python - 如何将数据附加到 YAML 文件

Question

我有一个文件*.yaml，内容如下:

bugs_tree:
  bug_1:
    html_arch: filepath
    moved_by: user1
    moved_date: '2018-01-30'
    sfx_id: '1'

我想在节点 [bugs_tree] 下的这个文件中添加一个新的子元素我已尝试按以下方式执行此操作:

if __name__ == "__main__":
    new_yaml_data_dict = {
        'bug_2': {
            'sfx_id': '2', 
            'moved_by': 'user2', 
            'moved_date': '2018-01-30', 
            'html_arch': 'filepath'
        }
    }

    with open('bugs.yaml','r') as yamlfile:
        cur_yaml = yaml.load(yamlfile)
        cur_yaml.extend(new_yaml_data_dict)
        print(cur_yaml)

然后文件应该是这样的:

bugs_tree:
  bug_1:
    html_arch: filepath
    moved_by: username
    moved_date: '2018-01-30'
    sfx_id: '1234'
  bug_2:
    html_arch: filepath
    moved_by: user2
    moved_date: '2018-01-30'
    sfx_id: '2'

当我尝试执行 .append() 或 .extend() 或 .insert() 时出现错误

cur_yaml.extend(new_yaml_data_dict)
AttributeError: 'dict' object has no attribute 'extend'

Answer 1

如果你想更新文件，读取是不够的。您还需要针对该文件再次写入。这样的事情会起作用:

with open('bugs.yaml','r') as yamlfile:
    cur_yaml = yaml.safe_load(yamlfile) # Note the safe_load
    cur_yaml['bugs_tree'].update(new_yaml_data_dict)

if cur_yaml:
    with open('bugs.yaml','w') as yamlfile:
        yaml.safe_dump(cur_yaml, yamlfile) # Also note the safe_dump

我没有对此进行测试，但他的想法是您使用读取 来读取 文件并写入 到写入文件。使用 safe_load 和 safe_dump 像 Anthon说:

"There is absolutely no need to use load(), which is documented to be unsafe. Use safe_load() instead"