util.py 文件源码

def asjson(obj, seen=None):
    if isinstance(obj, collections.Mapping) or isiter(obj):
        # prevent traversal of recursive structures
        if seen is None:
            seen = set()
        elif id(obj) in seen:
            return '__RECURSIVE__'
        seen.add(id(obj))

    if hasattr(obj, '__json__') and type(obj) is not type:
        return obj.__json__()
    elif isinstance(obj, collections.Mapping):
        result = collections.OrderedDict()
        for k, v in obj.items():
            try:
                result[asjson(k, seen)] = asjson(v, seen)
            except TypeError:
                debug('Unhashable key?', type(k), str(k))
                raise
        return result
    elif isiter(obj):
        return [asjson(e, seen) for e in obj]
    else:
        return obj