Question

我使用的是python 2.7并使用PyYAML-3.10

以下是我的yaml文件：

host:localhost
username:root
password:test
database:test
operations_database:operations
treeroot:
    branch1:
        name: Node 1
        branch1-1:
            name: Node 1-1
    branch2:
        name: Node 2
        branch2-1:
            name: Node 2-1

当我运行以下代码时，我得到以下错误。但是，如果删除treeroot上方的行，则代码可以正常工作：

from yaml import load, dump
try:
    from yaml import CLoader as Loader, CDumper as Dumper
except ImportError:
    from yaml import Loader, Dumper
f=open('amazon.yaml')  
data = load(f, Loader=Loader) 

Traceback (most recent call last):
  File "/home/ubuntu/workspace/Amazon-Products-Crawler-1/config_files/test_yaml.py", line 10, in <module>
    data = load(f, Loader=Loader) 
  File "/usr/local/lib/python2.7/dist-packages/yaml/__init__.py", line 71, in load
    return loader.get_single_data()
  File "/usr/local/lib/python2.7/dist-packages/yaml/constructor.py", line 37, in get_single_data
    node = self.get_single_node()
  File "/usr/local/lib/python2.7/dist-packages/yaml/composer.py", line 36, in get_single_node
    document = self.compose_document()
  File "/usr/local/lib/python2.7/dist-packages/yaml/composer.py", line 58, in compose_document
    self.get_event()
  File "/usr/local/lib/python2.7/dist-packages/yaml/parser.py", line 118, in get_event
    self.current_event = self.state()
  File "/usr/local/lib/python2.7/dist-packages/yaml/parser.py", line 193, in parse_document_end
    token = self.peek_token()
  File "/usr/local/lib/python2.7/dist-packages/yaml/scanner.py", line 128, in peek_token
    self.fetch_more_tokens()
  File "/usr/local/lib/python2.7/dist-packages/yaml/scanner.py", line 220, in fetch_more_tokens
    return self.fetch_value()
  File "/usr/local/lib/python2.7/dist-packages/yaml/scanner.py", line 580, in fetch_value
    self.get_mark())
yaml.scanner.ScannerError: mapping values are not allowed here
  in "amazon.yaml", line 6, column 9

Answer 1

尝试在冒号后放置空格。

Answer 2

yaml文件不接受文件内容中冒号后面的值。在空格后输入值，保存文件并再次运行，错误将消失。我在使用BDD进行自动化时遇到了类似的错误，经过大量调试后得到了修复。

Answer 3

对于任何来这里并发现即使冒号后面有空格的人，他们仍然会收到此错误

如果您从某种格式的源复制yaml文本（对我来说这是一条Slack消息），您也会收到此错误。这将以无形的方式交换标准YAML读取器无法读取但看起来相同的非ASCII字符。

解决方案是仅从原始非ASCII源进行复制。

Answer 4

如果有人来到这里并正确设置了格式和空格，但错误仍然存在。

检查版本后是否有冒号！（我面无表情的人）

错误：

version '3.7'

services:
  rabbitmq3:
    image: rabbitmq:3-management

已修复：

version: '3.7'

services:
  rabbitmq3:
    image: rabbitmq:3-management

Python和PYAML - yaml.scanner.ScannerError：此处不允许使用映射值

4 个答案: