基于布尔表达式查询含指定关键词的JSON文件名

Got it, let's tackle this problem step by step. The goal is to filter JSON files based on boolean queries against their keyword fields, right? Here's a practical, Python-based solution that handles all the cases you mentioned, including & (AND), ! (NOT), | (OR), and even nested combinations.

核心思路 #

We need to do two key things:

1. Extract the full set of keywords from each JSON file's keyword field.
2. Parse the user's boolean query into executable logic, then check which files match the query.

1. Extract Keywords from JSON Files #

First, let's write a helper function to read each JSON file and pull out its keywords. We'll handle both array-style keywords (like "keyword": ["Alabama", "Washington"]) and comma-separated string formats (in case your JSON has typos like the example you shared).

import json
from pathlib import Path

def extract_keywords(json_file):
    try:
        with open(json_file, 'r') as f:
            data = json.load(f)
            raw_keywords = data.get('keyword', [])
            
            # Handle comma-separated strings (if your JSON uses this format)
            if isinstance(raw_keywords, str):
                keywords = {kw.strip() for kw in raw_keywords.split(',')}
            else:
                # Assume it's an array/list of keywords
                keywords = set(raw_keywords)
            
            return keywords
    except Exception as e:
        print(f"⚠️  Error processing {json_file}: {str(e)}")
        return set()

2. Parse & Execute Boolean Queries #

Next, we need to convert the user's query string (like "Washington & !Alabama") into valid Python logic. We'll replace the query's syntax with Python's built-in logical operators and evaluate the condition against each file's keyword set.

import re

def matches_query(query, file_keywords):
    # Extract all quoted keywords from the query
    quoted_keywords = re.findall(r'"([^"]+)"', query)
    
    # Replace each quoted keyword with a check for membership in the file's keywords
    transformed_query = query
    for kw in quoted_keywords:
        transformed_query = transformed_query.replace(f'"{kw}"', f'"{kw}" in file_keywords')
    
    # Map custom boolean operators to Python's syntax
    transformed_query = (
        transformed_query
        .replace('&', 'and')
        .replace('|', 'or')
        .replace('!', 'not ')
    )
    
    # Safely evaluate the query (only safe if you control the input queries!)
    try:
        return eval(transformed_query)
    except SyntaxError:
        print(f"❌ Invalid query syntax: {query}")
        return False

3. Main Script: Tie It All Together #

Finally, a main function that handles command-line input, iterates over the specified files, and prints the ones that match the query.

def main():
    import sys
    if len(sys.argv) < 3:
        print("Usage: python query.py <boolean_query> <file1.json> <file2.json> ...")
        print("Example: python query.py \"\\\"Washington\\\" & !\\\"Alabama\\\"\" 02.json")
        sys.exit(1)
    
    query = sys.argv[1]
    file_paths = sys.argv[2:]
    
    for file_path in file_paths:
        path = Path(file_path)
        if not path.exists():
            print(f"⚠️  File {file_path} not found")
            continue
        if path.suffix != '.json':
            print(f"⚠️  {file_path} is not a JSON file")
            continue
        
        file_keywords = extract_keywords(path)
        if matches_query(query, file_keywords):
            print(path.name)

if __name__ == "__main__":
    main()

Usage Examples #

Let's test this with your sample cases:

1. Match files containing "Washington" #

python query.py "\"Washington\"" 01.json 02.json

Output:

01.json
02.json

2. Match files with "Washington" but NOT "Alabama" #

python query.py "\"Washington\" & !\"Alabama\"" 02.json

Output:

02.json

3. Match files with "Alabama" OR "Pennsylvania" #

python query.py "\"Alabama\" | \"Pennsylvania\"" 01.json 02.json

Output:

01.json
02.json

Important Notes #

• Command-line Quoting: In bash/zsh, you need to escape inner quotes (like \") or wrap the entire query in single quotes (e.g., ' "Washington" & !"Alabama" ').
• JSON Format: The code handles both array and comma-separated string keyword fields. If your JSON uses another format, adjust the extract_keywords function accordingly.
• Query Safety: Using eval() is safe here only if you trust the input queries. If this script will handle untrusted user input, you'll need a proper boolean expression parser instead (like using pyparsing to build an abstract syntax tree).

内容的提问来源于stack exchange，提问作者nightcod3r