如何编写Acestream正则表达式？从文本提取Acestream URL技术问询

Great question! Acestream URLs follow a consistent structure centered around a 40-character hexadecimal SHA-1 ID, so crafting a regex to pull them out of text is straightforward once you know the pattern.

Key Background #

A standard Acestream URL looks like this:
acestream://a1b2c3d4e5f6a7b8c9d0e1f2a3b4c5d6e7f8a9b0
Occasionally, you might see a suffix like /playlist.m3u8 added for direct playlist access.

Regex Patterns for Different Use Cases #

1. Match Full Standard Acestream URLs (Protocol + 40-char ID) #

Use this to capture the complete, basic URL:

acestream://[0-9a-fA-F]{40}

• Breakdown:
  • acestream://: Exact match for the Acestream protocol prefix
  • [0-9a-fA-F]{40}: Matches exactly 40 hexadecimal characters (0-9, A-F, a-f) — this is the unique stream ID

2. Match URLs with Optional Playlist Suffix #

If you need to account for URLs ending in /playlist.m3u8:

acestream://[0-9a-fA-F]{40}(/playlist\.m3u8)?

• The (/playlist\.m3u8)? part makes the playlist suffix optional (the ? means "zero or one occurrence")

3. Extract Only the Stream ID (Skip the Protocol Prefix) #

If you just want the 40-character ID without acestream://, use a positive lookbehind:

(?<=acestream://)[0-9a-fA-F]{40}

• (?<=acestream://): Ensures the ID is preceded by the protocol prefix, but doesn't include the prefix in the match result

Example Implementation (Python) #

Here's how you'd use these regexes in practice to extract URLs/IDs from a sample text:

import re

sample_text = """
Check out this sports stream: acestream://a1b2c3d4e5f6a7b8c9d0e1f2a3b4c5d6e7f8a9b0
Another one with playlist: acestream://f0e1d2c3b4a5f6e7d8c9b0a1f2e3d4c5b6a7f8e9/playlist.m3u8
"""

# Capture all full URLs (including optional playlist suffix)
full_urls = re.findall(r'acestream://[0-9a-fA-F]{40}(/playlist\.m3u8)?', sample_text, re.IGNORECASE)
# Extract only the stream IDs
stream_ids = re.findall(r'(?<=acestream://)[0-9a-fA-F]{40}', sample_text, re.IGNORECASE)

print("Full Acestream URLs:", full_urls)
print("Extracted Stream IDs:", stream_ids)

Pro Tips #

• Add re.IGNORECASE (or the equivalent flag in your regex engine) to handle both uppercase and lowercase hex characters
• If your text has URLs followed by punctuation (like commas or periods), add a word boundary \b or a lookahead (?=\s|$|,|\.) to avoid capturing extra characters:

  acestream://[0-9a-fA-F]{40}(/playlist\.m3u8)?(?=\s|$|,|\.)
  

内容的提问来源于stack exchange，提问作者BrunoRamalho