Add support for multiple subscribers in a single transactional message call.

This patch adds new array fields on `POST /tx`: `subscriber_emails[]`, `subscriber_ids[]`.
Either of these array fields can be sent with multiple subscribers.

The individual non-array fields `subscriber_id` and `subscriber_email` are deprecated.

Closes #994.

cmd/tx.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"net/http"
 	"net/textproto"
+	"strings"
 
 	"github.com/knadh/listmonk/internal/manager"
 	"github.com/knadh/listmonk/models"
@@ -35,58 +36,110 @@ func handleSendTxMessage(c echo.Context) error {
 			app.i18n.Ts("globals.messages.notFound", "name", fmt.Sprintf("template %d", m.TemplateID)))
 	}
 
-	// Get the subscriber.
-	sub, err := app.core.GetSubscriber(m.SubscriberID, "", m.SubscriberEmail)
-	if err != nil {
-		return err
+	var (
+		num      = len(m.SubscriberEmails)
+		isEmails = true
+	)
+	if len(m.SubscriberIDs) > 0 {
+		num = len(m.SubscriberIDs)
+		isEmails = false
 	}
 
-	// Render the message.
-	if err := m.Render(sub, tpl); err != nil {
-		return echo.NewHTTPError(http.StatusBadRequest,
-			app.i18n.Ts("globals.messages.errorFetching", "name"))
-	}
+	notFound := []string{}
+	for n := 0; n < num; n++ {
+		var (
+			subID    int
+			subEmail string
+		)
 
-	// Prepare the final message.
-	msg := manager.Message{}
-	msg.Subscriber = sub
-	msg.To = []string{sub.Email}
-	msg.From = m.FromEmail
-	msg.Subject = m.Subject
-	msg.ContentType = m.ContentType
-	msg.Messenger = m.Messenger
-	msg.Body = m.Body
+		if !isEmails {
+			subID = m.SubscriberIDs[n]
+		} else {
+			subEmail = m.SubscriberEmails[n]
+		}
 
-	// Optional headers.
-	if len(m.Headers) != 0 {
-		msg.Headers = make(textproto.MIMEHeader, len(m.Headers))
-		for _, set := range m.Headers {
-			for hdr, val := range set {
-				msg.Headers.Add(hdr, val)
+		// Get the subscriber.
+		sub, err := app.core.GetSubscriber(subID, "", subEmail)
+		if err != nil {
+			// If the subscriber is not found, log that error and move on without halting on the list.
+			if er, ok := err.(*echo.HTTPError); ok && er.Code == http.StatusBadRequest {
+				notFound = append(notFound, fmt.Sprintf("%v", er.Message))
+				continue
 			}
+
+			return err
+		}
+
+		// Render the message.
+		if err := m.Render(sub, tpl); err != nil {
+			return echo.NewHTTPError(http.StatusBadRequest,
+				app.i18n.Ts("globals.messages.errorFetching", "name"))
+		}
+
+		// Prepare the final message.
+		msg := manager.Message{}
+		msg.Subscriber = sub
+		msg.To = []string{sub.Email}
+		msg.From = m.FromEmail
+		msg.Subject = m.Subject
+		msg.ContentType = m.ContentType
+		msg.Messenger = m.Messenger
+		msg.Body = m.Body
+
+		// Optional headers.
+		if len(m.Headers) != 0 {
+			msg.Headers = make(textproto.MIMEHeader, len(m.Headers))
+			for _, set := range m.Headers {
+				for hdr, val := range set {
+					msg.Headers.Add(hdr, val)
+				}
+			}
+		}
+
+		if err := app.manager.PushMessage(msg); err != nil {
+			app.log.Printf("error sending message (%s): %v", msg.Subject, err)
+			return err
 		}
 	}
 
-	if err := app.manager.PushMessage(msg); err != nil {
-		app.log.Printf("error sending message (%s): %v", msg.Subject, err)
-		return err
+	if len(notFound) > 0 {
+		return echo.NewHTTPError(http.StatusBadRequest, strings.Join(notFound, "; "))
 	}
 
 	return c.JSON(http.StatusOK, okResp{true})
 }
 
 func validateTxMessage(m models.TxMessage, app *App) (models.TxMessage, error) {
-	if m.SubscriberEmail == "" && m.SubscriberID == 0 {
+	if len(m.SubscriberEmails) > 0 && m.SubscriberEmail != "" {
 		return m, echo.NewHTTPError(http.StatusBadRequest,
-			app.i18n.Ts("globals.messages.missingFields", "name", "subscriber_email or subscriber_id"))
+			app.i18n.Ts("globals.messages.invalidFields", "name", "do not send `subscriber_email`"))
+	}
+	if len(m.SubscriberIDs) > 0 && m.SubscriberID != 0 {
+		return m, echo.NewHTTPError(http.StatusBadRequest,
+			app.i18n.Ts("globals.messages.invalidFields", "name", "do not send `subscriber_id`"))
 	}
 
 	if m.SubscriberEmail != "" {
-		em, err := app.importer.SanitizeEmail(m.SubscriberEmail)
-		if err != nil {
-			return m, echo.NewHTTPError(http.StatusBadRequest, err.Error())
+		m.SubscriberEmails = append(m.SubscriberEmails, m.SubscriberEmail)
+	}
+
+	if m.SubscriberID != 0 {
+		m.SubscriberIDs = append(m.SubscriberIDs, m.SubscriberID)
+	}
+
+	if (len(m.SubscriberEmails) == 0 && len(m.SubscriberIDs) == 0) || (len(m.SubscriberEmails) > 0 && len(m.SubscriberIDs) > 0) {
+		return m, echo.NewHTTPError(http.StatusBadRequest,
+			app.i18n.Ts("globals.messages.invalidFields", "name", "send subscriber_emails OR subscriber_ids"))
+	}
+
+	for n, email := range m.SubscriberEmails {
+		if m.SubscriberEmail != "" {
+			em, err := app.importer.SanitizeEmail(email)
+			if err != nil {
+				return m, echo.NewHTTPError(http.StatusBadRequest, err.Error())
+			}
+			m.SubscriberEmails[n] = em
 		}
-		m.SubscriberEmail = em
 	}
 
 	if m.FromEmail == "" {

i18n/ca.json

@@ -170,6 +170,7 @@
     "globals.messages.errorUpdating": "Error en actualitzar {name}: {error}",
     "globals.messages.internalError": "Error del servidor intern",
     "globals.messages.invalidData": "Dades no vàlides",
+    "globals.messages.invalidFields": "Invalid fields: {name}",
     "globals.messages.invalidID": "ID(s) no vàlid",
     "globals.messages.invalidUUID": "UUID(s) no vàlid",
     "globals.messages.missingFields": "Falten camps: {name}",

i18n/cs-cz.json

@@ -170,6 +170,7 @@
     "globals.messages.errorUpdating": "Chyba při aktualizaci {name}: {error}",
     "globals.messages.internalError": "Interní chyba serveru",
     "globals.messages.invalidData": "Neplatná data",
+    "globals.messages.invalidFields": "Invalid fields: {name}",
     "globals.messages.invalidID": "Neplatné ID",
     "globals.messages.invalidUUID": "Neplatné UUID",
     "globals.messages.missingFields": "Chybějící pole: {name}",

i18n/de.json

@@ -170,6 +170,7 @@
     "globals.messages.errorUpdating": "Fehler beim Aktualisieren von {name}: {error}",
     "globals.messages.internalError": "Interner Serverfehler",
     "globals.messages.invalidData": "Ungültige Daten",
+    "globals.messages.invalidFields": "Invalid fields: {name}",
     "globals.messages.invalidID": "Ungültige ID",
     "globals.messages.invalidUUID": "Ungültige UUID",
     "globals.messages.missingFields": "Fehlende Felder: {name}",

i18n/en.json

@@ -170,6 +170,7 @@
     "globals.messages.errorUpdating": "Error updating {name}: {error}",
     "globals.messages.internalError": "Internal server error",
     "globals.messages.invalidData": "Invalid data",
+    "globals.messages.invalidFields": "Invalid fields: {name}",
     "globals.messages.invalidID": "Invalid ID(s)",
     "globals.messages.invalidUUID": "Invalid UUID(s)",
     "globals.messages.missingFields": "Missing field(s): {name}",

i18n/es.json

@@ -171,6 +171,7 @@
     "globals.messages.errorUpdating": "Error actualizando {name}: {error}",
     "globals.messages.internalError": "Error interno del servidor.",
     "globals.messages.invalidData": "Datos invalidos",
+    "globals.messages.invalidFields": "Invalid fields: {name}",
     "globals.messages.invalidID": "ID inválido",
     "globals.messages.invalidUUID": "UUID inválido",
     "globals.messages.missingFields": "Cambpo(s) faltantes: {name}",

i18n/fi.json

@@ -171,6 +171,7 @@
     "globals.messages.errorUpdating": "Error updating {name}: {error}",
     "globals.messages.internalError": "Internal server error",
     "globals.messages.invalidData": "Invalid data",
+    "globals.messages.invalidFields": "Invalid fields: {name}",
     "globals.messages.invalidID": "Invalid ID(s)",
     "globals.messages.invalidUUID": "Invalid UUID(s)",
     "globals.messages.missingFields": "Missing field(s): {name}",

i18n/fr.json

@@ -171,6 +171,7 @@
     "globals.messages.errorUpdating": "Erreur lors de la mise à jour de {name} : {error}",
     "globals.messages.internalError": "Erreur interne du serveur",
     "globals.messages.invalidData": "Données invalides",
+    "globals.messages.invalidFields": "Invalid fields: {name}",
     "globals.messages.invalidID": "ID invalide",
     "globals.messages.invalidUUID": "UUID invalide",
     "globals.messages.missingFields": "Champ(s) manquant(s) : {name}",

i18n/hu.json

@@ -171,6 +171,7 @@
     "globals.messages.errorUpdating": "Hiba a frissítés során {name}: {error}",
     "globals.messages.internalError": "Belső Szerverhiba",
     "globals.messages.invalidData": "Érvénytelen adat",
+    "globals.messages.invalidFields": "Invalid fields: {name}",
     "globals.messages.invalidID": "Érvénytelen ID(s)",
     "globals.messages.invalidUUID": "Érvénytelen UUID(s)",
     "globals.messages.missingFields": "Hiányzó mező(k): {name}",

i18n/it.json

@@ -171,6 +171,7 @@
     "globals.messages.errorUpdating": "Errore durante l'aggiornamento di {name}: {error}",
     "globals.messages.internalError": "Errore interno nel server",
     "globals.messages.invalidData": "Dati non validi",
+    "globals.messages.invalidFields": "Invalid fields: {name}",
     "globals.messages.invalidID": "ID non valido",
     "globals.messages.invalidUUID": "UUID non valido",
     "globals.messages.missingFields": "Valore/i mancante/i: {name}",

i18n/jp.json

@@ -171,6 +171,7 @@
     "globals.messages.errorUpdating": "{name}更新エラー: {error}",
     "globals.messages.internalError": "内部サーバーエラー",
     "globals.messages.invalidData": "無効なデータ",
+    "globals.messages.invalidFields": "Invalid fields: {name}",
     "globals.messages.invalidID": "無効なID",
     "globals.messages.invalidUUID": "無効なUUID",
     "globals.messages.missingFields": "フィールドがありません: {name}",

i18n/ml.json

@@ -170,6 +170,7 @@
     "globals.messages.errorUpdating": "{name} പുതുക്കുന്നതിൽ പിശകുണ്ടായി: {error}",
     "globals.messages.internalError": "സേർവറിനു തകരാറുപറ്റി",
     "globals.messages.invalidData": "അസാധുവായ വിവരം",
+    "globals.messages.invalidFields": "Invalid fields: {name}",
     "globals.messages.invalidID": "ഐഡി അസാധുവാണ്",
     "globals.messages.invalidUUID": "യുയുഐഡി അസാധുവാണ്",
     "globals.messages.missingFields": "വിട്ടുപോയ ഫീൽഡ്(കൾ): {name}",

i18n/nl.json

@@ -171,6 +171,7 @@
     "globals.messages.errorUpdating": "Fout bij updaten {name}: {error}",
     "globals.messages.internalError": "Interne serverfout",
     "globals.messages.invalidData": "Ongeldige data",
+    "globals.messages.invalidFields": "Invalid fields: {name}",
     "globals.messages.invalidID": "Ongeldige ID(s)",
     "globals.messages.invalidUUID": "Ongeldige UUID(s)",
     "globals.messages.missingFields": "Ontbrekend(e) veld(en): {name}",

i18n/pl.json

@@ -171,6 +171,7 @@
     "globals.messages.errorUpdating": "Błąd podczas aktualizacji {name}: {error}",
     "globals.messages.internalError": "Internal server error",
     "globals.messages.invalidData": "Invalid data",
+    "globals.messages.invalidFields": "Invalid fields: {name}",
     "globals.messages.invalidID": "Nieprawidłowy iD",
     "globals.messages.invalidUUID": "Nieprawidłowy UUID",
     "globals.messages.missingFields": "Missing field(s): {name}",

i18n/pt-BR.json

@@ -170,6 +170,7 @@
     "globals.messages.errorUpdating": "Erro ao atualizar {name}: {error}",
     "globals.messages.internalError": "Erro no servidor",
     "globals.messages.invalidData": "Dados inválidos",
+    "globals.messages.invalidFields": "Invalid fields: {name}",
     "globals.messages.invalidID": "ID inválido",
     "globals.messages.invalidUUID": "UUID inválido",
     "globals.messages.missingFields": "Campos ausente(s): {name}",

i18n/pt.json

@@ -170,6 +170,7 @@
     "globals.messages.errorUpdating": "Erro ao atualizar {name}: {error}",
     "globals.messages.internalError": "Erro interno no servidor",
     "globals.messages.invalidData": "Dados inválidos",
+    "globals.messages.invalidFields": "Invalid fields: {name}",
     "globals.messages.invalidID": "ID inválido",
     "globals.messages.invalidUUID": "UUID inválido",
     "globals.messages.missingFields": "Campo(s) em falta: {name}",

i18n/ro.json

@@ -171,6 +171,7 @@
     "globals.messages.errorUpdating": "Eroare actualizare {nume}: {eroare}",
     "globals.messages.internalError": "Eroare server intern",
     "globals.messages.invalidData": "Date invalide",
+    "globals.messages.invalidFields": "Invalid fields: {name}",
     "globals.messages.invalidID": "ID(uri) invalide",
     "globals.messages.invalidUUID": "UUID(uri) invalide",
     "globals.messages.missingFields": "Camuri lipsă: {nume}",

i18n/ru.json

@@ -170,6 +170,7 @@
     "globals.messages.errorUpdating": "Ошибка обновления {name}: {error}",
     "globals.messages.internalError": "Внутренняя ошибка сервера",
     "globals.messages.invalidData": "Неверные данные",
+    "globals.messages.invalidFields": "Invalid fields: {name}",
     "globals.messages.invalidID": "Неверный ID",
     "globals.messages.invalidUUID": "Неверный UUID",
     "globals.messages.missingFields": "Отсутствующее поле (поля): {name}",

i18n/tr.json

@@ -147,6 +147,7 @@
     "globals.days.4": "Per",
     "globals.days.5": "Cum",
     "globals.days.6": "Cmt",
+    "globals.days.7": "Sat",
     "globals.fields.createdAt": "Yaratılma",
     "globals.fields.description": "Açıklama",
     "globals.fields.id": "ID",
@@ -170,6 +171,7 @@
     "globals.messages.errorUpdating": "Hata güncellerken {name}: {error}",
     "globals.messages.internalError": "Sunucu hatası",
     "globals.messages.invalidData": "Geçersiz veri",
+    "globals.messages.invalidFields": "Invalid fields: {name}",
     "globals.messages.invalidID": "Yanlış ID",
     "globals.messages.invalidUUID": "Yanlış UUID",
     "globals.messages.missingFields": "Eksik alan(lar): {name}",
@@ -177,6 +179,9 @@
     "globals.messages.passwordChange": "Değiştirmek için değer gir",
     "globals.messages.updated": "\"{name}\" güncellendi",
     "globals.months.1": "Oca",
+    "globals.months.10": "Eki",
+    "globals.months.11": "Kas",
+    "globals.months.12": "Ara",
     "globals.months.2": "Şub",
     "globals.months.3": "Mar",
     "globals.months.4": "Nis",
@@ -185,9 +190,6 @@
     "globals.months.7": "Tem",
     "globals.months.8": "Ağu",
     "globals.months.9": "Eyl",
-    "globals.months.10": "Eki",
-    "globals.months.11": "Kas",
-    "globals.months.12": "Ara",
     "globals.states.off": "Off",
     "globals.terms.all": "All",
     "globals.terms.analytics": "Analitik",

i18n/vi.json

@@ -171,6 +171,7 @@
     "globals.messages.errorUpdating": "Lỗi khi cập nhật {name}: {error}",
     "globals.messages.internalError": "Lỗi máy chủ nội bộ",
     "globals.messages.invalidData": "Dữ liệu không hợp lệ",
+    "globals.messages.invalidFields": "Invalid fields: {name}",
     "globals.messages.invalidID": "ID(s) không hợp lệ",
     "globals.messages.invalidUUID": " UUID(s) không hợp lệ",
     "globals.messages.missingFields": "Lỗi field(s): {name}",

i18n/zh-CN.json

@@ -170,6 +170,7 @@
     "globals.messages.errorUpdating": "更新 {name} 时出错：{error}",
     "globals.messages.internalError": "内部服务器错误",
     "globals.messages.invalidData": "无效数据",
+    "globals.messages.invalidFields": "Invalid fields: {name}",
     "globals.messages.invalidID": "ID 无效",
     "globals.messages.invalidUUID": "无效的 UUID",
     "globals.messages.missingFields": "缺少字段：{name}",

i18n/zh-TW.json

@@ -171,6 +171,7 @@
     "globals.messages.errorUpdating": "更新{name} 時出錯：{error}",
     "globals.messages.internalError": "內部服務器錯誤",
     "globals.messages.invalidData": "無效數據",
+    "globals.messages.invalidFields": "Invalid fields: {name}",
     "globals.messages.invalidID": "ID 無效",
     "globals.messages.invalidUUID": "無效的UUID",
     "globals.messages.missingFields": "缺少字段：{name}",

internal/core/subscribers.go

@@ -34,7 +34,8 @@ func (c *Core) GetSubscriber(id int, uuid, email string) (models.Subscriber, err
 	}
 	if len(out) == 0 {
 		return models.Subscriber{}, echo.NewHTTPError(http.StatusBadRequest,
-			c.i18n.Ts("globals.messages.notFound", "name", "{globals.terms.subscriber}"))
+			c.i18n.Ts("globals.messages.notFound", "name",
+				fmt.Sprintf("{globals.terms.subscriber} (%d: %s%s)", id, uuid, email)))
 	}
 	if err := out.LoadLists(c.q.GetSubscriberListsLazy); err != nil {
 		c.log.Printf("error loading subscriber lists: %v", err)

models/models.go

@@ -347,6 +347,10 @@ type Bounce struct {
 
 // TxMessage represents an e-mail campaign.
 type TxMessage struct {
+	SubscriberEmails []string `json:"subscriber_emails"`
+	SubscriberIDs    []int    `json:"subscriber_ids"`
+
+	// Deprecated.
 	SubscriberEmail string `json:"subscriber_email"`
 	SubscriberID    int    `json:"subscriber_id"`