compare yaml files, report diff in tags, recursively

yamldiff.py

def rdiff(yamla, yamlb, path='', key=getkey):
  if isinstance(yamla, list) and isinstance(yamlb, list):
    for d in listdiff(yamla, yamlb, path=path, key=key):
      yield d
  elif isinstance(yamla, dict) and isinstance(yamlb, dict):
    for d in dictdiff(yamla, yamlb, path=path, key=key):
      yield d
  else:
    if yamla != yamlb:
      yield (path, 'value_difference', yamla, '-->', yamlb)
      

def listdiff(yamla, yamlb, path, key):
  """ compute the differences between two lists, as a generator
  
  :param list yamla: list of python objects
  :param list yamlb: list of python objects
  :param str path: path of current node (same idea as XPath)
  :param callable key: key lambda used for sorting
  
  """
  
  yamla = {key(v, i): v for i, v in enumerate(yamla)}
  yamlb = {key(v, i): v for i, v in enumerate(yamlb)}
  keysa = set(yamla.keys())
  keysb = set(yamlb.keys())
  
    for a in [k for k in keysb.difference(keysa)]:
        yield (path + '/' + a, 'added')
    for m in [k for k in keysa.difference(keysb)]:
        yield (path + '/' + m, 'missing')

    common = [k for k in keysa.intersection(keysb) if k]
    for k in common:
        if (isinstance(yamla[k], list) and isinstance(yamlb, list)) \
           or (isinstance(yamla[k], dict) and isinstance(yamlb, dict)):
            for d in rdiff(yamla[k], yamlb[k], path + '/' + k):
                yield d
        else:
            for d in rdiff(yamla[k], yamlb[k], path + '/' + k, key):
                yield d


def dictdiff(yamla, yamlb, path, key):
    """compute the difference between two dictionaries, as a generator

    :param dict yamla: first dictionary
    :param dict yamlb: second dictionary to compare with first one
    :param str path: path of current node (same idea as XPath)
    :param callable key: key lambda used for sorting

    """
    keysa = set(yamla.keys())
    keysb = set(yamlb.keys())

    for a in [k for k in keysb.difference(keysa)]:
        yield (path + '/' + a, 'added')
    for m in [k for k in keysa.difference(keysb)]:
        yield (path + '/' + m, 'missing')

    common = [k for k in keysa.intersection(keysb) if k]
    for k in common:
        if (isinstance(yamla[k], list) and isinstance(yamlb[k], list)) \
           or (isinstance(yamla[k], dict) and isinstance(yamlb[k], dict)):
            for d in rdiff(yamla[k], yamlb[k], path + '/' + k, key):
                yield d
        else:
            for d in rdiff(yamla[k], yamlb[k], path + '/' + k, key):
                yield d
    

i am using your code to help learn python. Can you let me know what the getkey function looks like. This way i can run it to see how it works and what it does