Esempio n. 1
0
// Fills Vulnerability.LayersIntroducingVulnerability.
// limit -1: won't do anything
// limit 0: will just get the startID of the second page
func (pgSQL *pgSQL) loadLayerIntroducingVulnerability(vulnerability *database.Vulnerability, limit, startID int) (int, error) {
	tf := time.Now()

	if vulnerability == nil {
		return -1, nil
	}

	// A startID equals to -1 means that we reached the end already.
	if startID == -1 || limit == -1 {
		return -1, nil
	}

	// We do `defer observeQueryTime` here because we don't want to observe invalid calls.
	defer observeQueryTime("loadLayerIntroducingVulnerability", "all", tf)

	// Query with limit + 1, the last item will be used to know the next starting ID.
	rows, err := pgSQL.Query(searchNotificationLayerIntroducingVulnerability,
		vulnerability.ID, startID, limit+1)
	if err != nil {
		return 0, handleError("searchNotificationLayerIntroducingVulnerability", err)
	}
	defer rows.Close()

	var layers []database.Layer
	for rows.Next() {
		var layer database.Layer

		if err := rows.Scan(&layer.ID, &layer.Name); err != nil {
			return -1, handleError("searchNotificationLayerIntroducingVulnerability.Scan()", err)
		}

		layers = append(layers, layer)
	}
	if err = rows.Err(); err != nil {
		return -1, handleError("searchNotificationLayerIntroducingVulnerability.Rows()", err)
	}

	size := limit
	if len(layers) < limit {
		size = len(layers)
	}
	vulnerability.LayersIntroducingVulnerability = layers[:size]

	nextID := -1
	if len(layers) > limit {
		nextID = layers[limit].ID
	}

	return nextID, nil
}
Esempio n. 2
0
// Fills Vulnerability.LayersIntroducingVulnerability.
// limit -1: won't do anything
// limit 0: will just get the startID of the second page
func (pgSQL *pgSQL) loadLayerIntroducingVulnerability(vulnerability *database.Vulnerability, limit, startID int) (int, error) {
	tf := time.Now()

	if vulnerability == nil {
		return -1, nil
	}

	// A startID equals to -1 means that we reached the end already.
	if startID == -1 || limit == -1 {
		return -1, nil
	}

	// Create a transaction to disable hash joins as our experience shows that
	// PostgreSQL plans in certain cases a sequential scan and a hash on
	// Layer_diff_FeatureVersion for the condition `ldfv.layer_id >= $2 AND
	// ldfv.modification = 'add'` before realizing a hash inner join with
	// Vulnerability_Affects_FeatureVersion. By disabling explictly hash joins,
	// we force PostgreSQL to perform a bitmap index scan with
	// `ldfv.featureversion_id = fv.id` on Layer_diff_FeatureVersion, followed by
	// a bitmap heap scan on `ldfv.layer_id >= $2 AND ldfv.modification = 'add'`,
	// thus avoiding a sequential scan on the biggest database table and
	// allowing a small nested loop join instead.
	tx, err := pgSQL.Begin()
	if err != nil {
		return -1, handleError("searchNotificationLayerIntroducingVulnerability.Begin()", err)
	}
	defer tx.Commit()

	_, err = tx.Exec(disableHashJoin)
	if err != nil {
		log.Warningf("searchNotificationLayerIntroducingVulnerability: could not disable hash join: %s", err)
	}

	// We do `defer observeQueryTime` here because we don't want to observe invalid calls.
	defer observeQueryTime("loadLayerIntroducingVulnerability", "all", tf)

	// Query with limit + 1, the last item will be used to know the next starting ID.
	rows, err := tx.Query(searchNotificationLayerIntroducingVulnerability,
		vulnerability.ID, startID, limit+1)
	if err != nil {
		return 0, handleError("searchNotificationLayerIntroducingVulnerability", err)
	}
	defer rows.Close()

	var layers []database.Layer
	for rows.Next() {
		var layer database.Layer

		if err := rows.Scan(&layer.ID, &layer.Name); err != nil {
			return -1, handleError("searchNotificationLayerIntroducingVulnerability.Scan()", err)
		}

		layers = append(layers, layer)
	}
	if err = rows.Err(); err != nil {
		return -1, handleError("searchNotificationLayerIntroducingVulnerability.Rows()", err)
	}

	size := limit
	if len(layers) < limit {
		size = len(layers)
	}
	vulnerability.LayersIntroducingVulnerability = layers[:size]

	nextID := -1
	if len(layers) > limit {
		nextID = layers[limit].ID
	}

	return nextID, nil
}