使用Uber FX提供一个接口

huangapple
go评论140阅读模式
英文:

Using uber fx to provide an interface

问题

我正在尝试使用uber fx为Go微服务项目进行依赖注入。

由于所有的微服务都需要构建一个基础服务器，并设置各种配置选项（如常见的中间件、缓冲区大小等）（我正在使用fiber）。但是这些不同的微服务也有各自特定的配置选项，比如数据库连接字符串、JWT密钥等。

我创建了一个接口，在共享函数中使用该接口创建通用的基础应用程序，并带有共同的选项，但是任何需要依赖配置结构的函数都会失败，因为它们期望特定版本的微服务配置。

> failed to build *fiber.App: missing dependencies for function "some-path/http".CreateServer (some-path/http/http.go:65): missing type: *http.Config
exit status 1

最小示例：

http/http.go

  1. package http
  3. import (
  4. 	"time"
  6. 	"github.com/gofiber/fiber/v2"
  7. )
  10. type BaseConfig interface {
  11. 	GetPort() string
  12. 	GetTimeout() int
  13. }
  15. type Config struct {
  16. 	Port           string `env:"LISTEN_ADDR" envDefault:":3000"`
  17. 	Timeout        uint64 `env:"TIMEOUT" envDefault:"10"`
  18. }
  20. func (c *Config) GetPort() string {
  21. 	return c.Port
  22. }
  24. func (c *Config) GetTimeout() int {
  25. 	return int(c.Timeout)
  26. }
  28. func CreateServer(config *Config) *fiber.App {
  29. 	fiberConfig := fiber.Config{
  30. 		ReadTimeout:    time.Second * time.Duration(config.GetTimeout()),
  31. 		WriteTimeout:   time.Second * time.Duration(config.GetTimeout()),
  32. 	}
  34. 	app := fiber.New(fiberConfig)
  36. 	// do setup and other stuff
  38. 	return app
  39. }

some-service/config/config.go

  1. package config
  3. import (
  4. 	"github.com/caarlos0/env/v6"
  5. 	"github.com/rs/zerolog/log"
  6. )
  8. type Config struct {
  9. 	Port                string        `env:"LISTEN_ADDR" envDefault:":3000"`
  10. 	Timeout             uint64        `env:"TIMEOUT" envDefault:"10"`
  11.     // some service specific stuff as well
  12. }
  14. func Parse() (*Config, error) {
  15. 	cfg := Config{}
  17. 	if err := env.Parse(&cfg); err != nil {
  18. 		return nil, err
  19. 	}
  21. 	return &cfg, nil
  22. }
  24. func (c *Config) GetPort() string {
  25. 	return c.Port
  26. }
  28. func (c *Config) GetTimeout() int {
  29. 	return int(c.Timeout)
  30. }

some-service/main.go

  1. package main
  3. import (
  4. 	"context"
  5. 	"time"
  7. 	"some-path/http"
  8. 	"some-path/config"
  9.     "some-path/controllers"
  10. 	"github.com/gofiber/fiber/v2"
  11. 	"go.uber.org/fx"
  12. )
  14. func main() {
  16. 	opts := []fx.Option{}
  17. 	opts = append(opts, provideOptions()...)
  18. 	opts = append(opts, fx.Invoke(run))
  20. 	app := fx.New(opts...)
  22. 	app.Run()
  23. }
  25. func provideOptions() []fx.Option {
  26. 	return []fx.Option{
  27. 		fx.Invoke(utils.ConfigureLogger),
  28. 		fx.Provide(config.Parse),
  29.         fx.Invoke(controllers.SomeController),
  30. 	}
  31. }
  33. func run(app *fiber.App, config *config.Config, lc fx.Lifecycle) {
  34. 	lc.Append(fx.Hook{
  35. 		OnStart: func(ctx context.Context) error {
  36. 			errChan := make(chan error)
  38. 			go func() {
  39. 				errChan <- app.Listen(config.Port)
  40. 			}()
  42. 			select {
  43. 			case err := <-errChan:
  44. 				return err
  45. 			case <-time.After(100 * time.Millisecond):
  46. 				return nil
  47. 			}
  48. 		},
  49. 		OnStop: func(ctx context.Context) error {
  50. 			return app.Shutdown()
  51. 		},
  52. 	})
  53. }

some-path/controllers/some-controller.go

  1. package controllers
  3. import "some-path/config"
  5. func SomeController (config *config.Config) {
  6.     // do stuff
  7. }
英文:

I am attempting to use uber fx to do dependency injection for a go microservice project.

Since all the microservices will need to construct a base server, and set up a variety of config options (common middleware, buffer sizes etc) (I am using fiber). But these different microservices also have config options unique to the microservice. Maybe a database connection string, jwt keys etc.

I created an interface to use in the shared function that creates the common base app, with the common options, but any function needing a dependency of the config struct fails with expecting the specific version of config for that microservice.

> failed to build *fiber.App: missing dependencies for function "some-path/http".CreateServer (some-path/http/http.go:65): missing type: *http.Config
exit status 1

Minimal example:

http/http.go

  1. package http
  3. import (
  4. 	&quot;time&quot;
  6. 	&quot;github.com/gofiber/fiber/v2&quot;
  7. )
  10. type BaseConfig interface {
  11. 	GetPort() string
  12. 	GetTimeout() int
  13. }
  15. type Config struct {
  16. 	Port           string `env:&quot;LISTEN_ADDR&quot; envDefault:&quot;:3000&quot;`
  17. 	Timeout        uint64 `env:&quot;TIMEOUT&quot; envDefault:&quot;10&quot;`
  18. }
  20. func (c *Config) GetPort() string {
  21. 	return c.Port
  22. }
  24. func (c *Config) GetTimeout() int {
  25. 	return int(c.Timeout)
  26. }
  28. func CreateServer(config *Config) *fiber.App {
  29. 	fiberConfig := fiber.Config{
  30. 		ReadTimeout:    time.Second * time.Duration(config.GetTimeout()),
  31. 		WriteTimeout:   time.Second * time.Duration(config.GetTimeout()),
  32. 	}
  34. 	app := fiber.New(fiberConfig)
  36. 	// do setup and other stuff
  38. 	return app
  39. }

some-service/config/config.go

  1. package config
  3. import (
  4. 	&quot;github.com/caarlos0/env/v6&quot;
  5. 	&quot;github.com/rs/zerolog/log&quot;
  6. )
  8. type Config struct {
  9. 	Port                string        `env:&quot;LISTEN_ADDR&quot; envDefault:&quot;:3000&quot;`
  10. 	Timeout             uint64        `env:&quot;TIMEOUT&quot; envDefault:&quot;10&quot;`
  11.     // some service specific stuff as well
  12. }
  14. func Parse() (*Config, error) {
  15. 	cfg := Config{}
  17. 	if err := env.Parse(&amp;cfg); err != nil {
  18. 		return nil, err
  19. 	}
  21. 	return &amp;cfg, nil
  22. }
  24. func (c *Config) GetPort() string {
  25. 	return c.Port
  26. }
  28. func (c *Config) GetTimeout() int {
  29. 	return int(c.Timeout)
  30. }

some-service/main.go

  1. package main
  3. import (
  4. 	&quot;context&quot;
  5. 	&quot;time&quot;
  7. 	&quot;some-path/http&quot;
  8. 	&quot;some-path/config&quot;
  9.     &quot;some-path/controllers&quot;
  10. 	&quot;github.com/gofiber/fiber/v2&quot;
  11. 	&quot;go.uber.org/fx&quot;
  12. )
  14. func main() {
  16. 	opts := []fx.Option{}
  17. 	opts = append(opts, provideOptions()...)
  18. 	opts = append(opts, fx.Invoke(run))
  20. 	app := fx.New(opts...)
  22. 	app.Run()
  23. }
  25. func provideOptions() []fx.Option {
  26. 	return []fx.Option{
  27. 		fx.Invoke(utils.ConfigureLogger),
  28. 		fx.Provide(config.Parse),
  29.         fx.Invoke(controllers.SomeController),
  30. 	}
  31. }
  33. func run(app *fiber.App, config *config.Config, lc fx.Lifecycle) {
  34. 	lc.Append(fx.Hook{
  35. 		OnStart: func(ctx context.Context) error {
  36. 			errChan := make(chan error)
  38. 			go func() {
  39. 				errChan &lt;- app.Listen(config.Port)
  40. 			}()
  42. 			select {
  43. 			case err := &lt;-errChan:
  44. 				return err
  45. 			case &lt;-time.After(100 * time.Millisecond):
  46. 				return nil
  47. 			}
  48. 		},
  49. 		OnStop: func(ctx context.Context) error {
  50. 			return app.Shutdown()
  51. 		},
  52. 	})
  53. }

some-path/controllers/some-controller.go

  1. package controllers
  3. import &quot;some-path/config&quot;
  5. func SomeController (config *config.Config) {
  6.     // do stuff
  7. }
  9. </details>
  12. # 答案1
  13. **得分**: 0
  15. 你缺少`*http.Config`对象，请创建一个返回该对象的函数，例如`NewConfig()`。
  17. ```go
  18. package http
  20. import (
  21. 	"time"
  23. 	"github.com/caarlos0/env/v6"
  24. 	"github.com/gofiber/fiber/v2"
  25. )
  27. type BaseConfig interface {
  28. 	GetPort() string
  29. 	GetTimeout() int
  30. }
  32. type Config struct {
  33. 	Port    string `env:"LISTEN_ADDR" envDefault:":3000"`
  34. 	Timeout uint64 `env:"TIMEOUT" envDefault:"10"`
  35. }
  37. func NewConfig() (*Config, error) {
  38. 	cfg := Config{}
  40. 	if err := env.Parse(&cfg); err != nil {
  41. 		return nil, err
  42. 	}
  44. 	return &cfg, nil
  45. }
  47. func (c *Config) GetPort() string {
  48. 	return c.Port
  49. }
  51. func (c *Config) GetTimeout() int {
  52. 	return int(c.Timeout)
  53. }
  55. func CreateServer(config *Config) *fiber.App {
  56. 	fiberConfig := fiber.Config{
  57. 		ReadTimeout:  time.Second * time.Duration(config.GetTimeout()),
  58. 		WriteTimeout: time.Second * time.Duration(config.GetTimeout()),
  59. 	}
  61. 	app := fiber.New(fiberConfig)
  63. 	// 进行设置和其他操作
  65. 	return app
  66. }

然后修改你的provideOptions()函数，可能像这样：

  1. func provideOptions() []fx.Option {
  2. 	return []fx.Option{
  3. 		fx.Invoke(utils.ConfigureLogger),
  4. 		fx.Provide(config.Parse, http.NewConfig),
  5. 		fx.Invoke(controllers.SomeController),
  6. 		fx.Provide(http.CreateServer),
  7. 	}
  8. }
英文:

You're missing *http.Config object, create a function that return that object, e.g. NewConfig()

  1. package http
  3. import (
  4. 	&quot;time&quot;
  6. 	&quot;github.com/caarlos0/env/v6&quot;
  7. 	&quot;github.com/gofiber/fiber/v2&quot;
  8. )
  10. type BaseConfig interface {
  11. 	GetPort() string
  12. 	GetTimeout() int
  13. }
  15. type Config struct {
  16. 	Port    string `env:&quot;LISTEN_ADDR&quot; envDefault:&quot;:3000&quot;`
  17. 	Timeout uint64 `env:&quot;TIMEOUT&quot; envDefault:&quot;10&quot;`
  18. }
  20. func NewConfig() (*Config, error) {
  21. 	cfg := Config{}
  23. 	if err := env.Parse(&amp;cfg); err != nil {
  24. 		return nil, err
  25. 	}
  27. 	return &amp;cfg, nil
  28. }
  30. func (c *Config) GetPort() string {
  31. 	return c.Port
  32. }
  34. func (c *Config) GetTimeout() int {
  35. 	return int(c.Timeout)
  36. }
  38. func CreateServer(config *Config) *fiber.App {
  39. 	fiberConfig := fiber.Config{
  40. 		ReadTimeout:  time.Second * time.Duration(config.GetTimeout()),
  41. 		WriteTimeout: time.Second * time.Duration(config.GetTimeout()),
  42. 	}
  44. 	app := fiber.New(fiberConfig)
  46. 	// do setup and other stuff
  48. 	return app
  49. }

then change your provideOptions(), maybe like this:

  1. func provideOptions() []fx.Option {
  2. 	return []fx.Option{
  3. 		fx.Invoke(utils.ConfigureLogger),
  4. 		fx.Provide(config.Parse, http.NewConfig),
  5. 		fx.Invoke(controllers.SomeController),
  6. 		fx.Provide(http.CreateServer),
  7. 	}
  8. }

huangapple
  • 本文由 发表于 2022年3月1日 20:44:48
  • 转载请务必保留本文链接：https://go.coder-hub.com/71308704.html
  • dependency-injection
  • go
  • go-uber-fx
匿名

发表评论

匿名网友

:?: :razz: :sad: :evil: :!: :smile: :oops: :grin: :eek: :shock: :???: :cool: :lol: :mad: :twisted: :roll: :wink: :idea: :arrow: :neutral: :cry: :mrgreen:

确定