In-Memory Zip in Python
Below is a post of mine from May of 2008 on zipping in memory with Python, re-posted since Posterous is shutting down.
I recently noticed that there is a for-pay component available to zip files in-memory with Python. Considering this is something that should be free, I threw together the following code. It has only gone through very basic testing, so if anyone finds any errors, let me know and I’ll update this.
import zipfile import StringIO class InMemoryZip(object): def __init__(self): # Create the in-memory file-like object self.in_memory_zip = StringIO.StringIO() def append(self, filename_in_zip, file_contents): '''Appends a file with name filename_in_zip and contents of file_contents to the in-memory zip.''' # Get a handle to the in-memory zip in append mode zf = zipfile.ZipFile(self.in_memory_zip, "a", zipfile.ZIP_DEFLATED, False) # Write the file to the in-memory zip zf.writestr(filename_in_zip, file_contents) # Mark the files as having been created on Windows so that # Unix permissions are not inferred as 0000 for zfile in zf.filelist: zfile.create_system = 0 return self def read(self): '''Returns a string with the contents of the in-memory zip.''' self.in_memory_zip.seek(0) return self.in_memory_zip.read() def writetofile(self, filename): '''Writes the in-memory zip to a file.''' f = file(filename, "w") f.write(self.read()) f.close() if __name__ == "__main__": # Run a test imz = InMemoryZip() imz.append("test.txt", "Another test").append("test2.txt", "Still another") imz.writetofile("test.zip")