About

UnzipKit is an Objective-C zlib wrapper for compressing and decompressing Zip files on OS X and iOS. It's based on the AgileBits fork of Objective-Zip, developed by Flying Dolphin Studio.

It provides the following over Objective-Zip:

• A simpler API, with only a handful of methods, and no incantations to remember
• The ability to delete files in an archive, including overwriting an existing file
• Pervasive use of blocks, making iteration and progress reporting simple to use
• Full documentation for all methods
• Pervasive use of NSError, instead of throwing exceptions

Installation

UnzipKit supports both CocoaPods and Carthage. CocoaPods does not support dynamic framework targets (as of v0.39.0), so in that case, please use Carthage.

Cartfile:

github "abbeycode/UnzipKit"

Podfile:

pod "UnzipKit"

Deleting files

Using the method -deleteFile:error: currently creates a new copy of the archive in a temporary location, without the deleted file, then replaces the original archive. By default, all methods to write data perform a delete on the file name they write before archiving the new data. You can turn this off by calling the overload with an overwrite argument, setting it to NO. This will not remove the original copy of that file, though, causing the archive to grow with each write of the same file name.

If that's not a concern, such as when creating a new archive from scratch, it would improve performance, particularly for archives with a large number of files.

NSError *archiveError = nil;
UZKArchive *archive = [UZKArchive zipArchiveAtPath:@"An Archive.zip" error:&archiveError];
BOOL deleteSuccessful = [archive deleteFile:@"dir/anotherFilename.jpg"
                                      error:&error];

Detecting Zip files

You can quickly and efficiently check whether a file at a given path or URL is a Zip archive:

BOOL fileAtPathIsArchive = [UZKArchive pathIsAZip:@"some/file.zip"];

NSURL *url = [NSURL fileURLWithPath:@"some/file.zip"];
BOOL fileAtURLIsArchive = [UZKArchive urlIsAZip:url];

Reading Zip contents

NSError *archiveError = nil;
UZKArchive *archive = [UZKArchive zipArchiveAtPath:@"An Archive.zip" error:&archiveError];
NSError *error = nil;

You can use UnzipKit to perform these read-only operations:

• List the contents of the archive

  NSArray<NSString*> *filesInArchive = [archive listFilenames:&error];

• Extract all files to disk

  BOOL extractFilesSuccessful = [archive extractFilesTo:@"some/directory"
                                              overWrite:NO
                                               progress:
  ^(UZKFileInfo *currentFile, CGFloat percentArchiveDecompressed) {
      NSLog(@"Extracting %@: %f%% complete", currentFile.filename, percentArchiveDecompressed);
  }
                                                  error:&error];

• Extract each archived file into memory

  NSData *extractedData = [archive extractDataFromFile:@"a file in the archive.jpg"
                                              progress:^(CGFloat percentDecompressed) {
                                                  NSLog(@"Extracting, %f%% complete", percentDecompressed);
                                              }
                                                 error:&error];

Modifying archives

NSError *archiveError = nil;
UZKArchive *archive = [UZKArchive zipArchiveAtPath:@"An Archive.zip" error:&archiveError];
NSError *error = nil;
NSData *someFile = // Some data to write

You can also modify Zip archives:

• Write an in-memory NSData into the archive

  BOOL success = [archive writeData:someFile
                           filePath:@"dir/filename.jpg"
                              error:&error];

• Write data as a stream to the archive (from disk or over the network), using a block:

  BOOL success = [archive writeIntoBuffer:@"dir/filename.png"
                                    error:&error
                                    block:
      ^BOOL(BOOL(^writeData)(const void *bytes, unsigned int length), NSError**(actionError)) {
          for (NSUInteger i = 0; i <= someFile.length; i += bufferSize) {
              const void *bytes = // some data
              unsigned int length = // length of data
  
              if (/* Some error occurred reading the data */) {
                  *actionError = // Any error that was produced, or make your own
                  return NO;
              }
  
              if (!writeData(&bytes, length)) {
                  return NO;
              }
          }
  
          return YES;
      }];

• Delete files from the archive

  BOOL success = [archive deleteFile:@"No-good-file.txt" error:&error];

Documentation

Full documentation for the project is available on CocoaDocs.

Pushing a new CocoaPods version

New tagged builds (in any branch) get pushed to CocoaPods automatically, provided they meet the following criteria:

1. All builds and tests succeed
2. The library builds successfully for CocoaPods and for Carthage
3. The build is tagged with something resembling a version number (#.#.#(-beta#), e.g. 2.9 or 2.9-beta5)
4. pod spec lint passes, making sure the CocoaPod is 100% valid

Before pushing a build, you must:

1. Add the release notes to the CHANGELOG.md, and commit

2. Run set-version, like so:

   ./Scripts/set-version.sh <version number>

   This does the following:

   1. Updates the various Info.plist files to indicate the new version number, and commits them
   2. Makes an annotated tag whose message contains the release notes entered in Step 1

Once that's done, you can call git push --follow-tags ¹, and let Travis CI take care of the rest.

License

• UnzipKit: See LICENSE (BSD)
• MiniZip: See MiniZip website

---

1: Or set followTags = true in your git config to always get this behavior:

git config --global push.followTags true

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