GODT-1482: Comment or mitigate panics, unlock cache when needed.

internal/imap/mailbox_fetch.go

@@ -40,9 +40,9 @@ func (im *imapMailbox) getMessage(storeMessage storeMessageProvider, items []ima
 	for _, item := range items {
 		switch item {
 		case imap.FetchEnvelope:
-			// No need to check IsFullHeaderCached here. API header
-			// contain enough information to build the envelope.
-			msg.Envelope = message.GetEnvelope(m, storeMessage.GetMIMEHeader())
+			// No need to retrieve full header here. API header
+			// contains enough information to build the envelope.
+			msg.Envelope = message.GetEnvelope(m, storeMessage.GetMIMEHeaderFast())
 		case imap.FetchBody, imap.FetchBodyStructure:
 			structure, err := im.getBodyStructure(storeMessage)
 			if err != nil {
@@ -158,7 +158,10 @@ func (im *imapMailbox) getMessageBodySection(storeMessage storeMessageProvider,
 
 	isMainHeaderRequested := len(section.Path) == 0 && section.Specifier == imap.HeaderSpecifier
 	if isMainHeaderRequested && storeMessage.IsFullHeaderCached() {
-		header = storeMessage.GetHeader()
+		var err error
+		if header, err = storeMessage.GetHeader(); err != nil {
+			return nil, err
+		}
 	} else {
 		structure, bodyReader, err := im.getBodyAndStructure(storeMessage)
 		if err != nil {

internal/imap/mailbox_messages.go

@@ -383,8 +383,9 @@ func (im *imapMailbox) SearchMessages(isUID bool, criteria *imap.SearchCriteria)
 			}
 		}
 
-		// In order to speed up search it is not needed to check if IsFullHeaderCached.
-		header := storeMessage.GetMIMEHeader()
+		// In order to speed up search it is not needed to always
+		// retrieve the fully cached header.
+		header := storeMessage.GetMIMEHeaderFast()
 
 		if !criteria.SentBefore.IsZero() || !criteria.SentSince.IsZero() {
 			t, err := mail.Header(header).Date()

internal/imap/store.go

@@ -99,10 +99,10 @@ type storeMessageProvider interface {
 	Message() *pmapi.Message
 	IsMarkedDeleted() bool
 
-	GetHeader() []byte
+	GetHeader() ([]byte, error)
 	GetRFC822() ([]byte, error)
 	GetRFC822Size() (uint32, error)
-	GetMIMEHeader() textproto.MIMEHeader
+	GetMIMEHeaderFast() textproto.MIMEHeader
 	IsFullHeaderCached() bool
 	GetBodyStructure() (*pkgMsg.BodyStructure, error)
 }

internal/store/cache.go

@@ -21,8 +21,8 @@ import (
 	"context"
 
 	"github.com/ProtonMail/gopenpgp/v2/crypto"
+	"github.com/ProtonMail/proton-bridge/internal/store/cache"
 	"github.com/ProtonMail/proton-bridge/pkg/message"
-	"github.com/sirupsen/logrus"
 	bolt "go.etcd.io/bbolt"
 )
 
@@ -110,8 +110,15 @@ func SetBuildAndCacheJobLimit(maxJobs int) {
 }
 
 func (store *Store) getCachedMessage(messageID string) ([]byte, error) {
-	if store.cache.Has(store.user.ID(), messageID) {
-		return store.cache.Get(store.user.ID(), messageID)
+	if store.IsCached(messageID) {
+		literal, err := store.cache.Get(store.user.ID(), messageID)
+		if err == nil {
+			return literal, nil
+		}
+		store.log.
+			WithField("msg", messageID).
+			WithError(err).
+			Warn("Message is cached but cannot be retrieved")
 	}
 
 	job, done := store.newBuildJob(context.Background(), messageID, message.ForegroundPriority)
@@ -123,17 +130,43 @@ func (store *Store) getCachedMessage(messageID string) ([]byte, error) {
 	}
 
 	if !store.isMessageADraft(messageID) {
-		if err := store.cache.Set(store.user.ID(), messageID, literal); err != nil {
-			logrus.WithError(err).Error("Failed to cache message")
+		if err := store.writeToCacheUnlockIfFails(messageID, literal); err != nil {
+			store.log.WithError(err).Error("Failed to cache message")
 		}
+	} else {
+		store.log.Debug("Skipping cache draft message")
 	}
 
 	return literal, nil
 }
 
+func (store *Store) writeToCacheUnlockIfFails(messageID string, literal []byte) error {
+	err := store.cache.Set(store.user.ID(), messageID, literal)
+	if err == nil && err != cache.ErrCacheNeedsUnlock {
+		return err
+	}
+
+	kr, err := store.client().GetUserKeyRing()
+	if err != nil {
+		return err
+	}
+
+	if err := store.UnlockCache(kr); err != nil {
+		return err
+	}
+
+	return store.cache.Set(store.user.ID(), messageID, literal)
+}
+
 // IsCached returns whether the given message already exists in the cache.
-func (store *Store) IsCached(messageID string) bool {
-	return store.cache.Has(store.user.ID(), messageID)
+func (store *Store) IsCached(messageID string) (has bool) {
+	defer func() {
+		if r := recover(); r != nil {
+			store.log.WithField("recovered", r).Error("Cannot retrieve whether message exits, assuming no")
+		}
+	}()
+	has = store.cache.Has(store.user.ID(), messageID)
+	return
 }
 
 // BuildAndCacheMessage builds the given message (with background priority) and puts it in the cache.

internal/store/cache/disk.go

@@ -33,6 +33,7 @@ import (
 	"github.com/ricochet2200/go-disk-usage/du"
 )
 
+var ErrMsgCorrupted = errors.New("ecrypted file was corrupted")
 var ErrLowSpace = errors.New("not enough free space left on device")
 
 // IsOnDiskCache will return true if Cache is type of onDiskCache.
@@ -86,6 +87,10 @@ func NewOnDiskCache(path string, cmp Compressor, opts Options) (Cache, error) {
 	}, nil
 }
 
+func (c *onDiskCache) Lock(userID string) {
+	delete(c.gcm, userID)
+}
+
 func (c *onDiskCache) Unlock(userID string, passphrase []byte) error {
 	hash := sha256.New()
 
@@ -135,17 +140,29 @@ func (c *onDiskCache) Has(userID, messageID string) bool {
 		return false
 
 	default:
+		// Cannot decide whether the message is cached or not.
+		// Potential recover needs to be don in caller function.
 		panic(err)
 	}
 }
 
 func (c *onDiskCache) Get(userID, messageID string) ([]byte, error) {
+	gcm, ok := c.gcm[userID]
+	if !ok || gcm == nil {
+		return nil, ErrCacheNeedsUnlock
+	}
+
 	enc, err := c.readFile(c.getMessagePath(userID, messageID))
 	if err != nil {
 		return nil, err
 	}
 
-	cmp, err := c.gcm[userID].Open(nil, enc[:c.gcm[userID].NonceSize()], enc[c.gcm[userID].NonceSize():], nil)
+	// Data stored in file must larger than NonceSize.
+	if len(enc) <= gcm.NonceSize() {
+		return nil, ErrMsgCorrupted
+	}
+
+	cmp, err := gcm.Open(nil, enc[:gcm.NonceSize()], enc[gcm.NonceSize():], nil)
 	if err != nil {
 		return nil, err
 	}
@@ -154,7 +171,11 @@ func (c *onDiskCache) Get(userID, messageID string) ([]byte, error) {
 }
 
 func (c *onDiskCache) Set(userID, messageID string, literal []byte) error {
-	nonce := make([]byte, c.gcm[userID].NonceSize())
+	gcm, ok := c.gcm[userID]
+	if !ok {
+		return ErrCacheNeedsUnlock
+	}
+	nonce := make([]byte, gcm.NonceSize())
 
 	if _, err := rand.Read(nonce); err != nil {
 		return err
@@ -165,12 +186,13 @@ func (c *onDiskCache) Set(userID, messageID string, literal []byte) error {
 		return err
 	}
 
-	// NOTE(GODT-1158): How to properly handle low space? Don't return error, that's bad. Instead send event?
+	// NOTE(GODT-1158, GODT-1488): Need to properly handle low space. Don't
+	// return error, that's bad. Send event and clean least used message.
 	if !c.hasSpace(len(cmp)) {
 		return nil
 	}
 
-	return c.writeFile(c.getMessagePath(userID, messageID), c.gcm[userID].Seal(nonce, nonce, cmp, nil))
+	return c.writeFile(c.getMessagePath(userID, messageID), gcm.Seal(nonce, nonce, cmp, nil))
 }
 
 func (c *onDiskCache) Rem(userID, messageID string) error {

internal/store/cache/hash.go

@@ -26,6 +26,7 @@ func getHash(name string) string {
 	hash := sha256.New()
 
 	if _, err := hash.Write([]byte(name)); err != nil {
+		// sha256.Write always returns nill err so this should never happen
 		panic(err)
 	}
 

internal/store/cache/memory.go

@@ -28,7 +28,8 @@ type inMemoryCache struct {
 	size, limit int
 }
 
-// NewInMemoryCache creates a new in memory cache which stores up to the given number of bytes of cached data.
+// NewInMemoryCache creates a new in memory cache which stores up to the given
+// number of bytes of cached data.
 // NOTE(GODT-1158): Make this threadsafe.
 func NewInMemoryCache(limit int) Cache {
 	return &inMemoryCache{
@@ -42,7 +43,7 @@ func (c *inMemoryCache) Unlock(userID string, passphrase []byte) error {
 	return nil
 }
 
-func (c *inMemoryCache) Delete(userID string) error {
+func (c *inMemoryCache) Lock(userID string) {
 	c.lock.Lock()
 	defer c.lock.Unlock()
 
@@ -51,23 +52,44 @@ func (c *inMemoryCache) Delete(userID string) error {
 	}
 
 	delete(c.data, userID)
+}
 
+func (c *inMemoryCache) Delete(userID string) error {
+	c.Lock(userID)
 	return nil
 }
 
 // Has returns whether the given message exists in the cache.
 func (c *inMemoryCache) Has(userID, messageID string) bool {
-	if _, err := c.Get(userID, messageID); err != nil {
-		return false
+	c.lock.RLock()
+	defer c.lock.RUnlock()
+
+	if !c.isUserUnlocked(userID) {
+		// This might look counter intuitive but in order to be able to test
+		// "re-unlocking" mechanism we need to return true here.
+		//
+		// The situation is the same as it would happen for onDiskCache with
+		// locked user. Later during `Get` cache would return proper error
+		// `ErrCacheNeedsUnlock`. It is expected that store would then try to
+		// re-unlock.
+		//
+		// In order to do proper behaviour we should implement
+		// encryption for inMemoryCache.
+		return true
 	}
 
-	return true
+	_, ok := c.data[userID][messageID]
+	return ok
 }
 
 func (c *inMemoryCache) Get(userID, messageID string) ([]byte, error) {
 	c.lock.RLock()
 	defer c.lock.RUnlock()
 
+	if !c.isUserUnlocked(userID) {
+		return nil, ErrCacheNeedsUnlock
+	}
+
 	literal, ok := c.data[userID][messageID]
 	if !ok {
 		return nil, errors.New("no such message in cache")
@@ -76,12 +98,23 @@ func (c *inMemoryCache) Get(userID, messageID string) ([]byte, error) {
 	return literal, nil
 }
 
-// NOTE(GODT-1158): What to actually do when memory limit is reached? Replace something existing? Return error? Drop silently?
-// NOTE(GODT-1158): Pull in cache-rotating feature from old IMAP cache.
+func (c *inMemoryCache) isUserUnlocked(userID string) bool {
+	_, ok := c.data[userID]
+	return ok
+}
+
+// Set saves the message literal to memory for further usage.
+//
+// NOTE(GODT-1158, GODT-1488): Once memory limit is reached we should do proper
+// rotation based on usage frequency.
 func (c *inMemoryCache) Set(userID, messageID string, literal []byte) error {
 	c.lock.Lock()
 	defer c.lock.Unlock()
 
+	if !c.isUserUnlocked(userID) {
+		return ErrCacheNeedsUnlock
+	}
+
 	if c.size+len(literal) > c.limit {
 		return nil
 	}
@@ -96,6 +129,10 @@ func (c *inMemoryCache) Rem(userID, messageID string) error {
 	c.lock.Lock()
 	defer c.lock.Unlock()
 
+	if !c.isUserUnlocked(userID) {
+		return nil
+	}
+
 	c.size -= len(c.data[userID][messageID])
 
 	delete(c.data[userID], messageID)

internal/store/cache/types.go

@@ -17,8 +17,13 @@
 
 package cache
 
+import "errors"
+
+var ErrCacheNeedsUnlock = errors.New("cache needs to be unlocked")
+
 type Cache interface {
 	Unlock(userID string, passphrase []byte) error
+	Lock(userID string)
 	Delete(userID string) error
 
 	Has(userID, messageID string) bool

internal/store/cache_test.go

@@ -0,0 +1,122 @@
+// Copyright (c) 2022 Proton Technologies AG
+//
+// This file is part of ProtonMail Bridge.
+//
+// ProtonMail Bridge is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// ProtonMail Bridge is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with ProtonMail Bridge.  If not, see <https://www.gnu.org/licenses/>.
+
+package store
+
+import (
+	"testing"
+
+	"github.com/ProtonMail/proton-bridge/pkg/pmapi"
+	"github.com/golang/mock/gomock"
+	"github.com/stretchr/testify/require"
+)
+
+func TestIsCachedCrashRecovers(t *testing.T) {
+	r := require.New(t)
+	m, clear := initMocks(t)
+	defer clear()
+
+	m.newStoreNoEvents(t, true, &pmapi.Message{
+		ID:      "msg1",
+		Subject: "subject",
+	})
+
+	r.False(m.store.IsCached("msg1"))
+
+	m.store.cache = nil
+	r.False(m.store.IsCached("msg1"))
+}
+
+var wantLiteral = []byte("Mime-Version: 1.0\r\nContent-Transfer-Encoding: quoted-printable\r\nContent-Type: \r\nReferences:  <msg1@protonmail.internalid>\r\nX-Pm-Date: Thu, 01 Jan 1970 00:00:00 +0000\r\nX-Pm-External-Id: <>\r\nX-Pm-Internal-Id: msg1\r\nX-Original-Date: Mon, 01 Jan 0001 00:00:00 +0000\r\nDate: Fri, 13 Aug 1982 00:00:00 +0000\r\nMessage-Id: <msg1@protonmail.internalid>\r\nSubject: subject\r\n\r\n")
+
+func TestGetCachedMessageOK(t *testing.T) {
+	r := require.New(t)
+	m, clear := initMocks(t)
+	defer clear()
+
+	messageID := "msg1"
+
+	m.newStoreNoEvents(t, true, &pmapi.Message{
+		ID:      messageID,
+		Subject: "subject",
+		Flags:   pmapi.FlagReceived,
+		Body:    "body",
+	})
+
+	// Have build job
+	m.client.EXPECT().
+		KeyRingForAddressID(gomock.Any()).
+		Return(testPrivateKeyRing, nil).
+		Times(1)
+
+	haveLiteral, err := m.store.getCachedMessage(messageID)
+	r.NoError(err)
+	r.Equal(wantLiteral, haveLiteral)
+
+	r.True(m.store.IsCached(messageID))
+
+	// No build job
+	haveLiteral, err = m.store.getCachedMessage(messageID)
+	r.NoError(err)
+	r.Equal(wantLiteral, haveLiteral)
+	r.True(m.store.IsCached(messageID))
+}
+
+func TestGetCachedMessageCacheLocked(t *testing.T) {
+	r := require.New(t)
+	m, clear := initMocks(t)
+	defer clear()
+
+	messageID := "msg1"
+
+	m.newStoreNoEvents(t, true, &pmapi.Message{
+		ID:      messageID,
+		Subject: "subject",
+		Flags:   pmapi.FlagReceived,
+		Body:    "body",
+	})
+
+	// Have build job
+	m.client.EXPECT().
+		KeyRingForAddressID(gomock.Any()).
+		Return(testPrivateKeyRing, nil).
+		Times(1)
+	haveLiteral, err := m.store.getCachedMessage(messageID)
+	r.NoError(err)
+	r.Equal(wantLiteral, haveLiteral)
+	r.True(m.store.IsCached(messageID))
+
+	// Lock cache
+	m.store.cache.Lock(m.store.user.ID())
+
+	// Have build job again due to failure
+	m.client.EXPECT().
+		KeyRingForAddressID(gomock.Any()).
+		Return(testPrivateKeyRing, nil).
+		Times(1)
+
+	haveLiteral, err = m.store.getCachedMessage(messageID)
+	r.NoError(err)
+	r.Equal(wantLiteral, haveLiteral)
+	r.True(m.store.IsCached(messageID))
+
+	// No build job
+	haveLiteral, err = m.store.getCachedMessage(messageID)
+	r.NoError(err)
+	r.Equal(wantLiteral, haveLiteral)
+	r.True(m.store.IsCached(messageID))
+}

internal/store/cache_worker.go

@@ -67,6 +67,10 @@ func (cacher *MsgCachePool) newJob(messageID string) {
 }
 
 func (cacher *MsgCachePool) start() {
+	if cacher.started {
+		return
+	}
+
 	cacher.started = true
 
 	go func() {

internal/store/mailbox_ids.go

@@ -330,7 +330,9 @@ func (storeMailbox *Mailbox) txGetFinalUID(b *bolt.Bucket) uint32 {
 	uid, _ := b.Cursor().Last()
 
 	if uid == nil {
-		panic(errors.New("cannot get final UID of empty mailbox"))
+		// This happened most probably due to empty mailbox and whole
+		// store needs to be re-initialize in order to fix it.
+		panic(errors.New("cannot get final UID"))
 	}
 
 	return btoi(uid)

internal/store/main_test.go

@@ -25,7 +25,10 @@ import (
 
 func init() { //nolint[gochecknoinits]
 	logrus.SetLevel(logrus.ErrorLevel)
-	if os.Getenv("VERBOSITY") == "trace" {
+	switch os.Getenv("VERBOSITY") {
+	case "trace":
 		logrus.SetLevel(logrus.TraceLevel)
+	case "debug":
+		logrus.SetLevel(logrus.DebugLevel)
 	}
 }

internal/store/message.go

@@ -24,7 +24,6 @@ import (
 
 	pkgMsg "github.com/ProtonMail/proton-bridge/pkg/message"
 	"github.com/ProtonMail/proton-bridge/pkg/pmapi"
-	"github.com/pkg/errors"
 	bolt "go.etcd.io/bbolt"
 )
 
@@ -101,20 +100,42 @@ func (message *Message) getRawHeader() ([]byte, error) {
 }
 
 // GetHeader will return cached header from DB.
-func (message *Message) GetHeader() []byte {
+func (message *Message) GetHeader() ([]byte, error) {
 	raw, err := message.getRawHeader()
 	if err != nil {
-		panic(errors.Wrap(err, "failed to get raw message header"))
+		message.store.log.
+			WithField("msgID", message.ID()).
+			WithError(err).
+			Warn("Cannot get raw header")
+		return nil, err
 	}
 
-	return raw
+	return raw, nil
+}
+
+// GetMIMEHeaderFast returns full header if message was cached. If full header
+// is not available it will return header from metadata.
+// NOTE: Returned header may not contain all fields.
+func (message *Message) GetMIMEHeaderFast() (header textproto.MIMEHeader) {
+	var err error
+	if message.IsFullHeaderCached() {
+		header, err = message.GetMIMEHeader()
+	}
+	if header == nil || err != nil {
+		header = textproto.MIMEHeader(message.Message().Header)
+	}
+	return
 }
 
 // GetMIMEHeader will return cached header from DB, parsed as a textproto.MIMEHeader.
-func (message *Message) GetMIMEHeader() textproto.MIMEHeader {
+func (message *Message) GetMIMEHeader() (textproto.MIMEHeader, error) {
 	raw, err := message.getRawHeader()
 	if err != nil {
-		panic(errors.Wrap(err, "failed to get raw message header"))
+		message.store.log.
+			WithField("msgID", message.ID()).
+			WithError(err).
+			Warn("Cannot get raw header for MIME header")
+		return nil, err
 	}
 
 	header, err := textproto.NewReader(bufio.NewReader(bytes.NewReader(raw))).ReadMIMEHeader()
@@ -123,10 +144,10 @@ func (message *Message) GetMIMEHeader() textproto.MIMEHeader {
 			WithField("msgID", message.ID()).
 			WithError(err).
 			Warn("Cannot build header from bodystructure")
-		return textproto.MIMEHeader(message.msg.Header)
+		return nil, err
 	}
 
-	return header
+	return header, nil
 }
 
 // GetBodyStructure returns the message's body structure.

internal/store/store_test.go

@@ -187,7 +187,8 @@ func (mocks *mocksForStore) newStoreNoEvents(t *testing.T, combinedMode bool, ms
 
 	mocks.user.EXPECT().GetClient().AnyTimes().Return(mocks.client)
 
-	mocks.client.EXPECT().GetUserKeyRing().Return(tests.MakeKeyRing(t), nil).AnyTimes()
+	testUserKeyring := tests.MakeKeyRing(t)
+	mocks.client.EXPECT().GetUserKeyRing().Return(testUserKeyring, nil).AnyTimes()
 	mocks.client.EXPECT().Addresses().Return(pmapi.AddressList{
 		{ID: addrID1, Email: addr1, Type: pmapi.OriginalAddress, Receive: true},
 		{ID: addrID2, Email: addr2, Type: pmapi.AliasAddress, Receive: true},
@@ -225,6 +226,8 @@ func (mocks *mocksForStore) newStoreNoEvents(t *testing.T, combinedMode bool, ms
 	)
 	require.NoError(mocks.tb, err)
 
+	require.NoError(mocks.tb, mocks.store.UnlockCache(testUserKeyring))
+
 	// We want to wait until first sync has finished.
 	// Checking that event after sync was reuested is not the best way to
 	// do the check, because sync could take more time, but sync is going

internal/store/user_message_test.go

@@ -27,7 +27,6 @@ import (
 	pkgMsg "github.com/ProtonMail/proton-bridge/pkg/message"
 	"github.com/ProtonMail/proton-bridge/pkg/pmapi"
 	"github.com/golang/mock/gomock"
-	a "github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	bolt "go.etcd.io/bbolt"
 )
@@ -72,6 +71,7 @@ func TestGetMessageFromDB(t *testing.T) {
 }
 
 func TestCreateOrUpdateMessageMetadata(t *testing.T) {
+	r := require.New(t)
 	m, clear := initMocks(t)
 	defer clear()
 
@@ -79,33 +79,37 @@ func TestCreateOrUpdateMessageMetadata(t *testing.T) {
 	insertMessage(t, m, "msg1", "Test message 1", addrID1, false, []string{pmapi.AllMailLabel})
 
 	metadata, err := m.store.getMessageFromDB("msg1")
-	require.Nil(t, err)
+	r.NoError(err)
 
 	msg := &Message{msg: metadata, store: m.store, storeMailbox: nil}
 
 	// Check non-meta and calculated data are cleared/empty.
-	a.Equal(t, "", metadata.Body)
-	a.Equal(t, []*pmapi.Attachment(nil), metadata.Attachments)
-	a.Equal(t, "", metadata.MIMEType)
-	a.Equal(t, make(mail.Header), metadata.Header)
+	r.Equal("", metadata.Body)
+	r.Equal([]*pmapi.Attachment(nil), metadata.Attachments)
+	r.Equal("", metadata.MIMEType)
+	r.Equal(make(mail.Header), metadata.Header)
 
 	wantHeader, wantSize := putBodystructureAndSizeToDB(m, "msg1")
 
 	// Check cached data.
-	require.Nil(t, err)
-	a.Equal(t, wantHeader, msg.GetMIMEHeader())
+	haveHeader, err := msg.GetMIMEHeader()
+	r.NoError(err)
+	r.Equal(wantHeader, haveHeader)
+
 	haveSize, err := msg.GetRFC822Size()
-	require.Nil(t, err)
-	a.Equal(t, wantSize, haveSize)
+	r.NoError(err)
+	r.Equal(wantSize, haveSize)
 
 	// Check cached data are not overridden by reinsert.
 	insertMessage(t, m, "msg1", "Test message 1", addrID1, false, []string{pmapi.AllMailLabel})
 
-	require.Nil(t, err)
-	a.Equal(t, wantHeader, msg.GetMIMEHeader())
+	haveHeader, err = msg.GetMIMEHeader()
+	r.NoError(err)
+	r.Equal(wantHeader, haveHeader)
+
 	haveSize, err = msg.GetRFC822Size()
-	require.Nil(t, err)
-	a.Equal(t, wantSize, haveSize)
+	r.NoError(err)
+	r.Equal(wantSize, haveSize)
 }
 
 func TestDeleteMessage(t *testing.T) {