def remove_nulls(data):
"""Remove None-valued keys from a dictionary, recursively."""
if isinstance(data, dict):
for k, v in data.items():
if v is None:
data.pop(k)
data[k] = remove_nulls(v)
elif is_list(data):
data = [remove_nulls(d) for d in data if d is not None]
return data
def merge_docs(old, new):
"""Exend the values of the new doc with extra values from the old."""
old = remove_nulls(old)
new = dict(remove_nulls(new))
for k, v in old.items():
if k in new:
if is_list(v):
v = new[k] + v
new[k] = unique_list(v)
elif isinstance(v, dict):
new[k] = merge_docs(v, new[k])
else:
new[k] = v
return new