Generate Module

Overview

Yokai provides a fxgenerate module, allowing your application to generate UUIDs.

It wraps the generate module, based on Google UUID.

Installation

The fxgenerate module is automatically loaded by Yokai's core.

When you use a Yokai application template, you have nothing to install, it's ready to use.

Usage

This module makes available the UuidGenerator in Yokai dependency injection system.

It is built on top of Google UUID, see its documentation for more details about available methods.

To access it, you just need to inject it where needed, for example:

internal/service/example.go

package service

import (
    "fmt"

    "github.com/ankorstore/yokai/generate/uuid"
)

type ExampleService struct {
    generator uuid.UuidGenerator
}

func NewExampleService(generator uuid.UuidGenerator) *ExampleService {
    return &ExampleService{
        generator: generator,
    }
}

func (s *ExampleService) DoSomething() {
    // uuid: dcb5d8b3-4517-4957-a42c-604d11758561
    fmt.Printf("uuid: %s", s.generator.Generate())
}

Testing

This module provides the possibility to make the UuidGenerator generate deterministic values (for testing purposes).

For this, you need to:

• first provide the deterministic value to be used for generation, annotated with name:"generate-test-uuid-value"
• then override the UuidGeneratorFactory with the provided TestUuidGeneratorFactory

internal/service/example_test.go

package internal_test

import (
    "testing"

    "github.com/ankorstore/yokai/fxgenerate/fxgeneratetest/uuid"
    "github.com/foo/bar/internal"
    "github.com/foo/bar/internal/service"
    "github.com/stretchr/testify/assert"
    "go.uber.org/fx"
)

func TestExampleServiceDoSomething(t *testing.T) {
    var exampleService *service.ExampleService

    internal.RunTest(
        t,
        fx.Populate(&exampleService),
        // provide and annotate the deterministic value
        fx.Provide(
            fx.Annotate(
                func() string {
                    return "some value"
                },
                fx.ResultTags(`name:"generate-test-uuid-value"`),
            ),
        ),
        // override the UuidGeneratorFactory with the TestUuidGeneratorFactory
        fx.Decorate(uuid.NewFxTestUuidGeneratorFactory),
    )

    //assertion
    assert.Equal(t, "uuid: some value", exampleService.DoSomething())
}