Charset is not set when I attach a Text/plain attachment

[chibenwa]

Description

Twake mail do not set charset when sending a text attachment.

Charset should always be set because otherwise many problem arise.

Actual behaviour

MIME-Version: 1.0
Subject: Test
From: Benoit TELLIER <[email protected]>
To: =?ISO-8859-1?Q?Beno=EEt_TELLIER?= <[email protected]>
Date: Tue, 13 Feb 2024 23:01:18 +0000
Message-ID: <[email protected]>
Content-Type: multipart/mixed;
 boundary="-=Part.17f.732e3d28e1c76db4.18da4b40791.62ef5e3fa995057d=-"

---=Part.17f.732e3d28e1c76db4.18da4b40791.62ef5e3fa995057d=-
Content-Type: multipart/alternative;
 boundary="-=Part.17e.48ac92d73c356567.18da4b40791.360a293e2f389efe=-"

---=Part.17e.48ac92d73c356567.18da4b40791.360a293e2f389efe=-
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: quoted-printable

Test

---=Part.17e.48ac92d73c356567.18da4b40791.360a293e2f389efe=-
Content-Type: text/html; charset=UTF-8
Content-Transfer-Encoding: quoted-printable

<div>Test<br><br></div>

---=Part.17e.48ac92d73c356567.18da4b40791.360a293e2f389efe=---

---=Part.17f.732e3d28e1c76db4.18da4b40791.62ef5e3fa995057d=-
Content-Type: text/plain; name="=?US-ASCII?Q?id=5Frsa.txt?="
Content-Disposition: attachment
Content-Transfer-Encoding: base64
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==

Expected behaviour

MIME-Version: 1.0
Subject: Test
From: Benoit TELLIER <[email protected]>
To: =?ISO-8859-1?Q?Beno=EEt_TELLIER?= <[email protected]>
Date: Tue, 13 Feb 2024 23:01:18 +0000
Message-ID: <[email protected]>
Content-Type: multipart/mixed;
 boundary="-=Part.17f.732e3d28e1c76db4.18da4b40791.62ef5e3fa995057d=-"

---=Part.17f.732e3d28e1c76db4.18da4b40791.62ef5e3fa995057d=-
Content-Type: multipart/alternative;
 boundary="-=Part.17e.48ac92d73c356567.18da4b40791.360a293e2f389efe=-"

---=Part.17e.48ac92d73c356567.18da4b40791.360a293e2f389efe=-
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: quoted-printable

Test

---=Part.17e.48ac92d73c356567.18da4b40791.360a293e2f389efe=-
Content-Type: text/html; charset=UTF-8
Content-Transfer-Encoding: quoted-printable

<div>Test<br><br></div>

---=Part.17e.48ac92d73c356567.18da4b40791.360a293e2f389efe=---

---=Part.17f.732e3d28e1c76db4.18da4b40791.62ef5e3fa995057d=-
Content-Type: text/plain; name="=?US-ASCII?Q?id=5Frsa.txt?=" charset=PLATEFORM-CHARSET
Content-Disposition: attachment
Content-Transfer-Encoding: base64
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==

Where PLATEFORM-CHARSET is for instance UTF-8

[hoangdat]

Can we hardcode UTF-8 ? or detect it directly from file?

[chibenwa]

Do you have access to OS default?

How hard to detect it?

[dab246]

IMO, detecting it from file is most accurate

[hoangdat]

IMO, detecting it from file is most accurate

but it takes time and a lot of memory consumption when reading file byte.

[dab246]

We will use UriData of dart:core. It will only take less memory to store at the time of parsing.

[chibenwa]

We will use UriData of dart:core. It will only take less memory to store at the time of parsing.

Looks great! just check it's not too bad perf wise ;-)