Define a metadata subrouter

Define a metadata subrouter and move the token endpoint there. We may
end up needing multiple endpoints for various purposes in the future.

Signed-off-by: Gabriel Adrian Samfira <gsamfira@cloudbasesolutions.com>

database/sql/instances.go

@@ -47,6 +47,7 @@ func (s *sqlDatabase) CreateInstance(ctx context.Context, poolID string, param p
 		OSType:                  param.OSType,
 		OSArch:                  param.OSArch,
 		CallbackURL:             param.CallbackURL,
+		MetadataURL:             param.MetadataURL,
 		GithubRegistrationToken: ghToken,
 	}
 	q := s.conn.Create(&newInstance)

database/sql/models.go

@@ -138,6 +138,7 @@ type Instance struct {
 	Status                  common.InstanceStatus
 	RunnerStatus            common.RunnerStatus
 	CallbackURL             string
+	MetadataURL             string
 	ProviderFault           []byte `gorm:"type:longblob"`
 	CreateAttempt           int
 	GithubRegistrationToken []byte `gorm:"type:longblob"`

database/sql/util.go

@@ -41,6 +41,7 @@ func (s *sqlDatabase) sqlToParamsInstance(instance Instance) params.Instance {
 		RunnerStatus:            instance.RunnerStatus,
 		PoolID:                  instance.PoolID.String(),
 		CallbackURL:             instance.CallbackURL,
+		MetadataURL:             instance.MetadataURL,
 		StatusMessages:          []params.StatusMessage{},
 		CreateAttempt:           instance.CreateAttempt,
 		UpdatedAt:               instance.UpdatedAt,