Files
green_classroom/core/task_executor.py
2025-09-24 04:02:43 +08:00

250 lines
8.8 KiB
Python

"""
爬取任务执行器
负责执行爬取任务并更新任务状态
"""
import threading
import time
from django.utils import timezone
from django.db import transaction
from core.models import CrawlTask
from core.utils import crawl_by_keyword, crawl_historical_articles, full_site_crawler, WEBSITE_SEARCH_CONFIGS
class TaskExecutor:
"""任务执行器"""
def __init__(self):
self.running_tasks = {}
self.lock = threading.Lock()
def start_task(self, task_id):
"""启动任务"""
with self.lock:
if task_id in self.running_tasks:
return False, "任务已在运行中"
try:
task = CrawlTask.objects.get(id=task_id)
if task.status != 'pending':
return False, "任务状态不允许启动"
# 更新任务状态
task.status = 'running'
task.started_at = timezone.now()
task.save()
# 启动后台线程执行任务
thread = threading.Thread(target=self._execute_task, args=(task_id,))
thread.daemon = True
thread.start()
self.running_tasks[task_id] = thread
return True, "任务已启动"
except CrawlTask.DoesNotExist:
return False, "任务不存在"
except Exception as e:
return False, f"启动任务失败: {e}"
def cancel_task(self, task_id):
"""取消任务"""
with self.lock:
if task_id in self.running_tasks:
# 标记任务为取消状态
try:
task = CrawlTask.objects.get(id=task_id)
task.status = 'cancelled'
task.completed_at = timezone.now()
task.save()
# 移除运行中的任务
del self.running_tasks[task_id]
return True, "任务已取消"
except CrawlTask.DoesNotExist:
return False, "任务不存在"
else:
return False, "任务未在运行中"
def _execute_task(self, task_id):
"""执行任务的核心逻辑"""
try:
task = CrawlTask.objects.get(id=task_id)
# 根据任务类型执行不同的爬取逻辑
if task.task_type == 'keyword':
self._execute_keyword_task(task)
elif task.task_type == 'historical':
self._execute_historical_task(task)
elif task.task_type == 'full_site':
self._execute_full_site_task(task)
else:
raise ValueError(f"不支持的任务类型: {task.task_type}")
# 任务完成
with transaction.atomic():
task = CrawlTask.objects.select_for_update().get(id=task_id)
task.status = 'completed'
task.completed_at = timezone.now()
task.progress = 100
task.save()
except Exception as e:
# 任务失败
try:
with transaction.atomic():
task = CrawlTask.objects.select_for_update().get(id=task_id)
task.status = 'failed'
task.completed_at = timezone.now()
task.error_message = str(e)
task.save()
except:
pass
finally:
# 清理运行中的任务记录
with self.lock:
if task_id in self.running_tasks:
del self.running_tasks[task_id]
def _execute_keyword_task(self, task):
"""执行关键词搜索任务"""
# 更新当前操作
task.current_action = "开始关键词搜索"
task.save()
# 准备参数
selected_websites = task.websites.all()
if selected_websites:
websites = [w.name for w in selected_websites]
else:
websites = list(WEBSITE_SEARCH_CONFIGS.keys())
start_date = task.start_date.strftime('%Y-%m-%d') if task.start_date else None
end_date = task.end_date.strftime('%Y-%m-%d') if task.end_date else None
# 执行爬取
results = crawl_by_keyword(
keyword=task.keyword,
website_names=websites,
max_pages=task.max_pages,
start_date=start_date,
end_date=end_date,
max_articles=task.max_articles
)
# 更新结果
task.total_articles = results['total_articles']
task.success_count = results['success_count']
task.failed_count = results['failed_count']
task.result_details = results['website_results']
task.save()
def _execute_historical_task(self, task):
"""执行历史文章任务"""
# 更新当前操作
task.current_action = "开始历史文章爬取"
task.save()
# 准备参数
selected_websites = task.websites.all()
if selected_websites:
websites = [w.name for w in selected_websites]
else:
websites = list(WEBSITE_SEARCH_CONFIGS.keys())
start_date = task.start_date.strftime('%Y-%m-%d') if task.start_date else None
end_date = task.end_date.strftime('%Y-%m-%d') if task.end_date else None
# 执行爬取
results = crawl_historical_articles(
website_names=websites,
start_date=start_date,
end_date=end_date,
max_articles_per_site=task.max_articles
)
# 更新结果
task.total_articles = results['total_articles']
task.success_count = results['success_count']
task.failed_count = results['failed_count']
task.result_details = results['website_results']
task.save()
def _execute_full_site_task(self, task):
"""执行全站爬取任务"""
# 更新当前操作
task.current_action = "开始全站爬取"
task.save()
# 准备参数
selected_websites = task.websites.all()
if selected_websites:
websites = [w.name for w in selected_websites]
else:
websites = list(WEBSITE_SEARCH_CONFIGS.keys())
total_websites = len(websites)
completed_websites = 0
for website_name in websites:
try:
# 更新当前网站
task.current_website = website_name
task.current_action = f"正在爬取 {website_name}"
task.save()
# 获取或创建网站对象
from core.models import Website
website, created = Website.objects.get_or_create(
name=website_name,
defaults={
'base_url': WEBSITE_SEARCH_CONFIGS[website_name]["search_url"],
'enabled': True
}
)
# 执行全站爬取
full_site_crawler(
WEBSITE_SEARCH_CONFIGS[website_name]["search_url"],
website,
max_pages=task.max_pages
)
completed_websites += 1
progress = int((completed_websites / total_websites) * 100)
task.progress = progress
task.save()
except Exception as e:
# 记录错误但继续处理其他网站
print(f"爬取网站 {website_name} 时出错: {e}")
continue
# 更新最终结果
task.total_articles = completed_websites # 这里可以改为实际爬取的文章数
task.success_count = completed_websites
task.failed_count = total_websites - completed_websites
task.save()
def get_task_status(self, task_id):
"""获取任务状态"""
try:
task = CrawlTask.objects.get(id=task_id)
return {
'status': task.status,
'progress': task.progress,
'current_website': task.current_website,
'current_action': task.current_action,
'total_articles': task.total_articles,
'success_count': task.success_count,
'failed_count': task.failed_count,
'error_message': task.error_message
}
except CrawlTask.DoesNotExist:
return None
# 全局任务执行器实例
task_executor = TaskExecutor()