44 lines
1013 B
Go
44 lines
1013 B
Go
package service
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import (
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"errors"
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)
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var (
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// ErrNotImplemented is the error when a service is accessed
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// and no implementation was provided
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ErrNotImplemented = errors.New("service not implemented")
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)
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// Provider is a provider for a service
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type Provider func(ctn *Container) (interface{}, error)
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// Container is a simple service container for dependency injection
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type Container struct {
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providers map[Name]Provider
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}
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// Name is a name of a service
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type Name string
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// Provide registers a provider for the survey.Service
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func (c *Container) Provide(name Name, provider Provider) {
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c.providers[name] = provider
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}
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// Service retrieves a service implementation based on its name
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func (c *Container) Service(name Name) (interface{}, error) {
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provider, exists := c.providers[name]
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if !exists {
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return nil, ErrNotImplemented
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}
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return provider(c)
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}
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// NewContainer returns a new empty service container
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func NewContainer() *Container {
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return &Container{
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providers: make(map[Name]Provider),
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}
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}
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