desert_mirage_lib.py 文件源码

def json_config(jfile, jobj_hook=None, jwrite_obj=None, jappend=None):
    """
    Simple interface to json library functions. Reads JSON data into object
    dictionary or appends json data to existing file.
    See the json library documentation for  more info.
    `json <https://docs.python.org/3/library/json.html>`_

    Parameters
    ----------
    jfile : str
        json file path.
    jobj_hook : function (default: None)
        Decoder. If None, decodes to dict.
    jwrite_obj : obj (default: None)
        Obj to write to existing json file ``jfile``. 
        Evaluated before ``jappend``.
    jappend : obj (default: None)
        New data to append to existing json file ``jfile``.
    """
    # write if file does not exist.
    if jwrite_obj is not None:
        # Write `jwrite_obj` if file does not exist.
        if not any([os.path.isfile(jfile),
                    os.path.isfile(os.path.abspath(jfile)),
                    jwrite_obj]):
            print('writing `jwrite_obj` to new json `jfile`.')
            with open(jfile, 'w') as f:
                json.dump(jwrite_obj, f, sort_keys=True, ensure_ascii=False)
        else:
            print('No json in path provided.')
        return
    if jappend is not None:
        with open(jfile, 'r+') as f:
            json_dict = json.load(f, object_hook=None)
            json_dict.update(jappend)
            f.seek(0)
            f.truncate()  # todo: Improve to only truncate if needed.
            # print(len(f.readlines()))
            json.dump(json_dict, f, sort_keys=True, indent=4)
            f.close()
        return
    with open(jfile) as f:
        if jobj_hook is not None:
            return json.load(f, object_hook=jobj_hook)
        return json.load(f)