first commit

service/service.go

@@ -0,0 +1,42 @@
+package service
+
+import (
+	"errors"
+)
+
+var (
+	// ErrNotImplemented is the error when a service is accessed and no implementation was provided
+	ErrNotImplemented = errors.New("service not implemented")
+)
+
+// Provider is a provider for a service
+type Provider func(ctn *Container) (interface{}, error)
+
+// Container is a simple service container for dependency injection
+type Container struct {
+	providers map[Name]Provider
+}
+
+// Name is a name of a service
+type Name string
+
+// Provide registers a provider for the survey.Service
+func (c *Container) Provide(name Name, provider Provider) {
+	c.providers[name] = provider
+}
+
+// Service retrieves a service implementation based on its name
+func (c *Container) Service(name Name) (interface{}, error) {
+	provider, exists := c.providers[name]
+	if !exists {
+		return nil, ErrNotImplemented
+	}
+	return provider(c)
+}
+
+// NewContainer returns a new empty service container
+func NewContainer() *Container {
+	return &Container{
+		providers: make(map[Name]Provider),
+	}
+}