Question

I am attempting to search a directory for a given string pattern in Python. I then want to assemble the matches into an array.

At first, I was trying to use grep:

regex = " dojo.require(..*) "
bashCommand = "grep"+" --only-matching -r -h"+regex+baseDir
process = subprocess.Popen(bashCommand.split(), stdout=subprocess.PIPE)
dirStr = process.communicate()[0]

But I realized I needed to support strings on multiple lines, such as

dojo.require(
"abc"(;

so grep is not an option.

What other ways can I accomplish this? Thanks in advance.

Answer 1

Rather than calling grep, you could implement this functionality in pure Python using a combination of os and re. Use the re.DOTALL flag to allow multi-line matches. For example:

import re, os

def grep(regex, base_dir):
    compiled_regex = re.compile(regex, re.DOTALL)
    matches = list()
    for filename in os.listdir(base_dir):
        full_filename = os.path.join(base_dir, filename)
        if not os.path.isfile(full_filename):
            continue
        with open(os.path.join(base_dir, filename)) as fh:
            content = fh.read()
            if compiled_regex.search(content):
                matches.append(full_filename)
    return matches

print grep(" dojo.require(..*) ", ".")