不，标准YAML不包括任何类型的“import”或“include”语句。

据我所知，YAML中不直接支持include，你必须自己提供一种机制，然而，这通常很容易做到。

我在我的python应用程序中使用YAML作为配置语言，在这种情况下经常定义这样的约定:

>>> main.yml <<<
includes: [ wibble.yml, wobble.yml]

然后在我的(python)代码中:

import yaml
cfg = yaml.load(open("main.yml"))
for inc in cfg.get("includes", []):
   cfg.update(yaml.load(open(inc)))

唯一的缺点是include中的变量将总是覆盖main中的变量，并且没有办法通过改变“includes:”语句在main中出现的位置来改变优先级。yml文件。

稍微不同的一点是，YAML不支持include，因为它并不是像基于文件的标记那样专门设计的。如果你在AJAX请求的响应中得到一个包含，它意味着什么?

结合其他答案，这里是一个简短的解决方案，没有重载Loader类，它可以与任何加载器操作文件:

import json
from pathlib import Path
from typing import Any

import yaml


def yaml_include_constructor(loader: yaml.BaseLoader, node: yaml.Node) -> Any:
    """Include file referenced with !include node"""

    # noinspection PyTypeChecker
    fp = Path(loader.name).parent.joinpath(loader.construct_scalar(node)).resolve()
    fe = fp.suffix.lstrip(".")

    with open(fp, 'r') as f:
        if fe in ("yaml", "yml"):
            return yaml.load(f, type(loader))
        elif fe in ("json", "jsn"):
            return json.load(f)
        else:
            return f.read()


def main():
    loader = yaml.SafeLoader  # Works with any loader
    loader.add_constructor("!include", yaml_include_constructor)

    with open(...) as f:
        yml = yaml.load(f, loader)

PyTypeChecker的存在是为了防止pep检查警告预期类型'ScalarNode'，得到'节点'而不是通过节点:yaml。节点到loader.construct_scalar()。

如果yaml。加载输入流不是文件流，因为loader.name在这种情况下不包含路径:

class Reader(object):
    ...
    def __init__(self, stream):
        ...
        if isinstance(stream, str):
            self.name = "<unicode string>"
            ...
        elif isinstance(stream, bytes):
            self.name = "<byte string>"
            ...
        else:
            self.name = getattr(stream, 'name', "<file>")
            ...

在我的用例中，我知道只包含YAML文件，所以解决方案可以进一步简化:

def yaml_include_constructor(loader: yaml.Loader, node: yaml.Node) -> Any:
    """Include YAML file referenced with !include node"""
    with open(Path(loader.name).parent.joinpath(loader.construct_yaml_str(node)).resolve(), 'r') as f:
        return yaml.load(f, type(loader))


Loader = yaml.SafeLoader  # Works with any loader
Loader.add_constructor("!include", yaml_include_constructor)


def main():
    with open(...) as f:
        yml = yaml.load(f, Loader=Loader)

甚至是使用lambda的一行代码:

Loader = yaml.SafeLoader  # Works with any loader
Loader.add_constructor("!include",
                       lambda l, n: yaml.load(Path(l.name).parent.joinpath(l.construct_scalar(n)).read_text(), type(l)))

使用Symfony，它对yaml的处理将间接地允许您嵌套yaml文件。诀窍在于使用参数选项。例如:

common.yml

parameters:
    yaml_to_repeat:
        option: "value"
        foo:
            - "bar"
            - "baz"

config.yml

imports:
    - { resource: common.yml }
whatever:
    thing: "%yaml_to_repeat%"
    other_thing: "%yaml_to_repeat%"

其结果将与:

whatever:
    thing:
        option: "value"
        foo:
            - "bar"
            - "baz"
    other_thing:
        option: "value"
        foo:
            - "bar"
            - "baz"

您的问题没有要求使用Python解决方案，但这里有一个使用PyYAML的解决方案。

PyYAML允许您将自定义构造函数(例如!include)附加到YAML加载器。我已经包含了一个可以设置的根目录，以便这个解决方案支持相对和绝对文件引用。

基于类的解决方案

这是一个基于类的解决方案，避免了我原始响应的全局根变量。

请参阅以下要点，了解一个类似的、更健壮的Python 3解决方案，该解决方案使用元类注册自定义构造函数。

import yaml
import os

class Loader(yaml.SafeLoader):

    def __init__(self, stream):

        self._root = os.path.split(stream.name)[0]

        super(Loader, self).__init__(stream)

    def include(self, node):

        filename = os.path.join(self._root, self.construct_scalar(node))

        with open(filename, 'r') as f:
            return yaml.load(f, Loader)

Loader.add_constructor('!include', Loader.include)

一个例子:

foo.yaml

a: 1
b:
    - 1.43
    - 543.55
c: !include bar.yaml

bar.yaml

- 3.6
- [1, 2, 3]

现在可以使用以下方法加载文件:

>>> with open('foo.yaml', 'r') as f:
>>>    data = yaml.load(f, Loader)
>>> data
{'a': 1, 'b': [1.43, 543.55], 'c': [3.6, [1, 2, 3]]}

我举了一些例子供你参考。

import yaml

main_yaml = """
Package:
 - !include _shape_yaml    
 - !include _path_yaml
"""

_shape_yaml = """
# Define
Rectangle: &id_Rectangle
    name: Rectangle
    width: &Rectangle_width 20
    height: &Rectangle_height 10
    area: !product [*Rectangle_width, *Rectangle_height]

Circle: &id_Circle
    name: Circle
    radius: &Circle_radius 5
    area: !product [*Circle_radius, *Circle_radius, pi]

# Setting
Shape:
    property: *id_Rectangle
    color: red
"""

_path_yaml = """
# Define
Root: &BASE /path/src/

Paths: 
    a: &id_path_a !join [*BASE, a]
    b: &id_path_b !join [*BASE, b]

# Setting
Path:
    input_file: *id_path_a
"""


# define custom tag handler
def yaml_import(loader, node):
    other_yaml_file = loader.construct_scalar(node)
    return yaml.load(eval(other_yaml_file), Loader=yaml.SafeLoader)


def yaml_product(loader, node):
    import math
    list_data = loader.construct_sequence(node)
    result = 1
    pi = math.pi
    for val in list_data:
        result *= eval(val) if isinstance(val, str) else val
    return result


def yaml_join(loader, node):
    seq = loader.construct_sequence(node)
    return ''.join([str(i) for i in seq])


def yaml_ref(loader, node):
    ref = loader.construct_sequence(node)
    return ref[0]


def yaml_dict_ref(loader: yaml.loader.SafeLoader, node):
    dict_data, key, const_value = loader.construct_sequence(node)
    return dict_data[key] + str(const_value)


def main():
    # register the tag handler
    yaml.SafeLoader.add_constructor(tag='!include', constructor=yaml_import)
    yaml.SafeLoader.add_constructor(tag='!product', constructor=yaml_product)
    yaml.SafeLoader.add_constructor(tag='!join', constructor=yaml_join)
    yaml.SafeLoader.add_constructor(tag='!ref', constructor=yaml_ref)
    yaml.SafeLoader.add_constructor(tag='!dict_ref', constructor=yaml_dict_ref)

    config = yaml.load(main_yaml, Loader=yaml.SafeLoader)

    pk_shape, pk_path = config['Package']
    pk_shape, pk_path = pk_shape['Shape'], pk_path['Path']
    print(f"shape name: {pk_shape['property']['name']}")
    print(f"shape area: {pk_shape['property']['area']}")
    print(f"shape color: {pk_shape['color']}")

    print(f"input file: {pk_path['input_file']}")


if __name__ == '__main__':
    main()

输出

shape name: Rectangle
shape area: 200
shape color: red
input file: /path/src/a

更新2

你可以把它们结合起来，像这样

# xxx.yaml
CREATE_FONT_PICTURE:
  PROJECTS:
    SUNG: &id_SUNG
      name: SUNG
      work_dir: SUNG
      output_dir: temp
      font_pixel: 24


  DEFINE: &id_define !ref [*id_SUNG]  # you can use config['CREATE_FONT_PICTURE']['DEFINE'][name, work_dir, ... font_pixel]
  AUTO_INIT:
    basename_suffix: !dict_ref [*id_define, name, !product [5, 3, 2]]  # SUNG30

# ↓ This is not correct.
# basename_suffix: !dict_ref [*id_define, name, !product [5, 3, 2]]  # It will build by Deep-level. id_define is Deep-level: 2. So you must put it after 2. otherwise, it can't refer to the correct value.