enhancement(notifications): process ocm invites and sent out a mail notification

services/notifications/pkg/email/email.go

@@ -25,7 +25,7 @@ var (
 	imgDir = filepath.Join("templates", "html", "img")
 )
 
-// RenderEmailTemplate renders the email template for a new share
+// RenderEmailTemplate is responsible to prepare a message which than can be used to notify the user via email.
 func RenderEmailTemplate(mt MessageTemplate, locale, defaultLocale string, emailTemplatePath string, translationPath string, vars map[string]string) (*channels.Message, error) {
 	textMt, err := NewTextTemplate(mt, locale, defaultLocale, translationPath, vars)
 	if err != nil {

services/notifications/pkg/email/templates.go

@@ -72,18 +72,39 @@ You might still have access through your other groups or direct membership.`),
 
 Even though this membership has expired you still might have access through other shares and/or space memberships`),
 	}
+
+	ScienceMeshInviteTokenGenerated = MessageTemplate{
+		textTemplate: "templates/text/email.text.tmpl",
+		htmlTemplate: "templates/html/email.html.tmpl",
+		// ScienceMeshInviteTokenGenerated email template, Subject field (resolves directly)
+		Subject: l10n.Template(`ScienceMesh: {InitiatorName} wants to collaborate with you`),
+		// ScienceMeshInviteTokenGenerated email template, resolves via {{ .Greeting }}
+		Greeting: l10n.Template(`Hi,`),
+		// ScienceMeshInviteTokenGenerated email template, resolves via {{ .MessageBody }}
+		MessageBody: l10n.Template(`{ShareSharer} ({ShareSharerMail}) wants to start sharing OCM resources with you.
+{{if .ShareLink }}To accept the invite, please visit the following URL:
+{ShareLink}
+
+Alternatively, you can{{else}}
+Please{{end}} visit your mesh provider and use the following details:
+  Token: {Token}
+  ProviderDomain: {ProviderDomain}`),
+	}
 )
 
 // holds the information to turn the raw template into a parseable go template
 var _placeholders = map[string]string{
-	"{ShareSharer}":  "{{ .ShareSharer }}",
-	"{ShareFolder}":  "{{ .ShareFolder }}",
-	"{ShareGrantee}": "{{ .ShareGrantee }}",
-	"{ShareLink}":    "{{ .ShareLink }}",
-	"{SpaceName}":    "{{ .SpaceName }}",
-	"{SpaceGrantee}": "{{ .SpaceGrantee }}",
-	"{SpaceSharer}":  "{{ .SpaceSharer }}",
-	"{ExpiredAt}":    "{{ .ExpiredAt }}",
+	"{ShareSharer}":     "{{ .ShareSharer }}",
+	"{ShareFolder}":     "{{ .ShareFolder }}",
+	"{ShareGrantee}":    "{{ .ShareGrantee }}",
+	"{ShareLink}":       "{{ .ShareLink }}",
+	"{SpaceName}":       "{{ .SpaceName }}",
+	"{SpaceGrantee}":    "{{ .SpaceGrantee }}",
+	"{SpaceSharer}":     "{{ .SpaceSharer }}",
+	"{ExpiredAt}":       "{{ .ExpiredAt }}",
+	"{ShareSharerMail}": "{{ .ShareSharerMail }}",
+	"{ProviderDomain}":  "{{ .ProviderDomain }}",
+	"{Token}":           "{{ .Token }}",
 }
 
 // MessageTemplate is the data structure for the email

services/notifications/pkg/service/sciencemesh.go

@@ -1,9 +1,77 @@
 package service
 
 import (
+	"context"
+
 	"github.com/cs3org/reva/v2/pkg/events"
+	"github.com/cs3org/reva/v2/pkg/utils"
+	"github.com/owncloud/ocis/v2/services/notifications/pkg/channels"
+	"github.com/owncloud/ocis/v2/services/notifications/pkg/email"
 )
 
 func (s eventsNotifier) handleScienceMeshInviteTokenGenerated(e events.ScienceMeshInviteTokenGenerated) {
-	// fixMe: add implementation
+	logger := s.logger.With().
+		Str("event", "ScienceMeshInviteTokenGenerated").
+		Logger()
+
+	gatewayClient, err := s.gatewaySelector.Next()
+	if err != nil {
+		logger.Error().Err(err).Msg("could not select next gateway client")
+		return
+	}
+
+	ctx, err := utils.GetServiceUserContextWithContext(context.Background(), gatewayClient, s.serviceAccountID, s.serviceAccountSecret)
+	if err != nil {
+		logger.Error().Err(err).Msg("Could not impersonate service user")
+		return
+	}
+
+	owner, err := utils.GetUserWithContext(ctx, e.Sharer, gatewayClient)
+	if err != nil {
+		logger.Error().Err(err).Msg("unable to get user")
+		return
+	}
+
+	msgENV := map[string]string{
+		"ShareSharer":     owner.GetDisplayName(),
+		"ShareSharerMail": owner.GetMail(),
+		"ShareLink":       e.InviteLink,
+		"Token":           e.Token,
+		"ProviderDomain":  owner.GetId().GetIdp(),
+		"RecipientMail":   e.RecipientMail,
+	}
+
+	// validate the message, we only need recipient mail at the moment,
+	// event that is optional when the event got triggered...
+	// this means if we get a validation error, we can't send the message and skip it
+	{
+		validationEnv := make(map[string]interface{}, len(msgENV))
+		for k, v := range msgENV {
+			validationEnv[k] = v
+		}
+		if errs := validate.ValidateMap(validationEnv,
+			map[string]interface{}{
+				"RecipientMail": "required,email", // only recipient mail is required to send the message
+			}); len(errs) > 0 {
+			return // no mail, no message
+		}
+	}
+
+	msg, err := email.RenderEmailTemplate(
+		email.ScienceMeshInviteTokenGenerated,
+		s.defaultLanguage, // fixMe: the recipient is unknown, should it be the defaultLocale?,
+		s.defaultLanguage, // fixMe: the defaultLocale is not set by default, shouldn't it be?,
+		s.emailTemplatePath,
+		s.translationPath,
+		msgENV,
+	)
+	if err != nil {
+		s.logger.Error().Err(err).Msg("building the message has failed")
+		return
+	}
+
+	msg.Sender = owner.GetDisplayName()
+	msg.Recipient = []string{e.RecipientMail}
+
+	s.send(ctx, []*channels.Message{msg})
 }

services/notifications/pkg/service/service.go

@@ -16,6 +16,7 @@ import (
 	user "github.com/cs3org/go-cs3apis/cs3/identity/user/v1beta1"
 	rpc "github.com/cs3org/go-cs3apis/cs3/rpc/v1beta1"
 	provider "github.com/cs3org/go-cs3apis/cs3/storage/provider/v1beta1"
+	"github.com/go-playground/validator/v10"
 	"go-micro.dev/v4/metadata"
 	"google.golang.org/protobuf/types/known/fieldmaskpb"
 
@@ -30,6 +31,13 @@ import (
 	"github.com/owncloud/ocis/v2/services/settings/pkg/store/defaults"
 )
 
+// validate is the package level validator instance
+var validate *validator.Validate
+
+func init() {
+	validate = validator.New()
+}
+
 // Service should be named `Runner`
 type Service interface {
 	Run() error