CLI Usage

Use Property Validator from the command line to validate JSON files against schemas.

Installation

cd property-validator
npm link  # Enable 'propval' command globally

Basic Usage

Validate JSON File

propval --schema schema.json --data data.json

Example schema.json:

{
  "type": "object",
  "properties": {
    "name": { "type": "string" },
    "age": { "type": "number" }
  }
}

Example data.json:

{
  "name": "Alice",
  "age": 30
}

Output:

✓ Validation passed

Validation Failure

propval --schema schema.json --data invalid.json

Output:

✗ Validation failed at age: expected number, got string

CLI Options

• --schema <file> — Path to JSON schema file (required)
• --data <file> — Path to JSON data file to validate (required)
• --verbose — Show detailed error information
• --json — Output results as JSON
• --help — Show help message

Output Modes

Standard Output (Default)

propval --schema schema.json --data data.json

Output:

✓ Validation passed

JSON Output

propval --schema schema.json --data data.json --json

Output:

{
  "ok": true,
  "value": {
    "name": "Alice",
    "age": 30
  }
}

Verbose Mode

propval --schema schema.json --data invalid.json --verbose

Output:

✗ Validation failed

Error Details:
  Path: age
  Expected: number
  Actual: string
  Value: "thirty"

Full error: Validation failed at age: expected number, got string

Exit Codes

• 0 — Validation passed
• 1 — Validation failed
• 2 — Invalid arguments or file not found

Examples

Validate API Response

# Fetch API response
curl https://api.example.com/user/1 > response.json

# Validate against schema
propval --schema user-schema.json --data response.json

Validate Configuration File

propval --schema config-schema.json --data config.json

Batch Validation

# Validate multiple files
for file in data/*.json; do
  propval --schema schema.json --data "$file" || echo "Failed: $file"
done

Next Steps

• Library Usage - Use in your code
• Examples - Real-world scenarios
• API Reference - Complete API