Rebase branch for upstream changes through 1.0.2

.build.yml

@@ -0,0 +1,19 @@
+image: alpine/edge
+packages:
+  - go
+  # Required by codecov
+  - bash
+  - findutils
+sources:
+  - https://github.com/emersion/go-imap
+tasks:
+  - build: |
+      cd go-imap
+      go build -v ./...
+  - test: |
+      cd go-imap
+      go test -coverprofile=coverage.txt -covermode=atomic ./...
+  - upload-coverage: |
+      cd go-imap
+      export CODECOV_TOKEN=8c0f7014-fcfa-4ed9-8972-542eb5958fb3
+      curl -s https://codecov.io/bash | bash

README.md

@@ -1,44 +1,34 @@
 # go-imap
 
-[![GoDoc](https://godoc.org/github.com/emersion/go-imap?status.svg)](https://godoc.org/github.com/emersion/go-imap)
+[![GoDoc](https://godoc.org/github.com/mailgun/go-imap?status.svg)](https://godoc.org/github.com/mailgun/go-imap)
 [![Build Status](https://travis-ci.org/emersion/go-imap.svg?branch=master)](https://travis-ci.org/emersion/go-imap)
 [![Codecov](https://codecov.io/gh/emersion/go-imap/branch/master/graph/badge.svg)](https://codecov.io/gh/emersion/go-imap)
 [![Go Report
-Card](https://goreportcard.com/badge/github.com/emersion/go-imap)](https://goreportcard.com/report/github.com/emersion/go-imap)
+Card](https://goreportcard.com/badge/github.com/mailgun/go-imap)](https://goreportcard.com/report/github.com/mailgun/go-imap)
 [![Unstable](https://img.shields.io/badge/stability-unstable-yellow.svg)](https://github.com/emersion/stability-badges#unstable)
 [![Gitter chat](https://badges.gitter.im/goimap/Lobby.svg)](https://gitter.im/goimap/Lobby)
+>>>>>>> cf144a2... Moving to use go mod
 
 An [IMAP4rev1](https://tools.ietf.org/html/rfc3501) library written in Go. It
 can be used to build a client and/or a server.
 
 ```bash
-go get github.com/emersion/go-imap/...
+go get github.com/mailgun/go-imap/...
+>>>>>>> cf144a2... Moving to use go mod
 ```
 
-## Why?
-
-Other IMAP implementations in Go:
-* Require to make [many type assertions or conversions](https://github.com/emersion/neutron/blob/ca635850e2223d6cfe818664ef901fa6e3c1d859/backend/imap/util.go#L110)
-* Are not idiomatic or are [ugly](https://github.com/jordwest/imap-server/blob/master/conn/commands.go#L53)
-* Are [not pleasant to use](https://github.com/emersion/neutron/blob/ca635850e2223d6cfe818664ef901fa6e3c1d859/backend/imap/messages.go#L228)
-* Implement a server _xor_ a client, not both
-* Don't implement unilateral updates (i.e. the server can't notify clients for
-  new messages)
-* Do not have a good test coverage
-* Don't handle encoding and charset automatically
-
 ## Usage
 
-### Client [![GoDoc](https://godoc.org/github.com/emersion/go-imap/client?status.svg)](https://godoc.org/github.com/emersion/go-imap/client)
+### Client [![GoDoc](https://godoc.org/github.com/mailgun/go-imap/client?status.svg)](https://godoc.org/github.com/mailgun/go-imap/client)
 
 ```go
 package main
 
 import (
 	"log"
 
-	"github.com/emersion/go-imap/client"
-	"github.com/emersion/go-imap"
+	"github.com/mailgun/go-imap/client"
+	"github.com/mailgun/go-imap"
 )
 
 func main() {
@@ -96,7 +86,7 @@ func main() {
 	messages := make(chan *imap.Message, 10)
 	done = make(chan error, 1)
 	go func() {
-		done <- c.Fetch(seqset, []string{imap.EnvelopeMsgAttr}, messages)
+		done <- c.Fetch(seqset, []imap.FetchItem{imap.FetchEnvelope}, messages)
 	}()
 
 	log.Println("Last 4 messages:")
@@ -112,16 +102,16 @@ func main() {
 }
 ```
 
-### Server [![GoDoc](https://godoc.org/github.com/emersion/go-imap/server?status.svg)](https://godoc.org/github.com/emersion/go-imap/server)
+### Server [![GoDoc](https://godoc.org/github.com/mailgun/go-imap/server?status.svg)](https://godoc.org/github.com/mailgun/go-imap/server)
 
 ```go
 package main
 
 import (
 	"log"
 
-	"github.com/emersion/go-imap/server"
-	"github.com/emersion/go-imap/backend/memory"
+	"github.com/mailgun/go-imap/server"
+	"github.com/mailgun/go-imap/backend/memory"
 )
 
 func main() {
@@ -149,34 +139,35 @@ You can now use `telnet localhost 1143` to manually connect to the server.
 ### Extensions
 
 Commands defined in IMAP extensions are available in other packages. See [the
-wiki](https://github.com/emersion/go-imap/wiki/Using-extensions#using-client-extensions)
+wiki](https://github.com/mailgun/go-imap/wiki/Using-extensions#using-client-extensions)
 to learn how to use them.
 
-* [APPENDLIMIT](https://github.com/emersion/go-imap-appendlimit)
-* [COMPRESS](https://github.com/emersion/go-imap-compress)
-* [ENABLE](https://github.com/emersion/go-imap-enable)
+* [APPENDLIMIT](https://github.com/mailgun/go-imap-appendlimit)
+* [COMPRESS](https://github.com/mailgun/go-imap-compress)
+* [ENABLE](https://github.com/mailgun/go-imap-enable)
 * [ID](https://github.com/ProtonMail/go-imap-id)
-* [IDLE](https://github.com/emersion/go-imap-idle)
-* [MOVE](https://github.com/emersion/go-imap-move)
-* [QUOTA](https://github.com/emersion/go-imap-quota)
-* [SPECIAL-USE](https://github.com/emersion/go-imap-specialuse)
-* [UNSELECT](https://github.com/emersion/go-imap-unselect)
-* [UIDPLUS](https://github.com/emersion/go-imap-uidplus)
+* [IDLE](https://github.com/mailgun/go-imap-idle)
+* [MOVE](https://github.com/mailgun/go-imap-move)
+* [QUOTA](https://github.com/mailgun/go-imap-quota)
+* [SORT and THREAD](https://github.com/mailgun/go-imap-sortthread)
+* [SPECIAL-USE](https://github.com/mailgun/go-imap-specialuse)
+* [UNSELECT](https://github.com/mailgun/go-imap-unselect)
+* [UIDPLUS](https://github.com/mailgun/go-imap-uidplus)
 
 ### Server backends
 
-* [Memory](https://github.com/emersion/go-imap/tree/master/backend/memory) (for testing)
-* [Multi](https://github.com/emersion/go-imap-multi)
-* [PGP](https://github.com/emersion/go-imap-pgp)
-* [Proxy](https://github.com/emersion/go-imap-proxy)
+* [Memory](https://github.com/mailgun/go-imap/tree/master/backend/memory) (for testing)
+* [Multi](https://github.com/mailgun/go-imap-multi)
+* [PGP](https://github.com/mailgun/go-imap-pgp)
+* [Proxy](https://github.com/mailgun/go-imap-proxy)
 
 ### Related projects
 
 * [go-message](https://github.com/emersion/go-message) - parsing and formatting MIME and mail messages
+* [go-msgauth](https://github.com/emersion/go-msgauth) - handle DKIM, DMARC and Authentication-Results
 * [go-pgpmail](https://github.com/emersion/go-pgpmail) - decrypting and encrypting mails with OpenPGP
 * [go-sasl](https://github.com/emersion/go-sasl) - sending and receiving SASL authentications
 * [go-smtp](https://github.com/emersion/go-smtp) - building SMTP clients and servers
-* [go-dkim](https://github.com/emersion/go-dkim) - creating and verifying DKIM signatures
 
 ## License
 

backend/backend.go

@@ -1,7 +1,11 @@
 // Package backend defines an IMAP server backend interface.
 package backend
 
-import "errors"
+import (
+	"errors"
+
+	"github.com/mailgun/go-imap"
+)
 
 // ErrInvalidCredentials is returned by Backend.Login when a username or a
 // password is incorrect.
@@ -12,5 +16,5 @@ var ErrInvalidCredentials = errors.New("Invalid credentials")
 type Backend interface {
 	// Login authenticates a user. If the username or the password is incorrect,
 	// it returns ErrInvalidCredentials.
-	Login(username, password string) (User, error)
+	Login(connInfo *imap.ConnInfo, username, password string) (User, error)
 }

backend/backendutil/backendutil_test.go

@@ -8,20 +8,55 @@ var testDate, _ = time.Parse(time.RFC1123Z, "Sat, 18 Jun 2016 12:00:00 +0900")
 
 const testHeaderString = "Content-Type: multipart/mixed; boundary=message-boundary\r\n" +
 	"Date: Sat, 18 Jun 2016 12:00:00 +0900\r\n" +
+	"Date: Sat, 19 Jun 2016 12:00:00 +0900\r\n" +
 	"From: Mitsuha Miyamizu <mitsuha.miyamizu@example.org>\r\n" +
+	"Reply-To: Mitsuha Miyamizu <mitsuha.miyamizu+replyto@example.org>\r\n" +
 	"Message-Id: 42@example.org\r\n" +
 	"Subject: Your Name.\r\n" +
 	"To: Taki Tachibana <taki.tachibana@example.org>\r\n" +
 	"\r\n"
 
+const testHeaderFromToString = "From: Mitsuha Miyamizu <mitsuha.miyamizu@example.org>\r\n" +
+	"To: Taki Tachibana <taki.tachibana@example.org>\r\n" +
+	"\r\n"
+
+const testHeaderDateString = "Date: Sat, 18 Jun 2016 12:00:00 +0900\r\n" +
+	"Date: Sat, 19 Jun 2016 12:00:00 +0900\r\n" +
+	"\r\n"
+
+const testHeaderNoFromToString = "Content-Type: multipart/mixed; boundary=message-boundary\r\n" +
+	"Date: Sat, 18 Jun 2016 12:00:00 +0900\r\n" +
+	"Date: Sat, 19 Jun 2016 12:00:00 +0900\r\n" +
+	"Reply-To: Mitsuha Miyamizu <mitsuha.miyamizu+replyto@example.org>\r\n" +
+	"Message-Id: 42@example.org\r\n" +
+	"Subject: Your Name.\r\n" +
+	"\r\n"
+
+const testAltHeaderString = "Content-Type: multipart/alternative; boundary=b2\r\n" +
+	"\r\n"
+
 const testTextHeaderString = "Content-Disposition: inline\r\n" +
 	"Content-Type: text/plain\r\n" +
 	"\r\n"
 
+const testTextContentTypeString = "Content-Type: text/plain\r\n" +
+	"\r\n"
+
+const testTextNoContentTypeString = "Content-Disposition: inline\r\n" +
+	"\r\n"
+
 const testTextBodyString = "What's your name?"
 
 const testTextString = testTextHeaderString + testTextBodyString
 
+const testHTMLHeaderString = "Content-Disposition: inline\r\n" +
+	"Content-Type: text/html\r\n" +
+	"\r\n"
+
+const testHTMLBodyString = "<div>What's <i>your</i> name?</div>"
+
+const testHTMLString = testHTMLHeaderString + testHTMLBodyString
+
 const testAttachmentHeaderString = "Content-Disposition: attachment; filename=note.txt\r\n" +
 	"Content-Type: text/plain\r\n" +
 	"\r\n"
@@ -31,7 +66,12 @@ const testAttachmentBodyString = "My name is Mitsuha."
 const testAttachmentString = testAttachmentHeaderString + testAttachmentBodyString
 
 const testBodyString = "--message-boundary\r\n" +
+	testAltHeaderString +
+	"\r\n--b2\r\n" +
 	testTextString +
+	"\r\n--b2\r\n" +
+	testHTMLString +
+	"\r\n--b2--\r\n" +
 	"\r\n--message-boundary\r\n" +
 	testAttachmentString +
 	"\r\n--message-boundary--\r\n"

backend/backendutil/body.go

@@ -4,21 +4,43 @@ import (
 	"bytes"
 	"errors"
 	"io"
+	"mime"
+	nettextproto "net/textproto"
+	"strings"
 
-	"github.com/emersion/go-imap"
-	"github.com/emersion/go-message"
+	"github.com/emersion/go-message/textproto"
+	"github.com/mailgun/go-imap"
 )
 
 var errNoSuchPart = errors.New("backendutil: no such message body part")
 
+func multipartReader(header textproto.Header, body io.Reader) *textproto.MultipartReader {
+	contentType := header.Get("Content-Type")
+	if !strings.HasPrefix(strings.ToLower(contentType), "multipart/") {
+		return nil
+	}
+
+	_, params, err := mime.ParseMediaType(contentType)
+	if err != nil {
+		return nil
+	}
+
+	return textproto.NewMultipartReader(body, params["boundary"])
+}
+
 // FetchBodySection extracts a body section from a message.
-func FetchBodySection(e *message.Entity, section *imap.BodySectionName) (imap.Literal, error) {
+func FetchBodySection(header textproto.Header, body io.Reader, section *imap.BodySectionName) (imap.Literal, error) {
 	// First, find the requested part using the provided path
-	for i := len(section.Path) - 1; i >= 0; i-- {
+	for i := 0; i < len(section.Path); i++ {
 		n := section.Path[i]
 
-		mr := e.MultipartReader()
+		mr := multipartReader(header, body)
 		if mr == nil {
+			// First part of non-multipart message refers to the message itself.
+			// See RFC 3501, Page 55.
+			if len(section.Path) == 1 && section.Path[0] == 1 {
+				break
+			}
 			return nil, errNoSuchPart
 		}
 
@@ -31,7 +53,9 @@ func FetchBodySection(e *message.Entity, section *imap.BodySectionName) (imap.Li
 			}
 
 			if j == n {
-				e = p
+				body = p
+				header = p.Header
+
 				break
 			}
 		}
@@ -40,22 +64,51 @@ func FetchBodySection(e *message.Entity, section *imap.BodySectionName) (imap.Li
 	// Then, write the requested data to a buffer
 	b := new(bytes.Buffer)
 
+	resHeader := header
+	if section.Fields != nil {
+		// Copy header so we will not change value passed to us.
+		resHeader = header.Copy()
+
+		if section.NotFields {
+			for _, fieldName := range section.Fields {
+				resHeader.Del(fieldName)
+			}
+		} else {
+			fieldsMap := make(map[string]struct{}, len(section.Fields))
+			for _, field := range section.Fields {
+				fieldsMap[nettextproto.CanonicalMIMEHeaderKey(field)] = struct{}{}
+			}
+
+			for field := resHeader.Fields(); field.Next(); {
+				if _, ok := fieldsMap[field.Key()]; !ok {
+					field.Del()
+				}
+			}
+		}
+	}
+
 	// Write the header
-	mw, err := message.CreateWriter(b, e.Header)
+	err := textproto.WriteHeader(b, resHeader)
 	if err != nil {
 		return nil, err
 	}
-	defer mw.Close()
 
-	// If the header hasn't been requested, discard it
-	if section.Specifier == imap.TextSpecifier {
+	switch section.Specifier {
+	case imap.TextSpecifier:
+		// The header hasn't been requested. Discard it.
 		b.Reset()
+	case imap.EntireSpecifier:
+		if len(section.Path) > 0 {
+			// When selecting a specific part by index, IMAP servers
+			// return only the text, not the associated MIME header.
+			b.Reset()
+		}
 	}
 
 	// Write the body, if requested
 	switch section.Specifier {
 	case imap.EntireSpecifier, imap.TextSpecifier:
-		if _, err := io.Copy(mw, e.Body); err != nil {
+		if _, err := io.Copy(b, body); err != nil {
 			return nil, err
 		}
 	}