How to inject services recursively into struct fields

This guide describes a feature of the github.com/go-nacelle/service package. See related documentation.

It should be noted that injection does not work recursively. The procedure does not look into the values of non-anonymous fields. If this behavior is needed, it can be performed during a post-injection hook. The following example demonstrates this behavior.

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type RecursiveInjectionConsumer struct {
	Services *service.ServiceContainer `service:"services"`
	FieldA   *A
	FieldB   *B
	FieldC   *C
}

func (c *RecursiveInjectionConsumer) PostInject() error {
	fields := []interface{}{
		c.FieldA,
		c.FieldB,
		c.FieldC,
	}

	for _, field := range fields {
		if err := c.Services.Inject(field); err != nil {
			return err
		}
	}

	return nil
}