aid: schema-validation
name: Schema Validation
description: >-
  Vocabulary and taxonomy for schema validation concepts, tools, patterns,
  and best practices in API development and governance.
version: '1.0'
created: '2026-05-02'
modified: '2026-05-02'
tags:
  - API Governance
  - JSON Schema
  - Schema Validation

terms:
  - term: Schema Validation
    definition: >-
      The process of verifying that a data structure (object, document, or API
      payload) conforms to a defined schema or specification. Schema validation
      enforces type constraints, required fields, format patterns, and value
      ranges.
    category: Core Concept
    aliases:
      - Schema Compliance
      - Data Validation

  - term: JSON Schema
    definition: >-
      A vocabulary for describing and validating JSON data structures. The IETF
      standard defines keywords like type, properties, required, format, minimum,
      maximum, enum, and pattern used to declare constraints on JSON data.
    category: Specification
    versions:
      - Draft 4
      - Draft 6
      - Draft 7
      - "2019-09"
      - "2020-12"

  - term: OpenAPI Validation
    definition: >-
      Validation of API request and response payloads against an OpenAPI
      specification's schema definitions. Includes validating path parameters,
      query parameters, request bodies, and response bodies.
    category: Use Case

  - term: Contract Testing
    definition: >-
      Testing that verifies an API implementation matches its declared contract
      (OpenAPI or JSON Schema spec). Tools like Schemathesis perform automated
      contract testing using property-based test generation.
    category: Use Case

  - term: JSON Schema Draft
    definition: >-
      A specific version of the JSON Schema specification. Each draft introduces
      new keywords and refines existing behavior. Draft 2020-12 is the current
      latest stable draft.
    category: Specification
    current_stable: "2020-12"

  - term: AJV
    definition: >-
      Another JSON Validator. The fastest JSON Schema validator for JavaScript,
      which compiles schemas to highly optimized JavaScript validation functions.
    category: Tool
    language: JavaScript
    url: https://ajv.js.org/

  - term: Hyperjump
    definition: >-
      A standards-compliant JSON Schema validation, annotation, and bundling
      library for JavaScript supporting all drafts and OpenAPI vocabularies.
    category: Tool
    language: JavaScript
    url: https://json-schema.hyperjump.io/

  - term: Spectral
    definition: >-
      An open-source JSON/YAML linter from Stoplight providing customizable
      rulesets for OpenAPI, AsyncAPI, and JSON Schema governance.
    category: Tool
    language: JavaScript
    url: https://stoplight.io/open-source/spectral

  - term: Validation Keyword
    definition: >-
      A JSON Schema keyword that defines a constraint on instance data.
      Examples include type, required, properties, minLength, maxLength,
      minimum, maximum, enum, pattern, and format.
    category: JSON Schema Concept

  - term: Validation Error
    definition: >-
      A structured report from a schema validator identifying the instance
      path, schema path, keyword, and message of a constraint violation.
    category: Output Format

  - term: Format Validation
    definition: >-
      Validation of string values against named formats like email, uri,
      date-time, ipv4, and uuid. Format validation may be assertion-based
      (strict) or annotation-based (informational).
    category: JSON Schema Concept

  - term: Schema Linting
    definition: >-
      Static analysis of schemas and API specifications for style, consistency,
      naming conventions, and governance policy compliance. Distinct from
      data validation (checking values against schemas).
    category: Use Case

  - term: JSON Path
    definition: >-
      A query language for selecting nodes within a JSON document, used in
      Spectral rules to target specific schema elements for validation.
    category: Tool Concept

  - term: Strict Mode
    definition: >-
      A validator configuration that causes additional or unknown schema
      keywords to be treated as errors rather than being silently ignored.
    category: Configuration

  - term: Schema Bundle
    definition: >-
      A JSON Schema document that combines multiple schemas (resolving $ref
      references) into a single self-contained file for portability and
      tooling compatibility.
    category: JSON Schema Concept

  - term: Ruleset
    definition: >-
      A configuration file (YAML or JSON) defining a collection of
      Spectral validation rules, each with a severity, target path,
      and validation function.
    category: Tool Concept

categories:
  - Core Concept
  - Specification
  - Use Case
  - Tool
  - JSON Schema Concept
  - Output Format
  - Configuration
  - Tool Concept