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This rule belongs to the openapi-v3-syntax-linting ruleset and states that:

The unique key of each entry in the Schema Object patternProperties property must be a valid regular expression, according to the ECMA-262 regular expression dialect. It is recommended to restrict yourself to following regular expression tokens: individual Unicode characters, as defined by the JSON specification [RFC8259], simple character classes ([abc]), range character classes ([a-z]), complemented character classes ([^abc], [^a-z]), simple quantifiers: + (one or more), * (zero or more), ? (zero or one), and their lazy versions (+?, *?, ??), range quantifiers: {x} (exactly x occurrences), {x,y} (at least x, at most y, occurrences), {x,} (x occurrences or more), and their lazy versions, the beginning-of-input (^) and end-of-input ($) anchors.

Maximum SeverityWarning
MessageKey provided for the Schema Object patternProperties entry is invalid.
Rule SystemSyntax
Broad CategorySchemas
Products ImpactedAPI Transformer, Code Generation, Developer Experience Portal
Tagsopenapi3 openapi syntax linting regex pattern pattern properties json schema schema

Suggested Fixes

  • Ensure that the key value is a valid regex expression.
  • Ensure that the key value is properly escaped i.e. any reserved characters are appropriately handled.
  • Ensure that the regex expression is valid according to the ECMA 262 dialect of regular expressions.
  • Ensure that the regex pattern uses allowed tokens only.

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