HOWTO: Git generate and read revision for XCode/ObjC

Git-Revision.md

git revision for Xcode

1. Install custom build phase In Xcode go to the project settings: Add build phase => Add run script and paste

    `which git` show  --abbrev-commit --pretty=oneline | head -1 | cut -d " " -f1 > revision
   

   This should go before Copy resource bundle

2. Add revision to Copy resource bundles

3. Load revision in Application by adding a Category on Application

    - (NSString*)revision {
      static NSString* revisionNumber = nil; 
      if (revisionNumber == nil) {
        NSString* revisionFile = [[NSBundle mainBundle] pathForResource:@"revision" ofType:nil];
        if (revisionFile) {
          NSData* data = [NSData dataWithContentsOfFile:revisionFile];
          NSString* fileContent = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
          revisionNumber = [fileContent stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
        }
        if (revisionNumber == nil) {
          revisionNumber = @"0000000";
        }
      }
      return revisionNumber; 
    }
   

   Can be added as a property as well.

4. Load the revision from your code

    [[UIApplication sharedApplication] revision]