faker

You can also add your own generator function to your own defined tags.

package main

import (
	"fmt"
	"reflect"

	"github.com/cloudquery/faker/v3"
)

// Gondoruwo ...
type Gondoruwo struct {
	Name       string
	Locatadata int
}

// custom type that aliases over slice of byte
type CustomUUID []byte

// Sample ...
type Sample struct {
	ID        int64      `faker:"customIdFaker"`
	Gondoruwo Gondoruwo  `faker:"gondoruwo"`
	Danger    string     `faker:"danger"`
	UUID      CustomUUID `faker:"customUUID"`
}

// CustomGenerator ...
func CustomGenerator() {
	_ = faker.AddProvider("customIdFaker", func(v reflect.Value) (interface{}, error) {
		return int64(43), nil
	})
	_ = faker.AddProvider("danger", func(v reflect.Value) (interface{}, error) {
		return "danger-ranger", nil
	})

	_ = faker.AddProvider("gondoruwo", func(v reflect.Value) (interface{}, error) {
		obj := Gondoruwo{
			Name:       "Power",
			Locatadata: 324,
		}
		return obj, nil
	})

	_ = faker.AddProvider("customUUID", func(v reflect.Value) (interface{}, error) {
		s := CustomUUID{
			0, 8, 7, 2, 3,
		}
		return s, nil
	})
}

// You can also add your own generator function to your own defined tags.
func main() {
	CustomGenerator()
	var sample Sample
	_ = faker.FakeData(&sample)
	fmt.Printf("%+v", sample)
}

Output:

{ID:43 Gondoruwo:{Name:Power Locatadata:324} Danger:danger-ranger UUID:[0 8 7 2 3]}

Single fake function can be used for retrieving particular values.

// Address
faker.Latitude()  // => 81.12195
faker.Longitude() // => -84.38158

// Datetime
faker.UnixTime()   // => 1197930901
faker.Date()       // => 1982-02-27
faker.TimeString() // => 03:10:25
faker.MonthName()  // => February
faker.YearString() // => 1994
faker.DayOfWeek()  // => Sunday
faker.DayOfMonth() // => 20
faker.Timestamp()  // => 1973-06-21 14:50:46
faker.Century()    // => IV
faker.Timezone()   // => Asia/Jakarta
faker.Timeperiod() // => PM

// Internet
faker.Email()      // => mJBJtbv@OSAaT.com
faker.MacAddress() // => cd:65:e1:d4:76:c6
faker.DomainName() // => FWZcaRE.org
faker.URL()        // => https://www.oEuqqAY.org/QgqfOhd
faker.Username()   // => lVxELHS
faker.IPv4()       // => 99.23.42.63
faker.IPv6()       // => 975c:fb2c:2133:fbdd:beda:282e:1e0a:ec7d
faker.Password()   // => dfJdyHGuVkHBgnHLQQgpINApynzexnRpgIKBpiIjpTP

// Words and Sentences
faker.Word()      // => nesciunt
faker.Sentence()  // => Consequatur perferendis voluptatem accusantium.
faker.Paragraph() // => Aut consequatur sit perferendis accusantium voluptatem. Accusantium perferendis consequatur voluptatem sit aut. Aut sit accusantium consequatur voluptatem perferendis. Perferendis voluptatem aut accusantium consequatur sit.

// Payment
faker.CCType()             // => American Express
faker.CCNumber()           // => 373641309057568
faker.Currency()           // => USD
faker.AmountWithCurrency() // => USD 49257.100

// Person
faker.TitleMale()       // => Mr.
faker.TitleFemale()     // => Mrs.
faker.FirstName()       // => Whitney
faker.FirstNameMale()   // => Kenny
faker.FirstNameFemale() // => Jana
faker.LastName()        // => Rohan
faker.Name()            // => Mrs. Casandra Kiehn

// Phone
faker.Phonenumber()         // -> 201-886-0269
faker.TollFreePhoneNumber() // => (777) 831-964572
faker.E164PhoneNumber()     // => +724891571063

//  UUID
faker.UUIDHyphenated() // => 8f8e4463-9560-4a38-9b0c-ef24481e4e27
faker.UUIDDigit()      // => 90ea6479fd0e4940af741f0a87596b73

// Unique values
faker.SetGenerateUniqueValues(true) // Enable unique data generation on single fake data functions
faker.Word()
// ...
faker.SetGenerateUniqueValues(false) // Disable unique data generation on single fake data functions
faker.ResetUnique()                  // Forget all generated unique values

package main

import (
	"fmt"

	"github.com/cloudquery/faker/v3"
)

// SomeStructWithTags ...
type SomeStructWithTags struct {
	Latitude           float32 `faker:"lat"`
	Longitude          float32 `faker:"long"`
	CreditCardNumber   string  `faker:"cc_number"`
	CreditCardType     string  `faker:"cc_type"`
	Email              string  `faker:"email"`
	DomainName         string  `faker:"domain_name"`
	IPV4               string  `faker:"ipv4"`
	IPV6               string  `faker:"ipv6"`
	Password           string  `faker:"password"`
	Jwt                string  `faker:"jwt"`
	PhoneNumber        string  `faker:"phone_number"`
	MacAddress         string  `faker:"mac_address"`
	URL                string  `faker:"url"`
	UserName           string  `faker:"username"`
	TollFreeNumber     string  `faker:"toll_free_number"`
	E164PhoneNumber    string  `faker:"e_164_phone_number"`
	TitleMale          string  `faker:"title_male"`
	TitleFemale        string  `faker:"title_female"`
	FirstName          string  `faker:"first_name"`
	FirstNameMale      string  `faker:"first_name_male"`
	FirstNameFemale    string  `faker:"first_name_female"`
	LastName           string  `faker:"last_name"`
	Name               string  `faker:"name"`
	UnixTime           int64   `faker:"unix_time"`
	Date               string  `faker:"date"`
	Time               string  `faker:"time"`
	MonthName          string  `faker:"month_name"`
	Year               string  `faker:"year"`
	DayOfWeek          string  `faker:"day_of_week"`
	DayOfMonth         string  `faker:"day_of_month"`
	Timestamp          string  `faker:"timestamp"`
	Century            string  `faker:"century"`
	TimeZone           string  `faker:"timezone"`
	TimePeriod         string  `faker:"time_period"`
	Word               string  `faker:"word"`
	Sentence           string  `faker:"sentence"`
	Paragraph          string  `faker:"paragraph"`
	Currency           string  `faker:"currency"`
	Amount             float64 `faker:"amount"`
	AmountWithCurrency string  `faker:"amount_with_currency"`
	UUIDHypenated      string  `faker:"uuid_hyphenated"`
	UUID               string  `faker:"uuid_digit"`
	Skip               string  `faker:"-"`
	PaymentMethod      string  `faker:"oneof: cc, paypal, check, money order"` // oneof will randomly pick one of the comma-separated values supplied in the tag
	AccountID          int     `faker:"oneof: 15, 27, 61"`                     // use commas to separate the values for now. Future support for other separator characters may be added
	Price32            float32 `faker:"oneof: 4.95, 9.99, 31997.97"`
	Price64            float64 `faker:"oneof: 47463.9463525, 993747.95662529, 11131997.978767990"`
	NumS64             int64   `faker:"oneof: 1, 2"`
	NumS32             int32   `faker:"oneof: -3, 4"`
	NumS16             int16   `faker:"oneof: -5, 6"`
	NumS8              int8    `faker:"oneof: 7, -8"`
	NumU64             uint64  `faker:"oneof: 9, 10"`
	NumU32             uint32  `faker:"oneof: 11, 12"`
	NumU16             uint16  `faker:"oneof: 13, 14"`
	NumU8              uint8   `faker:"oneof: 15, 16"`
	NumU               uint    `faker:"oneof: 17, 18"`
}

func main() {

	a := SomeStructWithTags{}
	err := faker.FakeData(&a)
	if err != nil {
		fmt.Println(err)
	}
	fmt.Printf("%+v", a)
	/*
		Result:
		{
			Latitude: 81.12195
			Longitude: -84.38158
			CreditCardType: American Express
			CreditCardNumber: 373641309057568
			Email: mJBJtbv@OSAaT.ru
			DomainName: FWZcaRE.ru,
			IPV4: 99.23.42.63
			IPV6: 975c:fb2c:2133:fbdd:beda:282e:1e0a:ec7d
			Password: dfJdyHGuVkHBgnHLQQgpINApynzexnRpgIKBpiIjpTPOmNyMFb
			Jwt: HDMNSOKhEIYkPIuHcVjfCtHlKkaqLGrUEqjKVkgR.HDMNSOKhEIYkPIuHcVjfCtHlKkaqLGrUEqjKVkgR.HDMNSOKhEIYkPIuHcVjfCtHlKkaqLGrUEqjKVkgR
			PhoneNumber: 792-153-4861
			MacAddress: cd:65:e1:d4:76:c6
			URL: https://www.oEuqqAY.org/QgqfOhd
			UserName: lVxELHS
			TollFreeNumber: (777) 831-964572
			E164PhoneNumber: +724891571063
			TitleMale: Mr.
			TitleFemale: Queen
			FirstName: Whitney
			FirstNameMale: Kenny
			FirstNameFemale: Jana
			LastName: Rohan
			Name: Miss Casandra Kiehn
			UnixTime: 1197930901
			Date: 1982-02-27
			Time: 03:10:25
			MonthName: February
			Year: 1996
			DayOfWeek: Sunday
			DayOfMonth: 20
			Timestamp: 1973-06-21 14:50:46
			Century: IV
			TimeZone: Canada/Eastern
			TimePeriod: AM
			Word: nesciunt
			Sentence: Consequatur perferendis aut sit voluptatem accusantium.
			Paragraph: Aut consequatur sit perferendis accusantium voluptatem. Accusantium perferendis consequatur voluptatem sit aut. Aut sit accusantium consequatur voluptatem perferendis. Perferendis voluptatem aut accusantium consequatur sit.
			Currency: IRR,
			Amount: 88.990000,
			AmountWithCurrency: XBB 49257.100000,
			UUIDHypenated: 8f8e4463-9560-4a38-9b0c-ef24481e4e27,
			UUID: 90ea6479fd0e4940af741f0a87596b73,
			PaymentMethod: paypal,
			AccountID: 61,
			Price32: 4.95,
			Price64: 993747.95662529
			NumS64:	1
			NumS32:	-3
			NumS16:	5
			NumS8:	-8
			NumU64:	9
			NumU32:	11
			NumU16:	13
			NumU8:	15
			NumU:	17
			Skip:
		}
	*/

}

package main

import (
	"fmt"

	"github.com/cloudquery/faker/v3"
)

// SomeStructWithUnique ...
type SomeStructWithUnique struct {
	Word string `faker:"word,unique"`
}

func main() {
	for i := 0; i < 5; i++ { // Generate 5 structs having a unique word
		a := SomeStructWithUnique{}
		err := faker.FakeData(&a)
		if err != nil {
			fmt.Println(err)
		}
		fmt.Printf("%+v", a)
	}
	faker.ResetUnique() // Forget all generated unique values. Allows to start generating another unrelated dataset.

	// Result:
	//	{Word:nobis}{Word:recusandae}{Word:praesentium}{Word:doloremque}{Word:non}
}

You can set length for your random strings also set boundary for your integers.

// SomeStruct ...
type SomeStruct struct {
	StringENG string `faker:"lang=eng"`
	StringCHI string `faker:"lang=chi"`
	StringRUS string `faker:"lang=rus"`
}

a := SomeStruct{}
_ = faker.SetRandomStringLength(5)
_ = faker.FakeData(&a)
fmt.Printf("%+v", a)
// Result:
/*
	   {
		   StringENG:VVcaPS
		   StringCHI: 随机字符串
		   StringRUS:ваЩфз
	   }
*/

You can set length for your random strings also set boundary for your integers.

// SomeStruct ...
type SomeStruct struct {
	Inta  int   `faker:"boundary_start=5, boundary_end=10"`
	Int8  int8  `faker:"boundary_start=100, boundary_end=1000"`
	Int16 int16 `faker:"boundary_start=123, boundary_end=1123"`
	Int32 int32 `faker:"boundary_start=-10, boundary_end=8123"`
	Int64 int64 `faker:"boundary_start=31, boundary_end=88"`

	UInta  uint   `faker:"boundary_start=35, boundary_end=152"`
	UInt8  uint8  `faker:"boundary_start=5, boundary_end=1425"`
	UInt16 uint16 `faker:"boundary_start=245, boundary_end=2125"`
	UInt32 uint32 `faker:"boundary_start=0, boundary_end=40"`
	UInt64 uint64 `faker:"boundary_start=14, boundary_end=50"`

	ASString []string          `faker:"len=50"`
	SString  string            `faker:"len=25"`
	MSString map[string]string `faker:"len=30"`
	MIint    map[int]int       `faker:"boundary_start=5, boundary_end=10"`
}

_ = faker.SetRandomMapAndSliceSize(20) // Random generated map or array size wont exceed 20...
a := SomeStruct{}
_ = faker.FakeData(&a)
fmt.Printf("%+v", a)
// Result:
/*
   {
       Inta:7
       Int8:-102
       Int16:556
       Int32:113
       Int64:70
       UInta:78
       UInt8:54
       UInt16:1797
       UInt32:8
       UInt64:34
       ASString:[
           geHYIpEoQhQdijFooVEAOyvtTwJOofbQPJdbHvEEdjueZaKIgI
           WVJBBtmrrVccyIydAiLSkMwWbFzFMEotEXsyUXqcmBTVORlkJK
           xYiRTRSZRuGDcMWYoPALVMZgIXoTQtmdGXQfbISKJiavLspuBV
           qsoiYlyRbXLDAMoIdQhgMriODYWCTEYepmjaldWLLjkulDGuQN
           GQXUlqNkVjPKodMebPIeoZZlxfhbQJOjHSRjUTrcgBFPeDZIxn
           MEeRkkLceDsqKLEJFEjJxHtYrYxQMxYcuRHEDGYSPbELDQLSsj
           tWUIACjQWeiUhbboGuuEQIhUJCRSBzVImpYwOlFbsjCRmxboZW
           ZDaAUZEgFKbMJoKIMpymTreeZGWLXNCfVzaEyWNdbkaZOcsfst
           uwlsZBMlEknIBsALpXRaplZWVtXTKzsWglRVBpmfsQfqraiEYA
           AXszbzsOzYPYeXHXRwoPmoPoBxopdFFvWMBTPCxESTepRpjlnB
           kTuOPHlUrSzUQRmZMYplWbyoBbWzQYCiydyzurOduhjuyiGrCE
           FZbeLMbelIeCMnixknIARZRbwALObGXADQqianJbkiEAqqpdnK
           TiQrZbnkvxEciyKXlliUDOGVdpMoAsHSalFbLcYyXxNFLAhqjy
           KlbjbloxkWKSqvUfJQPpFLoddWgeABfYUoaAnylKmEHwxgNsnO
           ]
       SString:VVcaPSFrOPYlEkpVyTRbSZneB
       MSString:map[
           ueFBFTTmqDwrXDoXAYTRhQRmLXhudA:AhQewvZfrlytbAROzGjpXUmNQzIoGl
           fZwrCsFfZwqMsDJXOUYIacflFIeyFU:VMufFCRRHTtuFthOrRAMbzbKVJHnvJ
           rHDQTyZqZVSPLwTtZfNSwKWrgmRghL:lRSXNHkhUyjDuBgoAfrQwOcHYilqRB
           BvCpQJMHzKXKbOoAnTXkLCNxKshwWr:tiNFrXAXUtdywkyygWBrEVrmAcAepD
           uWWKgHKTkUgAZiopAIUmgVWrkrceVy:GuuDNTUiaBtOKwWrMoZDiyaOPxywnq
           HohMjOdMDkAqimKPTgdjUorydpKkly:whAjmraukcZczskqycoJELlMJTghca
           umEgMBGUvBptdKImKsoWXMGJJoRbgT:tPpgHgLEyHmDOocOiSgTbXQHVduLxP
           SRQLHjBXCXKvbLIktdKeLwMnIFOmbi:IJBpLyTcraOxOUtwSKTisjElpulkTL
           dbnDeJZLqMXQGjbTSNxPSlfDHGCghU:JWrymovFwNWbIQBxPpQmlgJsgpXcui
           roraKNGnBXnrJlsxTnFgxHyZeTXdAC:XIcLWqUAQAbfkRrgfjrTVxZCvRJXyl
           TrvxqVVjXAboYDPvUglSJQrltPjzLx:nBhWdfNPybnNnCyQlSshWKOnwUMQzL
           dTHhWJWMwfVvKpIKTFCaoBJgKmnfbD:ixjNHsvSkRkFiNLpgUzIKPsheqhCeY
           lWyBrtfcGWiNbSTJZJXwOPvVngZZMk:kvlYeGgwguVtiafGKjHWsYWewbaXte
           bigsYNfVcNMGtnzgaqEjeRRlIcUdbR:hYOnJupEOvblTTEYzZYPuTVmvTmiit
           ]
       MIint:map[7:7 5:7 8:8 9:5 6:5]
   }
*/

You can set the size for your random slices.

// SomeStruct ...
type SomeStruct struct {
	EmptyList       []string `faker:"slice_len=0"`
	FixedStringList []string `faker:"slice_len=2"`
	FixedIntList    []int64  `faker:"slice_len=4"`
	RandomIntList   []int64
}

_ = faker.SetRandomMapAndSliceSize(20) // If no slice_len is set, this sets the max of the random size
a := SomeStruct{}
_ = faker.FakeData(&a)
fmt.Printf("%+v", a)
// Result:
/*
	   {
	       EmptyList:[]
	       FixedStringList:[
		           geHYIpEoQhQdijFooVEAOyvtTwJOofbQPJdbHvEEdjueZaKIgI
		           WVJBBtmrrVccyIydAiLSkMwWbFzFMEotEXsyUXqcmBTVORlkJK
		   ]
		   FixedIntList:[10,25,60,15]
	       RandomIntList:[5,16,134,6235,123,53,123] //Random len() with a max of 20
	   }
*/

You also can use faker to generate your structs data randomly without any tag. And it will fill the data based on its data-type.

package main

import (
	"fmt"

	"github.com/cloudquery/faker/v3"
)

// SomeStruct ...
type SomeStruct struct {
	Int      int
	Int8     int8
	Int16    int16
	Int32    int32
	Int64    int64
	String   string
	Bool     bool
	SString  []string
	SInt     []int
	SInt8    []int8
	SInt16   []int16
	SInt32   []int32
	SInt64   []int64
	SFloat32 []float32
	SFloat64 []float64
	SBool    []bool
	Struct   AStruct
}

// AStruct ...
type AStruct struct {
	Number        int64
	Height        int64
	AnotherStruct BStruct
}

// BStruct ...
type BStruct struct {
	Image string
}

// You also can use faker to generate your structs data randomly without any tag.
// And it will fill the data based on its data-type.
func main() {
	a := SomeStruct{}
	err := faker.FakeData(&a)
	if err != nil {
		fmt.Println(err)
	}
	fmt.Printf("%+v", a)
	/*
		Result:
		{
		    Int:5231564546548329
		    Int8:52
		    Int16:8
		    Int32:2046951236
		    Int64:1486554863682234423
		    String:ELIQhSfhHmWxyzRPOTNblEQsp
		    Bool:false
		    SString:[bzYwplRGUAXPwatnpVMWSYjep zmeuJVGHHgmIsuyWmLJnDmbTI FqtejCwoDyMBWatoykIzorCJZ]
		    SInt:[11661230973193 626062851427 12674621422454 5566279673347]
		    SInt8:[12 2 58 22 11 66 5 88]
		    SInt16:[29295225 8411281 69902706328]
		    SInt32:[60525685140 2733640366211 278043484637 5167734561481]
		    SInt64:[81684520429188374184 9917955420365482658170 996818723778286568 163646873275501565]
		    SFloat32:[0.556428 0.7692596 0.6779895 0.29171365 0.95445055]
		    SFloat64:[0.44829454895586585 0.5495675898536803 0.6584538253883265]
		    SBool:[true false true false true true false]
		    Struct:{
		        Number:1
		        Height:26
		        AnotherStruct:{
		            Image:RmmaaHkAkrWHldVbBNuQSKlRb
		        }
		    }
		}
	*/
}