Simple Explanation On This Error In Understandable Form
1. Use Spaces Not Tabs
YAML relies on consistent spacing to denote structure. Do not use tab characters for indentation. Always use 2 or 4 spaces instead. Mixing tabs and spaces can cause problems.
2. Align All Keys In A Mapping
A mapping is like a dictionary in Python code. All of the keys within a single mapping must align vertically using the same number of spaces :
user:
name: John
age: 30
Having values indented unevenly will cause parsing issues :
user:
name: John
age: 30 #inconsistent indentation
3. Increase Indentation For Nested Mappings
When you nest a mapping inside another mapping, increase the number of spaces to indent it further :
profile:
name: John
contact:
email: john@test.com #nested mapping indented further
This helps YAML understand the levels of related data visibly through indentation. Aligning all keys and properly indenting nested mappings avoids confusing the parser.
How Do I Resolve A “Mapping Values Are Not Allowed Here” Error In YAML?
The “Mapping Values not allowed” YAML error typically occurs due to inconsistent indentation, improper nesting of mappings and sequences, or unquoted mapping keys that conflict with YAML syntax.
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