Add http service to send email for shares

changelog/unreleased/mailer-shares.md

@@ -0,0 +1,3 @@
+Enhancement: Add http service to send email for shares
+
+https://github.com/cs3org/reva/pull/3304

internal/http/services/loader/loader.go

@@ -25,6 +25,7 @@ import (
 	_ "github.com/cs3org/reva/internal/http/services/datagateway"
 	_ "github.com/cs3org/reva/internal/http/services/dataprovider"
 	_ "github.com/cs3org/reva/internal/http/services/helloworld"
+	_ "github.com/cs3org/reva/internal/http/services/mailer"
 	_ "github.com/cs3org/reva/internal/http/services/mentix"
 	_ "github.com/cs3org/reva/internal/http/services/meshdirectory"
 	_ "github.com/cs3org/reva/internal/http/services/metrics"

internal/http/services/mailer/mailer.go

@@ -0,0 +1,378 @@
+// Copyright 2018-2021 CERN
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// In applying this license, CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+
+package mailer
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/smtp"
+	"os"
+	"path/filepath"
+	"strings"
+	"text/template"
+
+	gateway "github.com/cs3org/go-cs3apis/cs3/gateway/v1beta1"
+	group "github.com/cs3org/go-cs3apis/cs3/identity/group/v1beta1"
+	user "github.com/cs3org/go-cs3apis/cs3/identity/user/v1beta1"
+	rpc "github.com/cs3org/go-cs3apis/cs3/rpc/v1beta1"
+	collaboration "github.com/cs3org/go-cs3apis/cs3/sharing/collaboration/v1beta1"
+	provider "github.com/cs3org/go-cs3apis/cs3/storage/provider/v1beta1"
+	ctxpkg "github.com/cs3org/reva/pkg/ctx"
+	"github.com/cs3org/reva/pkg/errtypes"
+	"github.com/cs3org/reva/pkg/rgrpc/todo/pool"
+	"github.com/cs3org/reva/pkg/rhttp/global"
+	"github.com/cs3org/reva/pkg/sharedconf"
+	"github.com/mitchellh/mapstructure"
+	"github.com/rs/zerolog"
+)
+
+func init() {
+	global.Register("mailer", New)
+}
+
+type config struct {
+	SMTPAddress      string `mapstructure:"smtp_server" docs:";The hostname and port of the SMTP server."`
+	SenderLogin      string `mapstructure:"sender_login" docs:";The email to be used to send mails."`
+	SenderPassword   string `mapstructure:"sender_password" docs:";The sender's password."`
+	DisableAuth      bool   `mapstructure:"disable_auth" docs:"false;Whether to disable SMTP auth."`
+	Prefix           string `mapstructure:"prefix"`
+	BodyTemplatePath string `mapstructure:"body_template_path"`
+	SubjectTemplate  string `mapstructure:"subject_template"`
+	GatewaySVC       string `mapstructure:"gateway_svc"`
+}
+
+type svc struct {
+	conf    *config
+	client  gateway.GatewayAPIClient
+	tplBody *template.Template
+	tplSubj *template.Template
+}
+
+// New creates a new mailer service
+func New(m map[string]interface{}, log *zerolog.Logger) (global.Service, error) {
+	conf := &config{}
+	if err := mapstructure.Decode(m, conf); err != nil {
+		return nil, err
+	}
+
+	conf.init()
+
+	client, err := pool.GetGatewayServiceClient(pool.Endpoint(conf.GatewaySVC))
+	if err != nil {
+		return nil, err
+	}
+
+	s := &svc{
+		conf:   conf,
+		client: client,
+	}
+
+	if err = s.initBodyTemplate(); err != nil {
+		return nil, err
+	}
+	if err = s.initSubjectTemplate(); err != nil {
+		return nil, err
+	}
+
+	return s, nil
+}
+
+func (s *svc) Close() error {
+	return nil
+}
+
+func (s *svc) initBodyTemplate() error {
+	f, err := os.Open(s.conf.BodyTemplatePath)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	data, err := io.ReadAll(f)
+	if err != nil {
+		return err
+	}
+
+	tpl, err := template.New("tpl_body").Parse(string(data))
+	if err != nil {
+		return err
+	}
+
+	s.tplBody = tpl
+	return nil
+}
+
+func (s *svc) initSubjectTemplate() error {
+	tpl, err := template.New("tpl_subj").Parse(s.conf.SubjectTemplate)
+	if err != nil {
+		return err
+	}
+	s.tplSubj = tpl
+	return nil
+}
+
+func (c *config) init() {
+	if c.Prefix == "" {
+		c.Prefix = "mailer"
+	}
+
+	if c.SubjectTemplate == "" {
+		c.SubjectTemplate = "{{.OwnerName}} ({{.OwnerUsername}}) shared {{if .IsDir}}folder{{else}}file{{end}} '{{.Filename}}' with you"
+	}
+
+	c.GatewaySVC = sharedconf.GetGatewaySVC(c.GatewaySVC)
+}
+
+func (s *svc) Prefix() string {
+	return s.conf.Prefix
+}
+
+func (s *svc) Unprotected() []string {
+	return nil
+}
+
+type out struct {
+	Recipients []string `json:"recipients"`
+}
+
+func getIDsFromRequest(r *http.Request) ([]string, error) {
+	if err := r.ParseForm(); err != nil {
+		return nil, err
+	}
+
+	idsSet := make(map[string]struct{})
+
+	for _, id := range r.Form["id"] {
+		if _, ok := idsSet[id]; ok {
+			continue
+		}
+		idsSet[id] = struct{}{}
+	}
+
+	ids := make([]string, 0, len(idsSet))
+	for id := range idsSet {
+		ids = append(ids, id)
+	}
+
+	return ids, nil
+}
+
+func (s *svc) Handler() http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != http.MethodPost {
+			http.Error(w, http.StatusText(http.StatusMethodNotAllowed), http.StatusMethodNotAllowed)
+			return
+		}
+
+		ctx := r.Context()
+
+		ids, err := getIDsFromRequest(r)
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusBadRequest)
+		}
+
+		if len(ids) == 0 {
+			http.Error(w, "share id not provided", http.StatusBadRequest)
+			return
+		}
+
+		var recipients []string
+		for _, id := range ids {
+			recipient, err := s.sendMailForShare(ctx, id)
+			if err != nil {
+				http.Error(w, err.Error(), http.StatusInternalServerError)
+				return
+			}
+			recipients = append(recipients, recipient)
+		}
+
+		w.WriteHeader(http.StatusOK)
+		w.Header().Add("Content-Type", "application/json")
+		_ = json.NewEncoder(w).Encode(out{Recipients: recipients})
+	})
+}
+
+type shareInfo struct {
+	RecipientEmail    string
+	RecipientUsername string
+	OwnerEmail        string
+	OwnerName         string
+	OwnerUsername     string
+	ShareType         string
+	Filename          string
+	Path              string
+	IsDir             bool
+	ShareID           string
+}
+
+func (s *svc) getAuth() smtp.Auth {
+	if s.conf.DisableAuth {
+		return nil
+	}
+	return smtp.PlainAuth("", s.conf.SenderLogin, s.conf.SenderPassword, strings.SplitN(s.conf.SMTPAddress, ":", 2)[0])
+}
+
+func (s *svc) sendMailForShare(ctx context.Context, id string) (string, error) {
+	share, err := s.getShareInfoByID(ctx, id)
+	if err != nil {
+		return "", err
+	}
+
+	msg, err := s.generateMsg(share.OwnerEmail, share.RecipientEmail, share)
+	if err != nil {
+		return "", err
+	}
+
+	return share.RecipientEmail, smtp.SendMail(s.conf.SMTPAddress, s.getAuth(), share.OwnerEmail, []string{share.RecipientEmail}, msg)
+}
+
+func (s *svc) generateMsg(from, to string, share *shareInfo) ([]byte, error) {
+	subj, err := s.generateEmailSubject(share)
+	if err != nil {
+		return nil, err
+	}
+
+	body, err := s.generateEmailBody(share)
+	if err != nil {
+		return nil, err
+	}
+
+	msg := fmt.Sprintf("From: %s\r\n"+
+		"To: %s\r\n"+
+		"Subject: %s\r\n\r\n%s\r\n", from, to, subj, body)
+	return []byte(msg), nil
+}
+
+func (s *svc) getShareInfoByID(ctx context.Context, id string) (*shareInfo, error) {
+	user, ok := ctxpkg.ContextGetUser(ctx)
+	if !ok {
+		return nil, errtypes.UserRequired("user not in context")
+	}
+
+	shareRes, err := s.client.GetShare(ctx, &collaboration.GetShareRequest{
+		Ref: &collaboration.ShareReference{
+			Spec: &collaboration.ShareReference_Id{
+				Id: &collaboration.ShareId{
+					OpaqueId: id,
+				},
+			},
+		},
+	})
+
+	switch {
+	case err != nil:
+		return nil, err
+	case shareRes.Status.Code == rpc.Code_CODE_NOT_FOUND:
+		return nil, errtypes.NotFound(fmt.Sprintf("share %s not found", id))
+	case shareRes.Status.Code != rpc.Code_CODE_OK:
+		return nil, errtypes.InternalError(shareRes.Status.Message)
+	}
+
+	share := shareRes.Share
+	statRes, err := s.client.Stat(ctx, &provider.StatRequest{
+		Ref: &provider.Reference{
+			ResourceId: share.ResourceId,
+		},
+	})
+
+	switch {
+	case err != nil:
+		return nil, err
+	case statRes.Status.Code == rpc.Code_CODE_NOT_FOUND:
+		return nil, errtypes.NotFound("reference not found")
+	case statRes.Status.Code != rpc.Code_CODE_OK:
+		return nil, errtypes.InternalError(statRes.Status.Message)
+	}
+
+	file := statRes.Info
+
+	info := &shareInfo{}
+	switch g := share.Grantee.Id.(type) {
+	case *provider.Grantee_UserId:
+		grantee, err := s.getUser(ctx, g.UserId)
+		if err != nil {
+			return nil, err
+		}
+		info.RecipientEmail = grantee.Mail
+		info.RecipientUsername = grantee.Username
+		info.ShareType = "user"
+	case *provider.Grantee_GroupId:
+		grantee, err := s.getGroup(ctx, g.GroupId)
+		if err != nil {
+			return nil, err
+		}
+		info.RecipientEmail = grantee.Mail
+		info.RecipientUsername = grantee.GroupName
+		info.ShareType = "group"
+	}
+
+	info.OwnerEmail = user.Mail
+	info.OwnerName = user.DisplayName
+	info.OwnerUsername = user.Username
+
+	info.Path = file.Path
+	info.Filename = filepath.Base(file.Path)
+	if file.Type == provider.ResourceType_RESOURCE_TYPE_CONTAINER {
+		info.IsDir = true
+	} else {
+		info.IsDir = false
+	}
+
+	info.ShareID = id
+
+	return info, nil
+}
+
+func (s *svc) getUser(ctx context.Context, userID *user.UserId) (*user.User, error) {
+	res, err := s.client.GetUser(ctx, &user.GetUserRequest{
+		UserId: userID,
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	return res.User, nil
+}
+
+func (s *svc) getGroup(ctx context.Context, groupID *group.GroupId) (*group.Group, error) {
+	res, err := s.client.GetGroup(ctx, &group.GetGroupRequest{
+		GroupId: groupID,
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	return res.Group, nil
+}
+
+func (s *svc) generateEmailSubject(share *shareInfo) (string, error) {
+	var buf bytes.Buffer
+	err := s.tplSubj.Execute(&buf, share)
+	return buf.String(), err
+}
+
+func (s *svc) generateEmailBody(share *shareInfo) (string, error) {
+	var buf bytes.Buffer
+	err := s.tplBody.Execute(&buf, share)
+	return buf.String(), err
+}