PDF not possible to be viewed in the browser

[phsc84]

Describe the bug
PDFs should have the option to be viewed in the browser or to be downloaded.

PDF with no option to be viewed in the browser
----boundary_2799_4e1e27b0-e322-4f60-97c3-45bf9cd8e113
Content-Type: application/octet-stream; name="2022-000182500_a.pdf"
Content-Transfer-Encoding: base64
Content-Disposition: attachment
X-EC0D2A8E-5CB7-4969-9C36-46D859D137BE-PartID: {A7EC3E57-0EE9-40EC-821A-16B5CC8340DF}

PDF with option to be viewed in the browser
--b66120d3-6d65-4e54-a6cb-f7dfb8e086a1-1
Content-Type: application/pdf;
name="180717_factsheet.pdf"
Content-Disposition: attachment;
filename="180717_factsheet.pdf"
Content-Transfer-Encoding: base64

Please complete the following information:

• Browser: Chrome 109
• PHP version: 8.1
• SnappyMail Version: 2.24.5

Additional context
The problem does not exist in SnappyMail 2.22.5.

[the-djmaze]

Strange as this was fixed in your #144 issue.

I have one email that has

Content-Type: application/octet-stream; name=20210420.pdf
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename=20210420.pdf

And it does open properly in my browser.

You can modify the following code and hope to find the issue.

snappymail/snappymail/v/0.0.0/app/libraries/RainLoop/Actions/Raw.php

Lines 147 to 154 in 974adb7

	// https://github.com/the-djmaze/snappymail/issues/144
	if ('.pdf' === \substr($sFileNameIn,-4)) {
	$sContentTypeOut = 'application/pdf'; // application/octet-stream
	} else {
	$sContentTypeOut = $sContentTypeIn
	?: \SnappyMail\File\MimeType::fromFilename($sFileNameIn)
	?: 'application/octet-stream';
	}

Maybe start with something like:

// https://github.com/the-djmaze/snappymail/issues/144
if ('.pdf' === \substr($sFileNameIn,-4)) {
	$sContentTypeOut = 'application/pdf'; // application/octet-stream
error_log("Output {$sFileNameIn} forced PDF");
} else {
	$sContentTypeOut = $sContentTypeIn
		?: \SnappyMail\File\MimeType::fromFilename($sFileNameIn)
		?: 'application/octet-stream';
error_log("Output {$sFileNameIn} as {$sContentTypeOut}");
}

[phsc84]

I've modified the file Raw.php and added the code you suggested. Unfortunately, nothing popped up in the logs, even with log level 7 (=debug).

Then I've modified the file as follows, because I wanted to be sure, that the program enters the if (!empty($sFileHashIn)) {.

error_log("ContentTypeIn {$sContentTypeIn} FileNameIn {$sFileNameIn} FileHashIn {$sFileHashIn}");

		if (!empty($sFileHashIn)) {
			$this->verifyCacheByKey($sRawKey);

// https://github.com/the-djmaze/snappymail/issues/144
if ('.pdf' === \substr($sFileNameIn,-4)) {
	$sContentTypeOut = 'application/pdf'; // application/octet-stream
error_log("Output {$sFileNameIn} forced PDF");
} else {
	$sContentTypeOut = $sContentTypeIn
		?: \SnappyMail\File\MimeType::fromFilename($sFileNameIn)
		?: 'application/octet-stream';
error_log("Output {$sFileNameIn} as {$sContentTypeOut}");
}

But even with that I don't get any log output. Strange...

Do you have an idea what else I could try?

[the-djmaze]

I've overlooked that there is another part a bit lower.
Maybe that is triggered and fails.

snappymail/snappymail/v/0.0.0/app/libraries/RainLoop/Actions/Raw.php

Lines 197 to 206 in 974adb7

	if ('.pdf' === \substr($sFileName, -4)) {
	// https://github.com/the-djmaze/snappymail/issues/144
	$sContentType = 'application/pdf';
	} else {
	$sContentType = $sContentTypeIn
	?: $sContentType
	// ?: \SnappyMail\File\MimeType::fromStream($rResource, $sFileName)
	?: \SnappyMail\File\MimeType::fromFilename($sFileName)
	?: 'application/octet-stream';
	}

[phsc84]

Even if I add the error_log statements in this part, I don't get any logs. When activating the debug mode, I get the following, but I doubt, this will help much...
[2023-01-20 21:02:22.062][241e27d1] IMAP[INFO]: < * 18 FETCH (UID 13507 RFC822.SIZE 86893 INTERNALDATE "17-Jan-2023 10:02:23 +0100" FLAGS (\Seen $Forwarded) BODYSTRUCTURE ((("text" "html" ("charset" "utf-8") NIL NIL "base64" 19118 245 NIL NIL NIL NIL)("application" "octet-stream" ("name" "2022-000182500_a.pdf") NIL NIL "base64" 53606 NIL ("attachment" NIL) NIL NIL) "mixed" ("boundary" "--boundary_2799_4e1e27b0-e322-4f60-97c3-45bf9cd8e113") NIL NIL NIL)("application" "pkcs7-signature" ("name" "smime.p7s") NIL NIL "base64" 10994 NIL ("attachment" ("filename" "smime.p7s")) NIL NIL) "signed" ("protocol" "application/pkcs7-signature" "micalg" "sha-256" "boundary" "----A0EA02B57E456D7764E38D2EDBEA7E15") NIL NIL NIL) BODY[HEADER.FIELDS (RETURN-PATH RECEIVED MIME-VERSION MESSAGE-ID CONTENT-TYPE FROM TO CC BCC SENDER REPLY-TO DELIVERED-TO IN-REPLY-TO REFERENCES DATE SUBJECT X-MSMAIL-PRIORITY IMPORTANCE X-PRIORITY X-DRAFT-INFO RETURN-RECEIPT-TO DISPOSITION-NOTIFICATION-TO X-CONFIRM-READING-TO AUTHENTICATION-RESULTS X-DKIM-AUTHENTICATION-RESULTS LIST-UNSUBSCRIBE AUTOCRYPT X-SPAM-STATUS X-SPAMD-RESULT X-BOGOSITY X-VIRUS X-VIRUS-SCANNED X-VIRUS-STATUS)] {1553}\r\n

[phsc84]

My Raw.php file (had to rename it to Raw.txt in order to upload it) meanwhile looks as follows, but I don't get any output in the log (log level 4, debug mode activated).
Raw.txt

[the-djmaze]

I've made a change to better log it.

Use that and disable cache in application.ini / Admin -> Config
Then it should properly log info and hopefully disable browser cache.

[phsc84]

Wonderful, now I get log output. It shows the following:
[2023-01-22 10:12:55.288][3aecbea3] RAW[DEBUG]: Array
(
[0] => 2022-000182500_a.pdf
[1] => application/octet-stream
[2] =>
[3] => application/octet-stream
)

[the-djmaze]

I think i found the issue with above commit.

[phsc84]

Fantastic! I've applied the patch and now it works like a charm again. Thank you very much!