedup = None

__redis_db = None

def __init__(self, redis_key, task_table=None):

if not hasattr(self, "_table_item"):

super(ItemBuffer, self).__init__()

self._thread_stop = False

self._is_adding_to_db = False

self._redis_key = redis_key

self._task_table = task_table

self._items_queue = Queue(maxsize=setting.ITEM_MAX_CACHED_COUNT)

self._table_request = setting.TAB_REQUESTS.format(redis_key=redis_key)

self._table_failed_items = setting.TAB_FAILED_ITEMS.format(

redis_key=redis_key

)

self._item_tables = {

# 'item_name': 'table_name' # 缓存item名与表名对应关系

}

self._item_update_keys = {

# 'table_name': ['id', 'name'...] # 缓存table_name与__update_key__的关系

}

self._pipelines = self.load_pipelines()

self._have_mysql_pipeline = MYSQL_PIPELINE_PATH in setting.ITEM_PIPELINES

self._mysql_pipeline = None

if setting.ITEM_FILTER_ENABLE and not self.__class__.dedup:

if setting.ITEM_FILTER_SETTING.get(

"filter_type"

) == Dedup.BloomFilter or setting.ITEM_FILTER_SETTING.get("name"):

self.__class__.dedup = Dedup(

to_md5=False, **setting.ITEM_FILTER_SETTING

)

else:

self.__class__.dedup = Dedup(

to_md5=False,

name=self._redis_key,

**setting.ITEM_FILTER_SETTING,

)

# 导出重试的次数

self.export_retry_times = 0

# 导出失败的次数 TODO 非air爬虫使用redis统计

self.export_falied_times = 0

@property

def redis_db(self):

if self.__class__.__redis_db is None:

self.__class__.__redis_db = RedisDB()

return self.__class__.__redis_db

def load_pipelines(self):

pipelines = []

for pipeline_path in setting.ITEM_PIPELINES:

pipeline = tools.import_cls(pipeline_path)()

if not isinstance(pipeline, BasePipeline):

raise ValueError(f"{pipeline_path} 需继承 feapder.pipelines.BasePipeline")

pipelines.append(pipeline)

return pipelines

@property

def mysql_pipeline(self):

if not self._mysql_pipeline:

self._mysql_pipeline = tools.import_cls(MYSQL_PIPELINE_PATH)()

return self._mysql_pipeline

def run(self):

self._thread_stop = False

while not self._thread_stop:

self.flush()

tools.delay_time(setting.ITEM_UPLOAD_INTERVAL)

self.close()

def stop(self):

self._thread_stop = True

self._started.clear()

def put_item(self, item):

if isinstance(item, Item):

# 入库前的回调

item.pre_to_db()

self._items_queue.put(item)

def flush(self):

try:

items = []

update_items = []

requests = []

callbacks = []

items_fingerprints = []

data_count = 0

while not self._items_queue.empty():

data = self._items_queue.get_nowait()

data_count += 1

# data 分类

if callable(data):

callbacks.append(data)

elif isinstance(data, UpdateItem):

update_items.append(data)

elif isinstance(data, Item):

items.append(data)

if setting.ITEM_FILTER_ENABLE:

items_fingerprints.append(data.fingerprint)

else: # request-redis

requests.append(data)

if data_count >= setting.ITEM_UPLOAD_BATCH_MAX_SIZE:

self.__add_item_to_db(

items, update_items, requests, callbacks, items_fingerprints

)

items = []

update_items = []

requests = []

callbacks = []

items_fingerprints = []

data_count = 0

if data_count:

self.__add_item_to_db(

items, update_items, requests, callbacks, items_fingerprints

)

except Exception as e:

log.exception(e)

def get_items_count(self):

return self._items_queue.qsize()

def is_adding_to_db(self):

return self._is_adding_to_db

def __dedup_items(self, items, items_fingerprints):

"""

去重

@param items:

@param items_fingerprints:

@return: 返回去重后的items, items_fingerprints

"""

if not items:

return items, items_fingerprints

is_exists = self.__class__.dedup.get(items_fingerprints)

is_exists = is_exists if isinstance(is_exists, list) else [is_exists]

dedup_items = []

dedup_items_fingerprints = []

items_count = dedup_items_count = dup_items_count = 0

while is_exists:

item = items.pop(0)

items_fingerprint = items_fingerprints.pop(0)

is_exist = is_exists.pop(0)

items_count += 1

if not is_exist:

dedup_items.append(item)

dedup_items_fingerprints.append(items_fingerprint)

dedup_items_count += 1

else:

dup_items_count += 1

log.info(

"待入库数据 {} 条， 重复 {} 条，实际待入库数据 {} 条".format(

items_count, dup_items_count, dedup_items_count

)

)

return dedup_items, dedup_items_fingerprints

def __pick_items(self, items, is_update_item=False):

"""

将每个表之间的数据分开 拆分后 原items为空

@param items:

@param is_update_item:

@return:

"""

datas_dict = {

# 'table_name': [{}, {}]

}

while items:

item = items.pop(0)

# 取item下划线格式的名

# 下划线类的名先从dict中取，没有则现取，然后存入dict。加快下次取的速度

item_name = item.item_name

table_name = self._item_tables.get(item_name)

if not table_name:

table_name = item.table_name

self._item_tables[item_name] = table_name

if table_name not in datas_dict:

datas_dict[table_name] = []

datas_dict[table_name].append(item.to_dict)

if is_update_item and table_name not in self._item_update_keys:

self._item_update_keys[table_name] = item.update_key

return datas_dict

def __export_to_db(self, table, datas, is_update=False, update_keys=()):

for pipeline in self._pipelines:

if is_update:

if table == self._task_table and not isinstance(

pipeline, MysqlPipeline

):

continue

if not pipeline.update_items(table, datas, update_keys=update_keys):

log.error(

f"{pipeline.__class__.__name__} 更新数据失败. table: {table} items: {datas}"

)

return False

else:

if not pipeline.save_items(table, datas):

log.error(

f"{pipeline.__class__.__name__} 保存数据失败. table: {table} items: {datas}"

)

return False

# 若是任务表, 且上面的pipeline里没mysql，则需调用mysql更新任务

if not self._have_mysql_pipeline and is_update and table == self._task_table:

if not self.mysql_pipeline.update_items(

table, datas, update_keys=update_keys

):

log.error(

f"{self.mysql_pipeline.__class__.__name__} 更新数据失败. table: {table} items: {datas}"

)

return False

self.metric_datas(table=table, datas=datas)

return True

def __add_item_to_db(

self, items, update_items, requests, callbacks, items_fingerprints

):

export_success = True

self._is_adding_to_db = True

# 去重

if setting.ITEM_FILTER_ENABLE:

items, items_fingerprints = self.__dedup_items(items, items_fingerprints)

# 分捡

items_dict = self.__pick_items(items)

update_items_dict = self.__pick_items(update_items, is_update_item=True)

# item批量入库

failed_items = {"add": [], "update": [], "requests": []}

while items_dict:

table, datas = items_dict.popitem()

log.debug(

"""

-------------- item 批量入库 --------------

表名: %s

datas: %s

"""

% (table, tools.dumps_json(datas, indent=16))

)

if not self.__export_to_db(table, datas):

export_success = False

failed_items["add"].append({"table": table, "datas": datas})

# 执行批量update

while update_items_dict:

table, datas = update_items_dict.popitem()

log.debug(

"""

-------------- item 批量更新 --------------

表名: %s

datas: %s

"""

% (table, tools.dumps_json(datas, indent=16))

)

update_keys = self._item_update_keys.get(table)

if not self.__export_to_db(

table, datas, is_update=True, update_keys=update_keys

):

export_success = False

failed_items["update"].append(

{"table": table, "datas": datas, "update_keys": update_keys}

)

if export_success:

# 执行回调

while callbacks:

try:

callback = callbacks.pop(0)

callback()

except Exception as e:

log.exception(e)

# 删除做过的request

if requests:

self.redis_db.zrem(self._table_request, requests)

# 去重入库

if setting.ITEM_FILTER_ENABLE:

if items_fingerprints:

self.__class__.dedup.add(items_fingerprints, skip_check=True)

else:

failed_items["requests"] = requests

if self.export_retry_times > setting.EXPORT_DATA_MAX_RETRY_TIMES:

if self._redis_key != "air_spider":

# 失败的item记录到redis

self.redis_db.sadd(self._table_failed_items, failed_items)

# 删除做过的request

if requests:

self.redis_db.zrem(self._table_request, requests)

log.error(

"入库超过最大重试次数，不再重试，数据记录到redis，items:\n {}".format(

tools.dumps_json(failed_items)

)

)

self.export_retry_times = 0

else:

tip = ["入库不成功"]

if callbacks:

tip.append("不执行回调")

if requests:

tip.append("不删除任务")

exists = self.redis_db.zexists(self._table_request, requests)

for exist, request in zip(exists, requests):

if exist:

self.redis_db.zadd(self._table_request, requests, 300)

if setting.ITEM_FILTER_ENABLE:

tip.append("数据不入去重库")

if self._redis_key != "air_spider":

tip.append("将自动重试")

tip.append("失败items:\n {}".format(tools.dumps_json(failed_items)))

log.error("，".join(tip))

self.export_falied_times += 1

if self._redis_key != "air_spider":

self.export_retry_times += 1

if self.export_falied_times > setting.EXPORT_DATA_MAX_FAILED_TIMES:

# 报警

msg = "《{}》爬虫导出数据失败，失败次数：{}，请检查爬虫是否正常".format(

self._redis_key, self.export_falied_times

)

log.error(msg)

tools.send_msg(

msg=msg,

level="error",

message_prefix="《%s》爬虫导出数据失败" % (self._redis_key),

)

self._is_adding_to_db = False

def metric_datas(self, table, datas):

"""

打点 记录总条数及每个key情况

@param table: 表名

@param datas: 数据 列表

@return:

"""

total_count = 0

for data in datas:

total_count += 1

for k, v in data.items():

metrics.emit_counter(k, int(bool(v)), classify=table)

metrics.emit_counter("total count", total_count, classify=table)

def close(self):

# 调用pipeline的close方法

for pipeline in self._pipelines:

try:

pipeline.close()

except:

pass