PostKit Validation Library

Validate post data before saving or publishing.

Installation

npm i postkit-validation-library

API

validateTitle

Validate a post title.

Takes in a title string and returns a validation result indicating whether the title is acceptable.

validateTitle(title: string, options?: ValidationOptions): ValidationResult

validateBody

Validate post body text.

Takes in a body string and returns a validation result indicating whether the content body is acceptable.

validateBody(body: string, options?: ValidationOptions): ValidationResult

validateStatus

Validate post status.

Takes in a status string and returns a validation result indicating whether the status is one of the allowed values.

validateStatus(status: string): ValidationResult

validatePost

Validate a full post object.

Takes in a Post object and returns a validation result indicating whether the post is valid as a whole.

validatePost(post: Post, options?: ValidationOptions): ValidationResult

isPostValid

Quick check for full-post validity.

Takes in a Post object and returns a boolean.

isPostValid(post: Post, options?: ValidationOptions): boolean

getPostValidationErrors

Return only validation issues for display.

Takes in a Post object and returns a list of validation issues.

getPostValidationErrors(post: Post, options?: ValidationOptions): ValidationIssue[]

Types

interface Post {
  id: string
  title: string
  body: string
  author: string
  tags: string[]
  category: string
  status: string
  createdAt: string
  updatedAt: string
}

interface ValidationIssue {
  field: 'title' | 'body' | 'status' | 'post'
  code: 'REQUIRED' | 'TOO_SHORT' | 'TOO_LONG' | 'INVALID_STATUS' | 'INVALID_TYPE'
  message: string
}

interface ValidationResult {
  valid: boolean
  issues: ValidationIssue[]
}

type PostStatus = 'draft' | 'review' | 'published'

Example Usage

import {
  validateTitle,
  validateBody,
  validateStatus,
  validatePost,
} from 'postkit-validation-library'

const post = {
  id: 'p1',
  title: 'Hello World',
  body: 'Some content for the post body with enough length.',
  author: 'Author',
  tags: ['writing'],
  category: 'General',
  status: 'published',
  createdAt: new Date().toISOString(),
  updatedAt: new Date().toISOString(),
}

validateTitle('My First Post')
// -> { valid: true, issues: [] }

validateTitle('')
// -> { valid: false, issues: [{ field: 'title', code: 'REQUIRED', message: 'title is required' }] }

validateBody('Some content for the post body.')
// -> { valid: true, issues: [] }

validateStatus('draft')
// -> { valid: true, issues: [] }

validateStatus('pending')
// -> { valid: false, issues: [{ field: 'status', code: 'INVALID_STATUS', message: 'status must be one of: draft, review, published' }] }

validatePost(post)
// -> { valid: true, issues: [] }

validatePost({ ...post, title: '', body: '', status: 'bad' as any })
// -> { valid: false, issues: [{...}, {...}, {...}] }

Edge Cases

• Empty or whitespace-only title should fail.
• Body text that is empty or too short should fail.
• Invalid status values (including wrong casing like "Draft") should fail.
• Missing fields in partially filled form data should return issues, not crash.
• Leading/trailing whitespace should be handled consistently by validation rules.
• Non-object inputs to validatePost (for example null or []) return INVALID_TYPE.
• Type mismatches (non-string title/body/status) return INVALID_TYPE.

Design Notes

• Main validators return a consistent ValidationResult shape for predictable app integration.
• Convenience helpers are included for common UI flows: boolean checks and field error rendering.
• validatePost aggregates title, body, and status checks so rules stay consistent in one place.
• Validators return structured issues instead of throwing on common invalid input.