services/ws/event.go

   1 // Copyright (C) The Arvados Authors. All rights reserved.
   2 //
   3 // SPDX-License-Identifier: AGPL-3.0
   4
   5 package main
   6
   7 import (
   8         "database/sql"
   9         "sync"
  10         "time"
  11
  12         "git.arvados.org/arvados.git/sdk/go/arvados"
  13         "github.com/ghodss/yaml"
  14 )
  15
  16 type eventSink interface {
  17         Channel() <-chan *event
  18         Stop()
  19 }
  20
  21 type eventSource interface {
  22         NewSink() eventSink
  23         DB() *sql.DB
  24         DBHealth() error
  25 }
  26
  27 type event struct {
  28         LogID    uint64
  29         Received time.Time
  30         Ready    time.Time
  31         Serial   uint64
  32
  33         db     *sql.DB
  34         logRow *arvados.Log
  35         err    error
  36         mtx    sync.Mutex
  37 }
  38
  39 // Detail returns the database row corresponding to the event. It can
  40 // be called safely from multiple goroutines. Only one attempt will be
  41 // made. If the database row cannot be retrieved, Detail returns nil.
  42 func (e *event) Detail() *arvados.Log {
  43         e.mtx.Lock()
  44         defer e.mtx.Unlock()
  45         if e.logRow != nil || e.err != nil {
  46                 return e.logRow
  47         }
  48         var logRow arvados.Log
  49         var propYAML []byte
  50         e.err = e.db.QueryRow(`SELECT id, uuid, object_uuid, COALESCE(object_owner_uuid,''), COALESCE(event_type,''), event_at, created_at, properties FROM logs WHERE id = $1`, e.LogID).Scan(
  51                 &logRow.ID,
  52                 &logRow.UUID,
  53                 &logRow.ObjectUUID,
  54                 &logRow.ObjectOwnerUUID,
  55                 &logRow.EventType,
  56                 &logRow.EventAt,
  57                 &logRow.CreatedAt,
  58                 &propYAML)
  59         if e.err != nil {
  60                 logger(nil).WithField("LogID", e.LogID).WithError(e.err).Error("QueryRow failed")
  61                 return nil
  62         }
  63         e.err = yaml.Unmarshal(propYAML, &logRow.Properties)
  64         if e.err != nil {
  65                 logger(nil).WithField("LogID", e.LogID).WithError(e.err).Error("yaml decode failed")
  66                 return nil
  67         }
  68         e.logRow = &logRow
  69         return e.logRow
  70 }