JSON Key Extractor Component

The JSON Key Extractor component provides precise value extraction from JSON structures using key paths. It supports nested object traversal, array access, and strict validation while maintaining type safety and error handling.

JSON Key Extractor workflow and architecture

Configuration Parameters

Required Parameters

jsonString: Input JSON string to parse
keyPath: Path to desired value
- Dot notation: "user.address.city"
- Array access: "users[0].name"
- Mixed path: "data.items[2].details.id"

Optional Parameters

strictMode: Enable strict validation (default: false)
- Type checking
- Path validation
- Null checking

Output Format

{
  "extracted_value": any, // The extracted value of any valid JSON type
  "metadata": {
    "path": string,
    "value_type": string,
    "depth": number,
    "extraction_time": number
  },
  "validation": {
    "strict_mode": boolean,
    "type_check_passed": boolean,
    "path_valid": boolean,
    "value_present": boolean
  },
  "error": {
    "code": string,
    "message": string,
    "details": {
      "path_segment": string,
      "expected_type": string,
      "actual_type": string
    }
  } | null
}

Features

Nested object traversal
Array access support
Type validation
Strict mode validation
Error handling
Performance metrics
Path validation
Null safety

Note: Enable strict mode for sensitive data extraction. Handle potential null values appropriately.

Tip: Use dot notation for better readability. Implement error handling for missing paths.

Example Usage

const extractor = new JsonKeyExtractor();

// Simple key extraction
const result1 = await extractor.extract({
  jsonString: '{"user": {"name": "John", "age": 30}}',
  keyPath: "user.name",
  strictMode: false
});

// Array access with strict mode
const result2 = await extractor.extract({
  jsonString: `{
    "products": [
      {"id": 1, "details": {"price": 29.99}},
      {"id": 2, "details": {"price": 39.99}}
    ]
  }`,
  keyPath: "products[1].details.price",
  strictMode: true
});

// Complex nested path
const result3 = await extractor.extract({
  jsonString: `{
    "data": {
      "items": [
        {
          "category": {
            "subcategories": [
              {"name": "Electronics", "id": "e001"}
            ]
          }
        }
      ]
    }
  }`,
  keyPath: "data.items[0].category.subcategories[0].id",
  strictMode: true
});

Key Path Patterns:

// Simple path
"user.name"

// Array access
"users[0].address"

// Multiple array access
"data.items[0].subitems[2].id"

// Mixed notation
"organization.departments[0].employees[1].contact.phone"