为什么此 try/except 循环因错误而退出？

Question

我有一个收集 Reddit 评论的脚本。它从一个包含 link 列表的 csv 文件中提取。一些 links 已经死了，我得到 404/403/etc 错误。下面的代码将正确识别它们并跳过，但它随后退出循环并完成制作 csv 文件的过程而不继续下一个 link.

import praw
import pprint
import csv
import os
import pandas as pd
from collections import namedtuple
from datetime import datetime
from pathlib import Path

def scrape_comments(reddit_api, csv_file, dest):
    df = pd.read_csv(csv_file)
    data = []
    try:
        for pid in df.id:
            # post_comment = []
            submission = reddit_api.submission(id=pid)
            submission.comments.replace_more(limit=None)
            for comment in submission.comments.list():
                # post_comment.append(comment.body)
                data.append((pid, comment.id, comment.parent_id, comment.body, comment.link_id,comment.author, comment.score, comment.created_utc, comment.subreddit))
            # data.append((pid, ";".join(post_comment)))
    except:
        print ("Error! Skip the Current subreddit")
    df = pd.DataFrame(data, columns=["post_id", "comment_id", "comment_parent_id", "comment_body", "comment_link_id","comment_author", "comment_score","comment_created","comment_subreddit"]) # append tuple
    df.to_csv(dest, index=False, encoding='utf-8')

if __name__ == "__main__":
    reddit_api = praw.Reddit(
        client_id="####",
        client_secret="####",
        user_agent="####",
        username="####",
        password="####"
    )
    # reddit_api = init_praw(client_id, client_secret, user_agent, username, password)
    csv_file = "####"
    dest_dir = "####"
    dest_name = "reddits_comments.csv"
    Path(dest_dir).mkdir(parents=True, exist_ok=True)
    dest = os.path.join(dest_dir, dest_name)
    scrape_comments(reddit_api, csv_file, dest)

Answer 1

您应该将 try/except 放在代码的一小部分周围，如评论中所述。这是一个例子：

def scrape_comments(reddit_api, csv_file, dest):
    df = pd.read_csv(csv_file)
    data = []
    for pid in df.id:
        try:
            # post_comment = []
            submission = reddit_api.submission(id=pid)
            submission.comments.replace_more(limit=None)
            for comment in submission.comments.list():
                # post_comment.append(comment.body)
                data.append((pid, comment.id, comment.parent_id, comment.body, comment.link_id,comment.author, comment.score, comment.created_utc, comment.subreddit))
            # data.append((pid, ";".join(post_comment)))
        except Exception:
            print ("Error! Skip the Current subreddit")
    df = pd.DataFrame(data, columns=["post_id", "comment_id", "comment_parent_id", "comment_body", "comment_link_id","comment_author", "comment_score","comment_created","comment_subreddit"]) # append tuple
    df.to_csv(dest, index=False, encoding='utf-8')

为什么此 try/except 循环因错误而退出？

Why is this try/except loop exiting on errors?

python

try-except