package server import ( "bufio" "github.com/emersion/go-smtp" "github.com/stretchr/testify/require" "io" "net" "net/http" "strings" "testing" "time" ) func TestSmtpBackend_Multipart(t *testing.T) { email := `EHLO example.com MAIL FROM: phil@example.com RCPT TO: ntfy-mytopic@ntfy.sh DATA MIME-Version: 1.0 Date: Tue, 28 Dec 2021 00:30:10 +0100 Message-ID: Subject: and one more From: Phil To: ntfy-mytopic@ntfy.sh Content-Type: multipart/alternative; boundary="000000000000f3320b05d42915c9" --000000000000f3320b05d42915c9 Content-Type: text/plain; charset="UTF-8" what's up --000000000000f3320b05d42915c9 Content-Type: text/html; charset="UTF-8"
what's up

--000000000000f3320b05d42915c9-- . ` s, c, _, scanner := newTestSMTPServer(t, func(w http.ResponseWriter, r *http.Request) { require.Equal(t, "/mytopic", r.URL.Path) require.Equal(t, "and one more", r.Header.Get("Title")) require.Equal(t, "what's up", readAll(t, r.Body)) }) defer s.Close() defer c.Close() writeAndReadUntilLine(t, email, c, scanner, "250 2.0.0 OK: queued") } func TestSmtpBackend_MultipartNoBody(t *testing.T) { email := `EHLO example.com MAIL FROM: phil@example.com RCPT TO: ntfy-emailtest@ntfy.sh DATA MIME-Version: 1.0 Date: Tue, 28 Dec 2021 01:33:34 +0100 Message-ID: Subject: This email has a subject but no body From: Phil To: ntfy-emailtest@ntfy.sh Content-Type: multipart/alternative; boundary="000000000000bcf4a405d429f8d4" --000000000000bcf4a405d429f8d4 Content-Type: text/plain; charset="UTF-8" --000000000000bcf4a405d429f8d4 Content-Type: text/html; charset="UTF-8"

--000000000000bcf4a405d429f8d4-- . ` s, c, _, scanner := newTestSMTPServer(t, func(w http.ResponseWriter, r *http.Request) { require.Equal(t, "/emailtest", r.URL.Path) require.Equal(t, "", r.Header.Get("Title")) // We flipped message and body require.Equal(t, "This email has a subject but no body", readAll(t, r.Body)) }) defer s.Close() defer c.Close() writeAndReadUntilLine(t, email, c, scanner, "250 2.0.0 OK: queued") } func TestSmtpBackend_Plaintext(t *testing.T) { email := `EHLO example.com MAIL FROM: phil@example.com RCPT TO: mytopic@ntfy.sh DATA Date: Tue, 28 Dec 2021 00:30:10 +0100 Message-ID: Subject: and one more From: Phil To: mytopic@ntfy.sh Content-Type: text/plain; charset="UTF-8" what's up . ` s, c, conf, scanner := newTestSMTPServer(t, func(w http.ResponseWriter, r *http.Request) { require.Equal(t, "/mytopic", r.URL.Path) require.Equal(t, "and one more", r.Header.Get("Title")) require.Equal(t, "what's up", readAll(t, r.Body)) }) conf.SMTPServerAddrPrefix = "" defer s.Close() defer c.Close() writeAndReadUntilLine(t, email, c, scanner, "250 2.0.0 OK: queued") } func TestSmtpBackend_Plaintext_No_ContentType(t *testing.T) { email := `EHLO example.com MAIL FROM: phil@example.com RCPT TO: mytopic@ntfy.sh DATA Subject: Very short mail what's up . ` s, c, conf, scanner := newTestSMTPServer(t, func(w http.ResponseWriter, r *http.Request) { require.Equal(t, "/mytopic", r.URL.Path) require.Equal(t, "Very short mail", r.Header.Get("Title")) require.Equal(t, "what's up", readAll(t, r.Body)) }) conf.SMTPServerAddrPrefix = "" defer s.Close() defer c.Close() writeAndReadUntilLine(t, email, c, scanner, "250 2.0.0 OK: queued") } func TestSmtpBackend_Plaintext_EncodedSubject(t *testing.T) { email := `EHLO example.com MAIL FROM: phil@example.com RCPT TO: ntfy-mytopic@ntfy.sh DATA Date: Tue, 28 Dec 2021 00:30:10 +0100 Subject: =?UTF-8?B?VGhyZWUgc2FudGFzIPCfjoXwn46F8J+OhQ==?= From: Phil To: ntfy-mytopic@ntfy.sh Content-Type: text/plain; charset="UTF-8" what's up . ` s, c, _, scanner := newTestSMTPServer(t, func(w http.ResponseWriter, r *http.Request) { require.Equal(t, "Three santas 🎅🎅🎅", r.Header.Get("Title")) }) defer s.Close() defer c.Close() writeAndReadUntilLine(t, email, c, scanner, "250 2.0.0 OK: queued") } func TestSmtpBackend_Plaintext_TooLongTruncate(t *testing.T) { email := `EHLO example.com MAIL FROM: phil@example.com RCPT TO: mytopic@ntfy.sh DATA Date: Tue, 28 Dec 2021 00:30:10 +0100 Message-ID: Subject: and one more From: Phil To: mytopic@ntfy.sh Content-Type: text/plain; charset="UTF-8" you know this is a string. it's a long string. it's supposed to be longer than the max message length which is 4096 bytes, it used to be 512 bytes, but I increased that for the UnifiedPush support the 512 bytes was a little short, some people said but it kinda makes sense when you look at what it looks like one a phone heck this wasn't even half of it so far. so i'm gonna fill the rest of this with AAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAa AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp and with BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB that should do it . ` s, c, conf, scanner := newTestSMTPServer(t, func(w http.ResponseWriter, r *http.Request) { expected := `you know this is a string. it's a long string. it's supposed to be longer than the max message length which is 4096 bytes, it used to be 512 bytes, but I increased that for the UnifiedPush support the 512 bytes was a little short, some people said but it kinda makes sense when you look at what it looks like one a phone heck this wasn't even half of it so far. so i'm gonna fill the rest of this with AAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAa AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp pppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp and with BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB BBBBBBBBBBBBBBBBBBBBBBBBB` require.Equal(t, 4096, len(expected)) // Sanity check require.Equal(t, expected, readAll(t, r.Body)) }) defer s.Close() defer c.Close() conf.SMTPServerAddrPrefix = "" writeAndReadUntilLine(t, email, c, scanner, "250 2.0.0 OK: queued") } func TestSmtpBackend_Unsupported(t *testing.T) { email := `EHLO example.com MAIL FROM: phil@example.com RCPT TO: ntfy-mytopic@ntfy.sh DATA Date: Tue, 28 Dec 2021 00:30:10 +0100 Message-ID: Subject: and one more From: Phil To: mytopic@ntfy.sh Content-Type: text/SOMETHINGELSE what's up . ` s, c, _, scanner := newTestSMTPServer(t, func(w http.ResponseWriter, r *http.Request) { t.Fatal("This should not be called") }) defer s.Close() defer c.Close() writeAndReadUntilLine(t, email, c, scanner, "554 5.0.0 Error: transaction failed, blame it on the weather: unsupported content type") } func TestSmtpBackend_InvalidAddress(t *testing.T) { email := `EHLO example.com MAIL FROM: phil@example.com RCPT TO: unsupported@ntfy.sh DATA Date: Tue, 28 Dec 2021 00:30:10 +0100 Subject: and one more From: Phil To: mytopic@ntfy.sh Content-Type: text/plain what's up . ` s, c, _, scanner := newTestSMTPServer(t, func(w http.ResponseWriter, r *http.Request) { t.Fatal("This should not be called") }) defer s.Close() defer c.Close() writeAndReadUntilLine(t, email, c, scanner, "451 4.0.0 invalid address") } func TestSmtpBackend_Base64Body(t *testing.T) { email := `EHLO example.com MAIL FROM: test@mydomain.me RCPT TO: ntfy-mytopic@ntfy.sh DATA Content-Type: multipart/mixed; boundary="===============2138658284696597373==" MIME-Version: 1.0 Subject: TrueNAS truenas.local: TrueNAS Test Message hostname: truenas.local From: =?utf-8?q?Robbie?= To: test@mydomain.me Date: Thu, 16 Feb 2023 01:04:00 -0000 Message-ID: This is a multi-part message in MIME format. --===============2138658284696597373== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 VGhpcyBpcyBhIHRlc3QgbWVzc2FnZSBmcm9tIFRydWVOQVMgQ09SRS4= --===============2138658284696597373== Content-Type: text/html; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 PCFET0NUWVBFIEhUTUwgUFVCTElDICItLy9XM0MvL0RURCBIVE1MIDQuMCBUcmFuc2l0aW9uYWwv L0VOIj4KClRoaXMgaXMgYSB0ZXN0IG1lc3NhZ2UgZnJvbSBUcnVlTkFTIENPUkUuCg== --===============2138658284696597373==-- . ` s, c, _, scanner := newTestSMTPServer(t, func(w http.ResponseWriter, r *http.Request) { require.Equal(t, "/mytopic", r.URL.Path) require.Equal(t, "TrueNAS truenas.local: TrueNAS Test Message hostname: truenas.local", r.Header.Get("Title")) require.Equal(t, "This is a test message from TrueNAS CORE.", readAll(t, r.Body)) }) defer s.Close() defer c.Close() writeAndReadUntilLine(t, email, c, scanner, "250 2.0.0 OK: queued") } func TestSmtpBackend_NestedMultipartBase64(t *testing.T) { email := `EHLO example.com MAIL FROM: test@mydomain.me RCPT TO: ntfy-mytopic@ntfy.sh DATA Content-Type: multipart/mixed; boundary="===============2138658284696597373==" MIME-Version: 1.0 Subject: TrueNAS truenas.local: TrueNAS Test Message hostname: truenas.local From: =?utf-8?q?Robbie?= To: test@mydomain.me Date: Thu, 16 Feb 2023 01:04:00 -0000 Message-ID: This is a multi-part message in MIME format. --===============2138658284696597373== Content-Type: multipart/alternative; boundary="===============2233989480071754745==" MIME-Version: 1.0 --===============2233989480071754745== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 VGhpcyBpcyBhIHRlc3QgbWVzc2FnZSBmcm9tIFRydWVOQVMgQ09SRS4= --===============2233989480071754745== Content-Type: text/html; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 PCFET0NUWVBFIEhUTUwgUFVCTElDICItLy9XM0MvL0RURCBIVE1MIDQuMCBUcmFuc2l0aW9uYWwv L0VOIj4KClRoaXMgaXMgYSB0ZXN0IG1lc3NhZ2UgZnJvbSBUcnVlTkFTIENPUkUuCg== --===============2233989480071754745==-- --===============2138658284696597373==-- . ` s, c, _, scanner := newTestSMTPServer(t, func(w http.ResponseWriter, r *http.Request) { require.Equal(t, "/mytopic", r.URL.Path) require.Equal(t, "TrueNAS truenas.local: TrueNAS Test Message hostname: truenas.local", r.Header.Get("Title")) require.Equal(t, "This is a test message from TrueNAS CORE.", readAll(t, r.Body)) }) defer s.Close() defer c.Close() writeAndReadUntilLine(t, email, c, scanner, "250 2.0.0 OK: queued") } func TestSmtpBackend_NestedMultipartTooDeep(t *testing.T) { email := `EHLO example.com MAIL FROM: test@mydomain.me RCPT TO: ntfy-mytopic@ntfy.sh DATA Content-Type: multipart/mixed; boundary="===============1==" MIME-Version: 1.0 Subject: TrueNAS truenas.local: TrueNAS Test Message hostname: truenas.local From: =?utf-8?q?Robbie?= To: test@mydomain.me Date: Thu, 16 Feb 2023 01:04:00 -0000 Message-ID: This is a multi-part message in MIME format. --===============1== Content-Type: multipart/alternative; boundary="===============2==" MIME-Version: 1.0 --===============2== Content-Type: multipart/alternative; boundary="===============3==" MIME-Version: 1.0 --===============3== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 VGhpcyBpcyBhIHRlc3QgbWVzc2FnZSBmcm9tIFRydWVOQVMgQ09SRS4= --===============3== Content-Type: text/html; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 PCFET0NUWVBFIEhUTUwgUFVCTElDICItLy9XM0MvL0RURCBIVE1MIDQuMCBUcmFuc2l0aW9uYWwv L0VOIj4KClRoaXMgaXMgYSB0ZXN0IG1lc3NhZ2UgZnJvbSBUcnVlTkFTIENPUkUuCg== --===============3==-- --===============2==-- --===============1==-- . ` s, c, _, scanner := newTestSMTPServer(t, func(w http.ResponseWriter, r *http.Request) { t.Fatal("This should not be called") }) defer s.Close() defer c.Close() writeAndReadUntilLine(t, email, c, scanner, "554 5.0.0 Error: transaction failed, blame it on the weather: multipart message nested too deep") } func TestSmtpBackend_PlaintextWithToken(t *testing.T) { email := `EHLO example.com MAIL FROM: phil@example.com RCPT TO: ntfy-mytopic+tk_KLORUqSqvNRLpY11DfkHVbHu9NGG2@ntfy.sh DATA Subject: Very short mail what's up . ` s, c, _, scanner := newTestSMTPServer(t, func(w http.ResponseWriter, r *http.Request) { require.Equal(t, "/mytopic", r.URL.Path) require.Equal(t, "Very short mail", r.Header.Get("Title")) require.Equal(t, "Bearer tk_KLORUqSqvNRLpY11DfkHVbHu9NGG2", r.Header.Get("Authorization")) require.Equal(t, "what's up", readAll(t, r.Body)) }) defer s.Close() defer c.Close() writeAndReadUntilLine(t, email, c, scanner, "250 2.0.0 OK: queued") } type smtpHandlerFunc func(http.ResponseWriter, *http.Request) func newTestSMTPServer(t *testing.T, handler smtpHandlerFunc) (s *smtp.Server, c net.Conn, conf *Config, scanner *bufio.Scanner) { conf = newTestConfig(t) conf.SMTPServerListen = ":25" conf.SMTPServerDomain = "ntfy.sh" conf.SMTPServerAddrPrefix = "ntfy-" backend := newMailBackend(conf, handler) l, err := net.Listen("tcp", "127.0.0.1:0") if err != nil { t.Fatal(err) } s = smtp.NewServer(backend) s.Domain = conf.SMTPServerDomain s.AllowInsecureAuth = true go func() { require.Nil(t, s.Serve(l)) }() c, err = net.Dial("tcp", l.Addr().String()) if err != nil { t.Fatal(err) } scanner = bufio.NewScanner(c) return } func writeAndReadUntilLine(t *testing.T, email string, conn net.Conn, scanner *bufio.Scanner, expectedLine string) { _, err := io.WriteString(conn, email) require.Nil(t, err) readUntilLine(t, conn, scanner, expectedLine) } func readUntilLine(t *testing.T, conn net.Conn, scanner *bufio.Scanner, expectedLine string) { cancelChan := make(chan bool) go func() { select { case <-cancelChan: case <-time.After(3 * time.Second): conn.Close() t.Error("Failed waiting for expected output") } }() var output string for scanner.Scan() { text := scanner.Text() if strings.TrimSpace(text) == expectedLine { cancelChan <- true return } output += text + "\n" //fmt.Println(text) } t.Fatalf("Expected line '%s' not found in output:\n%s", expectedLine, output) }