com.philiprehberger:mask-kit
v0.2.5680 downloadsMIT
Data masking for sensitive values in logs and API responses
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implementation com.philiprehberger:mask-kitREADME
mask-kit
Data masking for sensitive values in logs and API responses.
Installation
Gradle (Kotlin DSL)
implementation("com.philiprehberger:mask-kit:0.2.4")
Maven
<dependency>
<groupId>com.philiprehberger</groupId>
<artifactId>mask-kit</artifactId>
<version>0.2.4</version>
</dependency>
Usage
import com.philiprehberger.maskkit.*
// Top-level masking functions
mask("1234567890") // "******7890"
mask("1234567890", keep = 2) // "********90"
maskEmail("john@example.com") // "j***@example.com"
maskPhone("+1-555-123-4567") // "***********4567"
maskCreditCard("4111111111111111") // "****-****-****-1111"
maskSsn("123-45-6789") // "***-**-6789"
maskIban("DE89370400440532016789") // "DE**************6789"
Custom Mask Character
Pass a MaskOptions instance to any masking function to change the mask character:
val opts = MaskOptions(maskChar = '#')
mask("1234567890", options = opts) // "######7890"
maskEmail("john@example.com", opts) // "j###@example.com"
maskCreditCard("4111111111111111", opts) // "####-####-####-1111"
maskSsn("123-45-6789", opts) // "###-##-6789"
MaskStrategy (Sealed Interface)
Use MaskStrategy for flexible, programmatic masking:
// Full masking
applyStrategy("secret", MaskStrategy.Full)
// "******"
// Partial masking with visible start and end
applyStrategy("1234567890", MaskStrategy.Partial(visibleStart = 2, visibleEnd = 4))
// "12****7890"
// Regex-based masking
applyStrategy("123-45-6789", MaskStrategy.Regex("(\\d{3})-(\\d{2})-(\\d{4})", "***-**-$3"))
// "***-**-6789"
Batch Masking
Mask specific fields in a map:
val data = mapOf("name" to "John", "email" to "john@example.com", "age" to 30)
val fieldMasks = mapOf(
"email" to MaskStrategy.Full,
"name" to MaskStrategy.Partial(visibleStart = 1, visibleEnd = 0),
)
val result = maskMap(data, fieldMasks)
// {name=J***, email=****************, age=30}
Mask specific fields in any object using reflection:
data class Person(val name: String, val email: String, val age: Int)
val person = Person("John", "john@example.com", 30)
val result = maskFields(person, setOf("email", "name"))
// {name=****, email=****************, age=30}
Annotation-Based Masking
data class User(
val name: String,
@Masked(strategy = MaskType.EMAIL)
val email: String,
@Masked(strategy = MaskType.SSN)
val ssn: String,
@Masked(strategy = MaskType.IBAN)
val iban: String,
@Masked(strategy = MaskType.FULL, maskChar = '#')
val secret: String,
)
val user = User("John", "john@example.com", "123-45-6789", "DE89370400440532016789", "topsecret")
println(user.maskedToString())
// User(name=John, email=j***@example.com, ssn=***-**-6789, iban=DE**************6789, secret=#########)
API
| Function / Type | Description |
|---|---|
mask(value, keep, options) | Masks all but the last keep characters |
maskEmail(email, options) | Masks email local part, preserving first character and domain |
maskPhone(phone, options) | Masks phone number, showing last 4 digits |
maskCreditCard(card, options) | Masks credit card, showing last 4 digits in grouped format |
maskSsn(ssn, options) | Masks SSN, showing last 4 digits in ***-**-NNNN format |
maskIban(iban, options) | Masks IBAN, preserving country code and last 4 characters |
maskMap(map, fieldMasks, options) | Masks specified fields in a map using given strategies |
maskFields(obj, fieldNames, options) | Masks specified fields in any object via reflection |
applyStrategy(value, strategy, options) | Applies a MaskStrategy to a value |
MaskOptions(maskChar) | Configuration for mask character (default *) |
MaskStrategy | Sealed interface: Full, Partial(visibleStart, visibleEnd), Regex(pattern, replacement) |
MaskType | Enum for annotations: PARTIAL, FULL, EMAIL, CREDIT_CARD, PHONE, SSN, IBAN |
@Masked(strategy, keep, maskChar) | Property annotation for automatic masking |
T.maskedToString() | Extension producing toString() with @Masked properties masked |
Development
./gradlew build
./gradlew test
Support
If you find this project useful: