Files
libredesk/internal/inbox/channel/email/imap_test.go
2025-08-20 04:18:37 +05:30

124 lines
3.8 KiB
Go

package email
import (
"strings"
"testing"
"github.com/emersion/go-message/mail"
"github.com/jhillyerd/enmime"
)
// TestGoIMAPMessageIDParsing shows how go-imap fails to parse malformed Message-IDs
// and demonstrates the fallback solution.
// go-imap uses mail.Header.MessageID() which strictly follows RFC 5322 and returns
// empty strings for Message-IDs with multiple @ symbols.
//
// This caused emails to be dropped since we require Message-IDs for deduplication.
// References:
// - https://community.mailcow.email/d/701-multiple-at-in-message-id/5
// - https://github.com/emersion/go-message/issues/154#issuecomment-1425634946
func TestGoIMAPMessageIDParsing(t *testing.T) {
testCases := []struct {
input string
expectedIMAP string
expectedFallback string
name string
}{
{"<normal@example.com>", "normal@example.com", "normal@example.com", "normal message ID"},
{"<malformed@@example.com>", "", "malformed@@example.com", "double @ - IMAP fails, fallback works"},
{"<001c01d710db$a8137a50$f83a6ef0$@jones.smith@example.com>", "", "001c01d710db$a8137a50$f83a6ef0$@jones.smith@example.com", "mailcow-style - IMAP fails, fallback works"},
{"<test@@@domain.com>", "", "test@@@domain.com", "triple @ - IMAP fails, fallback works"},
{" <abc123@example.com> ", "abc123@example.com", "abc123@example.com", "with whitespace - both handle correctly"},
{"abc123@example.com", "", "abc123@example.com", "no angle brackets - IMAP fails, fallback works"},
{"", "", "", "empty input"},
{"<>", "", "", "empty brackets"},
{"<CAFnQjQFhY8z@mail.example.com@gateway.company.com>", "", "CAFnQjQFhY8z@mail.example.com@gateway.company.com", "gateway-style - IMAP fails, fallback works"},
}
for _, tc := range testCases {
t.Run(tc.name, func(t *testing.T) {
// Test go-imap parsing behavior
var h mail.Header
h.Set("Message-Id", tc.input)
imapResult, _ := h.MessageID()
if imapResult != tc.expectedIMAP {
t.Errorf("IMAP parsing of %q: expected %q, got %q", tc.input, tc.expectedIMAP, imapResult)
}
// Test fallback solution
if tc.input != "" {
rawEmail := "From: test@example.com\nMessage-ID: " + tc.input + "\n\nBody"
envelope, err := enmime.ReadEnvelope(strings.NewReader(rawEmail))
if err != nil {
t.Fatal(err)
}
fallbackResult := extractMessageIDFromHeaders(envelope)
if fallbackResult != tc.expectedFallback {
t.Errorf("Fallback extraction of %q: expected %q, got %q", tc.input, tc.expectedFallback, fallbackResult)
}
// Critical check: ensure fallback works when IMAP fails
if imapResult == "" && tc.expectedFallback != "" && fallbackResult == "" {
t.Errorf("CRITICAL: Both IMAP and fallback failed for %q - would drop email!", tc.input)
}
}
})
}
}
// TestEdgeCasesMessageID tests additional edge cases for Message-ID extraction.
func TestEdgeCasesMessageID(t *testing.T) {
tests := []struct {
name string
email string
expected string
}{
{
name: "no Message-ID header",
email: `From: test@example.com
To: inbox@test.com
Subject: Test
Body`,
expected: "",
},
{
name: "malformed header syntax",
email: `From: test@example.com
Message-ID: malformed-no-brackets@@domain.com
To: inbox@test.com
Body`,
expected: "malformed-no-brackets@@domain.com",
},
{
name: "multiple Message-ID headers (first wins)",
email: `From: test@example.com
Message-ID: <first@example.com>
Message-ID: <second@@example.com>
To: inbox@test.com
Body`,
expected: "first@example.com",
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
envelope, err := enmime.ReadEnvelope(strings.NewReader(tt.email))
if err != nil {
t.Fatal(err)
}
result := extractMessageIDFromHeaders(envelope)
if result != tt.expected {
t.Errorf("Expected %q, got %q", tt.expected, result)
}
})
}
}