func (c *GrpcChecker) Run() []*plugins.Message {
	c.analyzeOpenAPIDocument()
	return c.messages
}
Runs the checker. It is a top-down approach.
package generator
import (
	openapiv3 "github.com/google/gnostic/openapiv3"
	plugins "github.com/google/gnostic/plugins"
)
type GrpcChecker struct {
	document *openapiv3.Document
	messages []*plugins.Message
}
func NewGrpcChecker(document *openapiv3.Document) *GrpcChecker {
	return &GrpcChecker{document: document, messages: make([]*plugins.Message, 0)}
}