Fast Faker

FastFaker is a data generator written in go. It can generate over 50 data types and has 2 modes of operation: fast or (concurrent) safe.

Features

• Every function has an example and a benchmark, see benchmarks
• Zero dependencies (no external calls, no vendor, dep or modules required)
• Randomizes user defined structs
• Over 130 functions for regular use
• Templates with over 110 variables
• Extensible
• Concurrent safe
• Go 1.x compatibility
• Performance
• Idiomatic Go
• predefined popular structures (Address, Person ...)
• 200 unit tests and examples

130+ Functions!!!

If there is something that is generic enough missing from this package let me know!

How to use

Library

The package is meant to be used as a Go package, and imported in your own application, but it can be used as an app or service too:

Utility

A small example is provided as an example, and can be used as a binary standalone utility, after compilation:

$ go build -o fastfaker example/standalone-template/main.go
$ ./fastfaker '{name}'
$ Victoria Berge

Web service

If you do not want to spend time importing this library in your project, or you are using a different programming language, you can use the Pseudoservice microservice. It is a HTTP Web sever wrapper on the Templates functionality.

docker run --name pseudoservice -p 8080:8080 -d -e APIKEY=MYSECRET bgadrian/pseudoservice
curl "http://localhost:8080/custom/1?token=MYSECRET&template=~name~"
{"results":["Jefferey Koch"],"seed":-4329827746951412836}

Documentation

All the public functions have comments, examples, tests and benchmarks: https://godoc.org/github.com/bgadrian/fastfaker/faker

You can find more examples in the Example folder.

Example

	faker.Global.Name()             // Markus Moen
	faker.Global.Email()            // [email protected]
	faker.Global.Phone()            // (570)245-7485
	faker.Global.BS()               // front-end
	faker.Global.BeerName()         // Duvel
	faker.Global.Color()            // MediumOrchid
	faker.Global.Company()          // Moen, Pagac and Wuckert
	faker.Global.CreditCardNumber() // 4287271570245748
	faker.Global.HackerPhrase()     // Connecting the array won't do anything, we need to generate the haptic COM driver!
	faker.Global.JobTitle()         // Director
	faker.Global.PasswordFull()     // +eHQa02X9n3X
	faker.Global.CurrencyShort()    // USD
	// 130+ more!!!

	// Create structs with random injected data
	type Foo struct {
		Browser string `fake:"{browser}"`
		Name    string `fake:"{beername}"`
		Int     int
		Dice    uint8
		Pointer *int
		Skip    *string `fake:"skip"`
	}
	var f Foo
	faker.Global.Struct(&f)
	fmt.Printf("%s\n", f.Browser)  //firefox
	fmt.Printf("%s\n", f.Name)     //Samuel Smith’s Oatmeal Stout
	fmt.Printf("%d\n", f.Int)      //-3651589698752897048
	fmt.Printf("%d\n", f.Dice)     //62
	fmt.Printf("%d\n", *f.Pointer) //-8819218091111228151
	fmt.Printf("%v\n", f.Skip)     //<nil>

Faker types, concurrency and performance

Fast Faker has 2 modes of operating: safe or fast.

Safe

faker.Global and instances of NewSafeFaker() are safe to be used from multiple goroutines, but has a small overhead. Similar with rand.* global functions it uses a mutex.

Advantage: easy to use, safe.

Fast

Another way of using faker is having one Faker instance for each goroutine.

go func(){
    myOwnFaker := faker.NewFastFaker()
    
    myOwnFaker.Name() // Markus Moen
    myOwnFaker.Email() // [email protected]
}()

Advantage: performance

For a heavy usage in a 4 CPU env, the performance benefits of the FastFaker can be up to 10x:

go test -benchmem  -bench=BenchmarkNew* github.com/bgadrian/fastfaker/faker
goos: linux
goarch: amd64
pkg: github.com/bgadrian/fastfaker/faker
BenchmarkNewSafeFaker_Parallel-4          500000              2668 ns/op               0 B/op          0 allocs/op
BenchmarkNewFastFaker_Parallel-4        10000000               225 ns/op               0 B/op          0 allocs/op

Templates

Template is the most powerful FastFaker feature. It allows custom patterns/templates (JSON, YAML, HTML, ...) of text to be filled with over 110 random types of data (variables).

It can be used directly (faker.Template* methods) or via the faker.Struct fill method and fake: tags.

//instead of:
fmt.Sprintf("I'm %s, call me at %s!", fastFaker.Name(), fastFaker.Numerify("###-###-####"))
//you can do:
fastFaker.Template("I'm {name}, call me at ###-###-####!") // I'm John, call me at 152-335-8761!

You can use any type of texts, formats, encoded or not (HTML, JSON, YAML, configs ...). For more details see the TEMPLATES section

/Data

If you want to use the raw data that the Faker uses internally (like Names, Streets, Countries and Companies) you can import the Data package directly, see its documentation.

/Randomizer

The pseudo-data generator has its own package. At its core it is a rand.* wrapper with more functions.

gofakeit

This library started as a fork of gofakeit, but I had different requirements from such a library, in particular performance and extensibility and could not guarantee backward compatibility. Future sync will be performed between the projects.

How is FastFaker different?

• performance (up to 10x improvement)
• code quality (fixed over 50 gometalinter warnings)
• Templates
• error logger (stdErr) instead of silent fails
• new functions
• more documentation, new examples and tests
• usage, instead of gofakeit.Name() the calls are faker.Global.Name() or faker.NewFastFaker().Name()
• fastfaker uses the semantic version, making it compatible with go modules
• split /data and /randomizer into their own packages
• version gofakeit 3.x is fastfaker 1.x
• version gofakeit features are brought in fastfaker 2.1
• more in the changelog

Change log

All the major changes are found in the CHANGELOG.

Benchmarks

For a quick overview see BENCHMARKS.md.

Contributing

For more info see the contributing readme

TODO

See issues