// Put implements the Alerts interface.
func (a *Alerts) Put(alerts ...*types.Alert) error {
dbmtx.Lock()
defer dbmtx.Unlock()
tx, err := a.db.Begin()
if err != nil {
return err
}
// The insert invariant requires that there are no two alerts with the same
// fingerprint that have overlapping activity range ([StartsAt:EndsAt]).
// Such alerts are merged into a single one with the union of both intervals
// as its new activity interval.
// The exact merge procedure is defined on the Alert structure. Here, we just
// care about finding intersecting alerts for each new inserts, deleting them
// if existant, and insert the new alert we retrieved by merging.
overlap, err := tx.Prepare(`
SELECT id, annotations, starts_at, ends_at, updated_at, timeout
FROM alerts
WHERE fingerprint == $1 AND (
(starts_at <= $2 AND ends_at >= $2) OR
(starts_at <= $3 AND ends_at >= $3)
)
`)
if err != nil {
tx.Rollback()
return err
}
defer overlap.Close()
delOverlap, err := tx.Prepare(`
DELETE FROM alerts WHERE id IN (
SELECT id FROM alerts
WHERE fingerprint == $1 AND (
(starts_at <= $2 AND ends_at >= $2) OR
(starts_at <= $3 AND ends_at >= $3)
)
)
`)
if err != nil {
tx.Rollback()
return err
}
defer delOverlap.Close()
insert, err := tx.Prepare(`
INSERT INTO alerts(fingerprint, labels, annotations, starts_at, ends_at, updated_at, timeout)
VALUES ($1, $2, $3, $4, $5, $6, $7)
`)
if err != nil {
tx.Rollback()
return err
}
defer insert.Close()
for _, alert := range alerts {
fp := alert.Fingerprint()
// Retrieve all intersecting alerts and delete them.
olaps, err := overlap.Query(int64(fp), alert.StartsAt, alert.EndsAt)
if err != nil {
tx.Rollback()
return err
}
var (
overlapIDs []int64
merges []*types.Alert
)
for olaps.Next() {
var (
id int64
na types.Alert
ann []byte
)
if err := olaps.Scan(
&id,
&ann,
&na.StartsAt,
&na.EndsAt,
&na.UpdatedAt,
&na.Timeout,
); err != nil {
tx.Rollback()
return err
}
if err := json.Unmarshal(ann, &na.Annotations); err != nil {
tx.Rollback()
return err
}
na.Labels = alert.Labels
merges = append(merges, &na)
overlapIDs = append(overlapIDs, id)
}
if err := olaps.Err(); err != nil {
tx.Rollback()
return err
}
// Merge them.
for _, ma := range merges {
alert = alert.Merge(ma)
}
// Delete the old ones.
if _, err := delOverlap.Exec(int64(fp), alert.StartsAt, alert.EndsAt); err != nil {
tx.Rollback()
return err
}
// Insert the final alert.
labels, err := json.Marshal(alert.Labels)
if err != nil {
tx.Rollback()
return err
}
annotations, err := json.Marshal(alert.Annotations)
if err != nil {
tx.Rollback()
return err
}
_, err = insert.Exec(
int64(fp),
labels,
annotations,
alert.StartsAt,
alert.EndsAt,
alert.UpdatedAt,
alert.Timeout,
)
if err != nil {
tx.Rollback()
return err
}
a.mtx.RLock()
for _, ch := range a.listeners {
ch <- alert
}
a.mtx.RUnlock()
}
tx.Commit()
return nil
}
