Docs Faker Functions Reference

Faker Reference for Mockarty

Table of Contents

  1. Faker Overview
  2. Basic Data Types
  3. Identifiers
  4. Personal Data
  5. Dates and Time
  6. Numeric Data
  7. Addresses and Locations
  8. Internet and Communication
  9. Business Data
  10. Localized Data
  11. Special Functions

Faker Overview

What is Faker?

Faker in Mockarty is a random test data generation system integrated with JsonPath for creating dynamic responses.

Key features:

  • Random data - generation of realistic test data
  • Localization - support for various languages and regions
  • Typing - specialized generators for different data types
  • Reproducibility - ability to control randomness

Usage Syntax

{
  "response": {
    "payload": {
      "id": "$.fake.UUID",
      "name": "$.fake.FirstName",
      "email": "$.fake.Email",
      "createdAt": "$.fake.RFC3339"
    }
  }
}

In Go Template syntax:

{
  "id": "{{.fake.UUID}}",
  "name": "{{.fake.FirstName}}",
  "email": "{{.fake.Email}}"
}

Basic Data Types

Strings and Text

Function Description Example
$.fake.Word Random word "lorem"
$.fake.Sentence Sentence "Lorem ipsum dolor sit amet."
$.fake.Paragraph Text paragraph "Lorem ipsum dolor sit amet..."
$.fake.Letter Random letter "A"
$.fake.Character Random character "x"

Usage examples:

{
  "response": {
    "payload": {
      "title": "$.fake.Sentence",
      "description": "$.fake.Paragraph",
      "keyword": "$.fake.Word",
      "code": "$.fake.Character"
    }
  }
}

Boolean Values

Function Description Example
$.fake.Bool Random boolean value true / false 
{
  "response": {
    "payload": {
      "isActive": "$.fake.Bool",
      "hasPermissions": "$.fake.Bool",
      "emailVerified": "$.fake.Bool"
    }
  }
}

Identifiers

UUID and Unique IDs

Function Description Example
$.fake.UUID UUID v4 "a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a11"
$.fake.UUIDDigit UUID digits only "123456789012345678901234567890123456"
$.fake.UUIDHyphenated UUID with hyphens "550e8400-e29b-41d4-a716-446655440000" 
{
  "response": {
    "payload": {
      "id": "$.fake.UUID",
      "userId": "$.fake.UUIDDigit",
      "sessionId": "$.fake.UUIDHyphenated",
      "trackingId": "TRK-$.fake.UUIDDigit"
    }
  }
}

Numeric Identifiers

Function Description Example
$.fake.Int Random integer 42
$.fake.PositiveInt Positive number 123
$.fake.NegativeInt Negative number -456
$.fake.IntBetween(min, max) Number in range $.fake.IntBetween(1, 100) -> 75 
{
  "response": {
    "payload": {
      "id": "$.fake.PositiveInt",
      "priority": "$.fake.IntBetween(1, 10)",
      "score": "$.fake.IntBetween(-100, 100)",
      "count": "$.fake.Int"
    }
  }
}

Personal Data

Names and Personal Information

Function Description Example
$.fake.FirstName First name "John"
$.fake.LastName Last name "Doe"
$.fake.Name Full name "John Doe"
$.fake.Username Username "johnDoe123"
$.fake.Gender Gender "male" / "female"

Localized names:

Function Description Example
$.fake.RussianFirstNameMale Russian male first name "Aleksandr"
$.fake.RussianFirstNameFemale Russian female first name "Anna"
$.fake.RussianLastNameMale Russian male last name "Ivanov"
$.fake.RussianLastNameFemale Russian female last name "Ivanova"
$.fake.ChineseFirstName Chinese first name "Wei"
$.fake.ChineseName Chinese full name "Li Wei"
$.fake.GermanFirstName German first name "Hans"

Examples:

{
  "response": {
    "payload": {
      "user": {
        "firstName": "$.fake.FirstName",
        "lastName": "$.fake.LastName",
        "fullName": "$.fake.Name",
        "username": "$.fake.Username",
        "gender": "$.fake.Gender"
      },
      "russianUser": {
        "name": "$.fake.RussianFirstNameMale",
        "surname": "$.fake.RussianLastNameMale"
      }
    }
  }
}

Dates and Time

Date Generators

Function Description Example
$.fake.Date Random date "1985-12-25"
$.fake.RFC3339 RFC3339 timestamp "2024-01-15T14:30:45Z"
$.fake.UnixTime Unix timestamp 1705315845
$.fake.FutureDate Future date "2025-06-15"
$.fake.PastDate Past date "2023-03-10"
$.fake.DateRange(start, end) Date in range Custom range

Time components:

Function Description Example
$.fake.Year Year 2024
$.fake.Month Month "March"
$.fake.MonthShort Month abbreviated "Mar"
$.fake.Day Day 15
$.fake.WeekDay Day of the week "Monday"
$.fake.WeekDayShort Day of the week abbreviated "Mon"

Examples:

{
  "response": {
    "payload": {
      "createdAt": "$.fake.RFC3339",
      "birthDate": "$.fake.PastDate",
      "expiryDate": "$.fake.FutureDate",
      "timestamp": "$.fake.UnixTime",
      "dateComponents": {
        "year": "$.fake.Year",
        "month": "$.fake.Month",
        "day": "$.fake.Day",
        "weekday": "$.fake.WeekDay"
      }
    }
  }
}

Numeric Data

Number Generators

Function Description Example
$.fake.Float64 Floating-point number 123.456
$.fake.Float64(min, max) Float in range $.fake.Float64(10.0, 100.0)
$.fake.Price Price 99.99
$.fake.Latitude Latitude 40.7128
$.fake.Longitude Longitude -74.0060

Mathematical functions:

Function Description Example
$.fake.Digit Single digit 7
$.fake.RandomDigit Random digit 3
$.fake.NumberBetween(min, max) Number between values 75

Examples:

{
  "response": {
    "payload": {
      "price": "$.fake.Price",
      "weight": "$.fake.Float64(0.1, 999.9)",
      "coordinates": {
        "lat": "$.fake.Latitude",
        "lng": "$.fake.Longitude"
      },
      "ratings": {
        "overall": "$.fake.Float64(1.0, 5.0)",
        "count": "$.fake.IntBetween(1, 1000)"
      }
    }
  }
}

Addresses and Locations

Address Data

Function Description Example
$.fake.Address Full address "123 Main St, New York, NY 10001"
$.fake.Street Street name "Main Street"
$.fake.StreetAddress Street address "123 Main St"
$.fake.City City "New York"
$.fake.State State/region "California"
$.fake.StateAbbr State abbreviation "CA"
$.fake.Zip Postal code "90210"
$.fake.Country Country "United States"
$.fake.CountryAbbr Country code "US"

Examples:

{
  "response": {
    "payload": {
      "shippingAddress": {
        "street": "$.fake.StreetAddress",
        "city": "$.fake.City",
        "state": "$.fake.State",
        "zip": "$.fake.Zip",
        "country": "$.fake.Country"
      },
      "billingAddress": {
        "fullAddress": "$.fake.Address",
        "countryCode": "$.fake.CountryAbbr"
      }
    }
  }
}

Internet and Communication

Internet Data

Function Description Example
$.fake.Email Email address "john.doe@example.com"
$.fake.SafeEmail Safe email "user@example.org"
$.fake.FreeEmail Free email "user@gmail.com"
$.fake.CompanyEmail Corporate email "user@company.com"
$.fake.URL URL address "https://example.com/path"
$.fake.DomainName Domain name "example.com"
$.fake.IPv4 IPv4 address "192.168.1.1"
$.fake.IPv6 IPv6 address "2001:0db8:85a3::8a2e:0370:7334"
$.fake.MacAddress MAC address "00:1B:63:84:45:E6"
$.fake.UserAgent User Agent "Mozilla/5.0 (Windows NT 10.0; Win64; x64)..."

Communication and Telephony

Function Description Example
$.fake.Phone Phone number "+1-555-123-4567"
$.fake.PhoneFormatted Formatted phone number "(555) 123-4567"
$.fake.TollFreePhone Toll-free number "1-800-555-0199"

Examples:

{
  "response": {
    "payload": {
      "contact": {
        "email": "$.fake.Email",
        "phone": "$.fake.Phone",
        "website": "$.fake.URL"
      },
      "technical": {
        "ipAddress": "$.fake.IPv4",
        "macAddress": "$.fake.MacAddress",
        "userAgent": "$.fake.UserAgent"
      }
    }
  }
}

Business Data

Corporate Information

Function Description Example
$.fake.Company Company name "Acme Corporation"
$.fake.CompanySlogan Company slogan "Innovation at its best"
$.fake.JobTitle Job title "Senior Software Engineer"
$.fake.Department Department "Engineering"
$.fake.Industry Industry "Technology"

Financial Data

Function Description Example
$.fake.CreditCard Credit card number "4111111111111111"
$.fake.CreditCardType Card type "Visa"
$.fake.Currency Currency code "USD"
$.fake.CurrencySymbol Currency symbol "$"
$.fake.BTC Bitcoin address "1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa"

E-commerce Data

Function Description Example
$.fake.ProductName Product name "Wireless Bluetooth Headphones"
$.fake.ProductCategory Product category "Electronics"
$.fake.Color Color "Blue"
$.fake.HexColor HEX color "#FF5733"
$.fake.RGB RGB color "rgb(255, 87, 51)"

Examples:

{
  "response": {
    "payload": {
      "company": {
        "name": "$.fake.Company",
        "slogan": "$.fake.CompanySlogan",
        "industry": "$.fake.Industry"
      },
      "employee": {
        "jobTitle": "$.fake.JobTitle",
        "department": "$.fake.Department"
      },
      "product": {
        "name": "$.fake.ProductName",
        "category": "$.fake.ProductCategory",
        "color": "$.fake.Color",
        "price": "$.fake.Price"
      },
      "payment": {
        "cardNumber": "$.fake.CreditCard",
        "cardType": "$.fake.CreditCardType",
        "currency": "$.fake.Currency"
      }
    }
  }
}

Localized Data

Russian Data

Function Description Example
$.fake.RussianFirstNameMale Russian male first name "Aleksandr"
$.fake.RussianFirstNameFemale Russian female first name "Anna"
$.fake.RussianLastNameMale Russian male last name "Ivanov"
$.fake.RussianLastNameFemale Russian female last name "Ivanova"
$.fake.RussianCity Russian city "Moskva"
$.fake.RussianRegion Russian region "Moskovskaya oblast"

Chinese Data

Function Description Example
$.fake.ChineseFirstName Chinese first name "Wei"
$.fake.ChineseLastName Chinese last name "Li"
$.fake.ChineseName Chinese full name "Li Wei"

German Data

Function Description Example
$.fake.GermanFirstName German first name "Hans"
$.fake.GermanLastName German last name "Mueller"

Examples:

{
  "response": {
    "payload": {
      "users": [
        {
          "locale": "ru",
          "firstName": "$.fake.RussianFirstNameMale",
          "lastName": "$.fake.RussianLastNameMale",
          "city": "$.fake.RussianCity"
        },
        {
          "locale": "cn",
          "firstName": "$.fake.ChineseFirstName",
          "lastName": "$.fake.ChineseLastName",
          "fullName": "$.fake.ChineseName"
        },
        {
          "locale": "de",
          "firstName": "$.fake.GermanFirstName",
          "lastName": "$.fake.GermanLastName"
        }
      ]
    }
  }
}

Special Functions

Multimedia

Function Description Example
$.fake.ImageURL Image URL "https://picsum.photos/640/480"
$.fake.ImageURL(width, height) Image with dimensions "https://picsum.photos/800/600"
$.fake.AvatarURL User avatar "https://i.pravatar.cc/150"
$.fake.LoremPixel Lorem Pixel image "http://lorempixel.com/640/480/"

Security

Function Description Example
$.fake.Password Password "Tr@nsf0rm3r!"
$.fake.MD5 MD5 hash "5d41402abc4b2a76b9719d911017c592"
$.fake.SHA1 SHA1 hash "aaf4c61ddcc5e8a2dabede0f3b482cd9aea9434d"
$.fake.SHA256 SHA256 hash "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"
$.fake.JWT JSON Web Token "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9..."

Codes and Standards

Function Description Example
$.fake.ISBN10 ISBN-10 code "0123456789"
$.fake.ISBN13 ISBN-13 code "9780123456789"
$.fake.EAN8 EAN-8 barcode "12345670"
$.fake.EAN13 EAN-13 barcode "1234567890128"
$.fake.IBAN IBAN number "GB82WEST12345698765432"

Examples:

{
  "response": {
    "payload": {
      "media": {
        "avatar": "$.fake.AvatarURL",
        "thumbnail": "$.fake.ImageURL(200, 200)",
        "banner": "$.fake.ImageURL(1200, 300)"
      },
      "security": {
        "token": "$.fake.JWT",
        "passwordHash": "$.fake.SHA256",
        "sessionId": "$.fake.MD5"
      },
      "product": {
        "isbn": "$.fake.ISBN13",
        "barcode": "$.fake.EAN13",
        "sku": "SKU-$.fake.UUIDDigit"
      }
    }
  }
}

Practical Examples

Complete User Profile

{
  "id": "user-profile-complete",
  "http": {
    "route": "/api/users/profile"
  },
  "response": {
    "payload": {
      "user": {
        "id": "$.fake.UUID",
        "username": "$.fake.Username",
        "profile": {
          "firstName": "$.fake.FirstName",
          "lastName": "$.fake.LastName",
          "fullName": "$.fake.Name",
          "avatar": "$.fake.AvatarURL",
          "birthDate": "$.fake.PastDate",
          "gender": "$.fake.Gender"
        },
        "contact": {
          "email": "$.fake.Email",
          "phone": "$.fake.Phone",
          "website": "$.fake.URL"
        },
        "address": {
          "street": "$.fake.StreetAddress",
          "city": "$.fake.City",
          "state": "$.fake.State",
          "zip": "$.fake.Zip",
          "country": "$.fake.Country",
          "coordinates": {
            "lat": "$.fake.Latitude",
            "lng": "$.fake.Longitude"
          }
        },
        "work": {
          "company": "$.fake.Company",
          "jobTitle": "$.fake.JobTitle",
          "department": "$.fake.Department",
          "industry": "$.fake.Industry"
        },
        "preferences": {
          "language": "en",
          "timezone": "UTC",
          "theme": "dark",
          "notifications": "$.fake.Bool"
        },
        "metadata": {
          "createdAt": "$.fake.RFC3339",
          "lastLoginAt": "$.fake.RFC3339",
          "ipAddress": "$.fake.IPv4",
          "userAgent": "$.fake.UserAgent"
        }
      }
    }
  }
}

E-commerce Product

{
  "id": "ecommerce-product",
  "http": {
    "route": "/api/products/:id"
  },
  "response": {
    "payload": {
      "product": {
        "id": "$.fake.UUIDDigit",
        "sku": "PRD-$.fake.UUIDDigit",
        "name": "$.fake.ProductName",
        "description": "$.fake.Paragraph",
        "category": "$.fake.ProductCategory",
        "pricing": {
          "price": "$.fake.Price",
          "currency": "$.fake.Currency",
          "currencySymbol": "$.fake.CurrencySymbol",
          "originalPrice": "$.fake.Float64($.fake.Price * 1.1, $.fake.Price * 1.5)",
          "discount": "$.fake.IntBetween(5, 50)"
        },
        "inventory": {
          "inStock": "$.fake.Bool",
          "quantity": "$.fake.IntBetween(0, 1000)",
          "reserved": "$.fake.IntBetween(0, 100)"
        },
        "attributes": {
          "color": "$.fake.Color",
          "hexColor": "$.fake.HexColor",
          "weight": "$.fake.Float64(0.1, 50.0)",
          "dimensions": {
            "length": "$.fake.Float64(1.0, 100.0)",
            "width": "$.fake.Float64(1.0, 100.0)",
            "height": "$.fake.Float64(1.0, 100.0)"
          }
        },
        "media": {
          "images": [
            "$.fake.ImageURL(800, 600)",
            "$.fake.ImageURL(800, 600)",
            "$.fake.ImageURL(800, 600)"
          ],
          "thumbnail": "$.fake.ImageURL(200, 200)",
          "video": "$.fake.URL"
        },
        "ratings": {
          "average": "$.fake.Float64(1.0, 5.0)",
          "count": "$.fake.IntBetween(0, 10000)",
          "distribution": {
            "5star": "$.fake.IntBetween(0, 1000)",
            "4star": "$.fake.IntBetween(0, 800)",
            "3star": "$.fake.IntBetween(0, 500)",
            "2star": "$.fake.IntBetween(0, 200)",
            "1star": "$.fake.IntBetween(0, 100)"
          }
        },
        "shipping": {
          "freeShipping": "$.fake.Bool",
          "weight": "$.fake.Float64(0.1, 10.0)",
          "dimensions": "$.fake.Float64(1.0, 50.0) x $.fake.Float64(1.0, 50.0) x $.fake.Float64(1.0, 50.0)",
          "estimatedDelivery": "$.fake.FutureDate"
        },
        "metadata": {
          "createdAt": "$.fake.RFC3339",
          "updatedAt": "$.fake.RFC3339",
          "vendor": "$.fake.Company",
          "vendorId": "$.fake.UUIDDigit",
          "barcode": "$.fake.EAN13",
          "isbn": "$.fake.ISBN13"
        }
      }
    }
  }
}

Financial Data

{
  "id": "financial-transaction",
  "http": {
    "route": "/api/transactions"
  },
  "response": {
    "payload": {
      "transaction": {
        "id": "$.fake.UUID",
        "type": "payment",
        "status": "completed",
        "amount": {
          "value": "$.fake.Price",
          "currency": "$.fake.Currency",
          "symbol": "$.fake.CurrencySymbol"
        },
        "fees": {
          "processingFee": "$.fake.Float64(0.99, 9.99)",
          "serviceFee": "$.fake.Float64(0.50, 5.00)"
        },
        "payment": {
          "method": "credit_card",
          "card": {
            "number": "$.fake.CreditCard",
            "type": "$.fake.CreditCardType",
            "lastFour": "1234",
            "expiryMonth": "$.fake.IntBetween(1, 12)",
            "expiryYear": "$.fake.IntBetween(2024, 2030)"
          }
        },
        "merchant": {
          "id": "$.fake.UUIDDigit",
          "name": "$.fake.Company",
          "category": "$.fake.ProductCategory",
          "address": "$.fake.Address"
        },
        "customer": {
          "id": "$.fake.UUID",
          "email": "$.fake.Email",
          "name": "$.fake.Name",
          "phone": "$.fake.Phone"
        },
        "timestamps": {
          "createdAt": "$.fake.RFC3339",
          "processedAt": "$.fake.RFC3339",
          "completedAt": "$.fake.RFC3339"
        },
        "security": {
          "transactionHash": "$.fake.SHA256",
          "authorizationCode": "$.fake.MD5",
          "riskScore": "$.fake.Float64(0.0, 100.0)"
        }
      }
    }
  }
}

Best Practices

Recommendations

  1. Use appropriate data types:

    "userId": "$.fake.UUID",              // For IDs
"age": "$.fake.IntBetween(18, 80)",   // For age
"email": "$.fake.Email"               // For email

  2. Combine Faker with real data:

    "displayName": "User $.fake.FirstName",
"fullAddress": "$.fake.Address, Apt $.fake.IntBetween(1, 999)"

  3. Use realistic ranges:

    "price": "$.fake.Float64(9.99, 999.99)",    // Realistic price
"rating": "$.fake.Float64(1.0, 5.0)",       // Rating from 1 to 5
"percentage": "$.fake.Float64(0.0, 100.0)"  // Percentage from 0 to 100

  4. Structure complex objects:

    "user": {
  "personal": {
    "firstName": "$.fake.FirstName",
    "lastName": "$.fake.LastName"
  },
  "contact": {
    "email": "$.fake.Email",
    "phone": "$.fake.Phone"
  }
}

What to Avoid

  1. Do not use unrealistic ranges:

    "age": "$.fake.IntBetween(1, 1000)"      // Unrealistic
"price": "$.fake.Float64(-100, 1000000)" // Negative price

  2. Do not mix data types without logic:

    "id": "$.fake.FirstName"                 // Name as ID
"email": "$.fake.Int"                    // Number as email

Use Faker to create realistic and diverse test data!

See Also

  • JsonPath Guide – query language used together with Faker for dynamic responses
  • Store Systems – persist Faker-generated data across mock invocations
  • API Reference – complete REST API for creating mocks with Faker
  • Web UI Guide – create mocks with Faker visually in the Constructor
  • Quick Start – get started with your first Faker-powered mock
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