Changed caching to only load the fields required for generating the campaign emails.

models/campaign.go

@@ -362,6 +362,38 @@ func GetCampaignSummary(id int64, uid int64) (CampaignSummary, error) {
 	return cs, nil
 }
 
+// GetCampaignMailContext returns a campaign object with just the relevant
+// data needed to generate and send emails. This includes the top-level
+// metadata, the template, and the sending profile.
+//
+// This should only ever be used if you specifically want this lightweight
+// context, since it returns a non-standard campaign object.
+// ref: #1726
+func GetCampaignMailContext(id int64, uid int64) (Campaign, error) {
+	c := Campaign{}
+	err := db.Where("id = ?", id).Where("user_id = ?", uid).Find(&c).Error
+	if err != nil {
+		return c, err
+	}
+	err = db.Table("smtp").Where("id=?", c.SMTPId).Find(&c.SMTP).Error
+	if err != nil {
+		return c, err
+	}
+	err = db.Where("smtp_id=?", c.SMTP.Id).Find(&c.SMTP.Headers).Error
+	if err != nil && err != gorm.ErrRecordNotFound {
+		return c, err
+	}
+	err = db.Table("templates").Where("id=?", c.TemplateId).Find(&c.Template).Error
+	if err != nil {
+		return c, err
+	}
+	err = db.Where("template_id=?", c.Template.Id).Find(&c.Template.Attachments).Error
+	if err != nil && err != gorm.ErrRecordNotFound {
+		return c, err
+	}
+	return c, nil
+}
+
 // GetCampaign returns the campaign, if it exists, specified by the given id and user_id.
 func GetCampaign(id int64, uid int64) (Campaign, error) {
 	c := Campaign{}

models/maillog.go

@@ -132,7 +132,7 @@ func (m *MailLog) Success() error {
 func (m *MailLog) GetDialer() (mailer.Dialer, error) {
 	c := m.cachedCampaign
 	if c == nil {
-		campaign, err := GetCampaign(m.CampaignId, m.UserId)
+		campaign, err := GetCampaignMailContext(m.CampaignId, m.UserId)
 		if err != nil {
 			return nil, err
 		}
@@ -162,7 +162,7 @@ func (m *MailLog) Generate(msg *gomail.Message) error {
 	}
 	c := m.cachedCampaign
 	if c == nil {
-		campaign, err := GetCampaign(m.CampaignId, m.UserId)
+		campaign, err := GetCampaignMailContext(m.CampaignId, m.UserId)
 		if err != nil {
 			return err
 		}

worker/worker.go

@@ -69,7 +69,7 @@ func (w *DefaultWorker) processCampaigns(t time.Time) error {
 		// generate the message (ref #1726)
 		c, ok := campaignCache[m.CampaignId]
 		if !ok {
-			c, err = models.GetCampaign(m.CampaignId, m.UserId)
+			c, err = models.GetCampaignMailContext(m.CampaignId, m.UserId)
 			if err != nil {
 				return err
 			}