Golang Masking Tool
Golang Masking Tool is a simple utility of creating a masker tool which you can use to mask sensitive information. You can use a variety of filters with custom masking types to assist you.
Inspired by two repositories -
Both libraries were solving similar usecase but didn't cover all use cases I was looking for. Zlog is a libray that focuses more on logging and its filterating features are not exposed to be used separately. While Golang Masker doesn't cover all data types. Hence it didn't solve my use-cases.
So I combined both of them to create this library and sharing the best of both them. Added some more uses cases too.
Getting Started
$ go get -u github.com/anu1097/golang-masking-tool
Usage
Basic Example
Create Masking Instance
var maskingInstance = NewMaskTool()
Filter Sensitive Data
By Specified Field
Default
type myRecord struct {
ID string
Phone string
}
record := myRecord{
ID: "userId",
Phone: "090-0000-0000",
}
maskTool := NewMaskTool(filter.FieldFilter("Phone"))
filteredData := maskTool.MaskDetails(record)
// fmt.Println(filteredData)
// {userId [filtered]}
Custom Mask Type
type myRecord struct {
ID string
Phone string
Url string
Email string
Name string
Address string
CreditCard string
}
record := myRecord{
ID: "userId",
Phone: "090-0000-0000",
Url: "http://admin:mysecretpassword@localhost:1234/uri",
Email: "[email protected]",
Name: "John Doe",
Address: "1 AB Road, Paradise",
CreditCard: "4444-4444-4444-4444",
}
maskTool := NewMaskTool(
filter.CustomFieldFilter("Phone", customMasker.MMobile),
filter.CustomFieldFilter("Email", customMasker.MEmail),
filter.CustomFieldFilter("Url", customMasker.MURL),
filter.CustomFieldFilter("Name", customMasker.MName),
filter.CustomFieldFilter("ID", customMasker.MID),
filter.CustomFieldFilter("Address", customMasker.MAddress),
filter.CustomFieldFilter("CreditCard", customMasker.MCreditCard),
)
filteredData := maskTool.MaskDetails(record)
// fmt.Println(filteredData)
// {userId**** 090-***0-0000 http://admin:xxxxx@localhost:1234/uri dum****@dummy.com J**n D**e 1 AB R****** 4444-4******44-4444}
By Specified Field-Prefix
Default
type myRecord struct {
ID string
SecurePhone string
}
record := myRecord{
ID: "userId",
SecurePhone: "090-0000-0000",
}
maskTool := NewMaskTool(filter.FieldPrefixFilter("Secure"))
filteredData := maskTool.MaskDetails(record)
// fmt.Println(filteredData)
// {userId [filtered]}
Custom
maskTool := NewMaskTool(filter.CustomFieldPrefixFilter("Secure", customMasker.MMobile))
filteredData := maskTool.MaskDetails(record)
// fmt.Println(filteredData)
// {userId 090-***0-0000}
By Specified Value
Default
const issuedToken = "abcd1234"
maskTool := NewMaskTool(filter.ValueFilter(issuedToken))
record := "Authorization: Bearer " + issuedToken
filteredData := maskTool.MaskDetails(record)
// fmt.Println(filteredData)
// Authorization: Bearer [filtered]
Custom Mask Type
const issuedToken = "abcd1234"
maskTool := NewMaskTool(filter.CustomValueFilter(issuedToken, customMasker.MPassword))
record := "Authorization: Bearer " + issuedToken
filteredData := maskTool.MaskDetails(record)
// fmt.Println(filteredData)
// Authorization: Bearer ************
By custom type
Default
type password string
type myRecord struct {
ID string
Password password
}
record := myRecord{
ID: "userId",
Password: "abcd1234",
}
maskTool := NewMaskTool(filter.CustomTypeFilter(password(""), customMasker.MPassword))
filteredData := maskTool.MaskDetails(record)
// fmt.Println(filteredData)
// {userId [filtered]}
Custom Mask Type
type password string
type myRecord struct {
ID string
Password password
}
record := myRecord{
ID: "userId",
Password: "abcd1234",
}
maskTool := NewMaskTool(filter.CustomTypeFilter(password(""), customMasker.MPassword))
filteredData := maskTool.MaskDetails(record)
// fmt.Println(filteredData)
// {userId ************}
By struct tag
Default
type myRecord struct {
ID string
EMail string `mask:"secret"` //Use secret for default filter
}
record := myRecord{
ID: "userId",
EMail: "[email protected]",
}
maskTool := NewMaskTool(filter.TagFilter())
filteredData := maskTool.MaskDetails(record)
// fmt.Println(filteredData)
// {userId [filtered]}
Custom Mask Type
type myRecord struct {
ID string
EMail string `mask:"email"`
Phone string `mask:"mobile"`
}
record := myRecord{
ID: "userId",
EMail: "[email protected]",
Phone: "9191919191",
}
maskTool := NewMaskTool(filter.TagFilter(customMasker.MEmail, customMasker.MMobile))
filteredData := maskTool.MaskDetails(record)
// fmt.Println(filteredData)
// {userId dum****@dummy.com 9191***191}
By Regex Pattern
Default Phone Filter
type myRecord struct {
ID string
Phone string
}
record := myRecord{
ID: "userId",
Phone: "090-0000-0000",
}
maskTool := NewMaskTool(filter.PhoneFilter())
filteredData := maskTool.MaskDetails(record)
// fmt.Println(filteredData)
// {userId [filtered]}
Custom Phone Filter
type myRecord struct {
ID string
Phone string
}
record := myRecord{
ID: "userId",
Phone: "090-0000-0000",
}
maskTool := NewMaskTool((filter.CustomPhoneFilter(customMasker.MMobile)))
filteredData := maskTool.MaskDetails(record)
// fmt.Println(filteredData)
//{userId 090-***0-0000}
Default Email Filter
type myRecord struct {
ID string
Email string
}
record := myRecord{
ID: "userId",
Email: "[email protected]",
}
maskTool := NewMaskTool(filter.EmailFilter())
filteredData := maskTool.MaskDetails(record)
// fmt.Println(filteredData)
// {userId [filtered]}
Custom Email Filter
type myRecord struct {
ID string
Email string
}
record := myRecord{
ID: "userId",
Email: "[email protected]",
}
maskTool := NewMaskTool(filter.EmailFilter())
filteredData := maskTool.MaskDetails(record)
// fmt.Println(filteredData)
// {userId dum****@dummy.com}
Custom Regex Filter
customRegex := "^https:\\/\\/(dummy-backend.)[0-9a-z]*.com\\b([-a-zA-Z0-9@:%_\\+.~#?&//=]*)$"
type myRecord struct {
ID string
Link string
}
record := myRecord{
ID: "userId",
Link: "https://dummy-backend.getsimpl.com/v2/random",
}
maskTool := NewMaskTool(filter.CustomRegexFilter(customRegex))
filteredData := maskTool.MaskDetails(record)
// fmt.Println(filteredData)
// {userId [filtered]}
Custom Regex Filter With Mask Type
type myRecord struct {
ID string
Link string
}
record := myRecord{
ID: "userId",
Link: "https://dummy-backend.getsimpl.com/v2/random",
}
maskTool := NewMaskTool(filter.CustomRegexFilterWithMType(customRegex, customMasker.MPassword))
filteredData := maskTool.MaskDetails(record)
// fmt.Println(filteredData)
// {userId ************}
By AllFields Filter
Default
type child struct {
Data string
}
s := "test"
type myStruct struct {
Func func() time.Time
Chan chan int
Bool bool
Bytes []byte
Strs []string
StrsPtr []*string
Interface interface{}
Child child
ChildPtr *child
Data string
}
data := &myStruct{
Func: time.Now,
Chan: make(chan int),
Bool: true,
Bytes: []byte("timeless"),
Strs: []string{"aa"},
StrsPtr: []*string{&s},
Interface: &s,
Child: child{Data: "x"},
ChildPtr: &child{Data: "y"},
Data: "data",
}
mask := NewMaskingInstance(
filter.AllFieldFilter(),
)
filteredData := mask.MaskDetails(data)
// fmt.Println(filteredData)
// {<nil> <nil> false [] [] [] <nil> {} 0x1400009b180 [filtered]}
With Custom Mask Type
mask := NewMaskingInstance(
filter.CustomAllFieldFilter(customMasker.MPassword),
)
filteredData := mask.MaskDetails(data)
// fmt.Println(filteredData)
// {<nil> <nil> false [] [] [] <nil> {} 0x1400009b180 ************}
Custom Mask Types
| Type | Const | Tag | Description |
|---|---|---|---|
| Name | MName | name | mask the second letter and the third letter |
| Password | MPassword | password | always return ************ |
| Address | MAddress | addr | keep first 6 letters, mask the rest |
| MEmail | keep domain and the first 3 letters | ||
| Mobile | MMobile | mobile | mask 3 digits from the 4'th digit |
| Telephone | MTelephone | tel | remove (, ), , - chart, and mask last 4 digits of telephone number, format to (??)????-???? |
| ID | MID | id | mask last 4 digits of ID number |
| CreditCard | MCreditCard | credit | mask 6 digits from the 7'th digit |
| Secret | MStruct | secret | Uses default filtered string. Use only with Struct Tag filter |
Customise Masking Tool
Update Default Filter
maskTool := NewMaskTool(filter.FieldFilter("Phone"))
maskTool.SetFilteredLabel("CustomFilterString")
// maskTool.GetFilteredLabel()
// CustomFilterString
Update Custom Masker Character
maskTool := NewMaskTool(filter.FieldFilter("Phone"))
maskTool.UpdateCustomMaskingChar(customMasker.PCross)
Append More Filter
maskTool := NewMaskTool(filter.FieldFilter("Phone"))
maskTool.AppendFilters(filter.EmailFilter())
License
- MIT License
- Author: Anurag Gupta [email protected]
