JSON Schema & Mock

JSON Schema & Mock

Generate JSON Schema and create mock data from schemas.

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Generate JSON Schema and create mock data from schemas.

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Highlights
  • JSON → JSON Schema
  • Infer required fields, strict objects and formats
  • Infer semantic hints and emit optional extensions
  • Schema → Mock Data
  • Choose between fixed and random sample strategies
JSON-to-Schema Controls
  • Required strategy
    • `all-observed`: mark every observed field as required
    • `none`: emit no `required`
    • `array-sample-based`: only keep fields present in every object inside array samples
  • Strict objects emit `additionalProperties: false` on object nodes when enabled, and allow extra fields by default when disabled
  • Format inference adds standard formats such as `email`, `uri`, `date`, `time`, `date-time`, `uuid`, `ipv4` and `ipv6`
  • Semantic inference uses field names and values to infer stronger meaning that can affect the generated schema
  • Numeric-string strategy
    • `preserve-string`: keep values like `"123"` as strings
    • `promote-primitive`: promote safe numeric-like strings toward `integer`, `number` or `boolean` semantics
  • Semantic extensions control whether fields such as `x-semantic-type` are emitted
Schema-to-Mock Controls
  • Regenerate rotates the internal seed so the same schema can produce another sample
  • Value strategy
    • `fixed`: return stable example values
    • `random`: return seed-driven pseudo-random output
  • Array length sets the target size before `minItems` / `maxItems` constraints clamp it
  • Property strategy
    • `all-properties`: emit all declared properties
    • `required-only`: emit only properties listed in `required`
  • Field-name fallback keeps inferring semantics such as `email`, `time`, `date-time`, `phone`, `price` and `age` when explicit schema hints are missing
  • Semantic string generation prefers `format`, `x-semantic-type` and field-name hints to produce more domain-shaped string values
Common uses
  • Generate JSON Schema from a sample JSON payload
  • Generate mock data quickly from an existing JSON Schema
  • Prepare structure rules and sample payloads for validation, docs or tests
  • Chain JSON samples, schema generation and mock data into one modeling flow
Notes
  • Schema-to-mock generation resolves local `$ref` entries in `definitions` and `$defs`; external references must be expanded first.