mirror of
https://github.com/chatmail/core.git
synced 2026-04-05 23:22:11 +03:00
810be4f6c7
this PR fixes a bug that lowercases all links handleld by `dehtml()`, which is wrong. closes #5361
545 lines
18 KiB
Rust
545 lines
18 KiB
Rust
//! De-HTML.
|
|
//!
|
|
//! A module to remove HTML tags from the email text
|
|
|
|
use std::io::BufRead;
|
|
|
|
use once_cell::sync::Lazy;
|
|
use quick_xml::{
|
|
events::{BytesEnd, BytesStart, BytesText},
|
|
Reader,
|
|
};
|
|
|
|
use crate::simplify::{simplify_quote, SimplifiedText};
|
|
|
|
struct Dehtml {
|
|
strbuilder: String,
|
|
quote: String,
|
|
add_text: AddText,
|
|
last_href: Option<String>,
|
|
/// GMX wraps a quote in `<div name="quote">`. After a `<div name="quote">`, this count is
|
|
/// increased at each `<div>` and decreased at each `</div>`. This way we know when the quote ends.
|
|
/// If this is > `0`, then we are inside a `<div name="quote">`
|
|
divs_since_quote_div: u32,
|
|
/// Everything between `<div name="quote">` and `<div name="quoted-content">` is usually metadata
|
|
/// If this is > `0`, then we are inside a `<div name="quoted-content">`.
|
|
divs_since_quoted_content_div: u32,
|
|
/// All-Inkl just puts the quote into `<blockquote> </blockquote>`. This count is
|
|
/// increased at each `<blockquote>` and decreased at each `</blockquote>`.
|
|
blockquotes_since_blockquote: u32,
|
|
}
|
|
|
|
impl Dehtml {
|
|
/// Returns true if HTML parser is currently inside the quote.
|
|
fn is_quote(&self) -> bool {
|
|
self.divs_since_quoted_content_div > 0 || self.blockquotes_since_blockquote > 0
|
|
}
|
|
|
|
/// Returns the buffer where the text should be written.
|
|
///
|
|
/// If the parser is inside the quote, returns the quote buffer.
|
|
fn get_buf(&mut self) -> &mut String {
|
|
if self.is_quote() {
|
|
&mut self.quote
|
|
} else {
|
|
&mut self.strbuilder
|
|
}
|
|
}
|
|
|
|
fn get_add_text(&self) -> AddText {
|
|
if self.divs_since_quote_div > 0 && self.divs_since_quoted_content_div == 0 {
|
|
AddText::No // Everything between `<div name="quoted">` and `<div name="quoted_content">` is metadata which we don't want
|
|
} else {
|
|
self.add_text
|
|
}
|
|
}
|
|
}
|
|
|
|
#[derive(Debug, PartialEq, Clone, Copy)]
|
|
enum AddText {
|
|
/// Inside `<script>`, `<style>` and similar tags
|
|
/// which contents should not be displayed.
|
|
No,
|
|
|
|
YesRemoveLineEnds,
|
|
|
|
/// Inside `<pre>`.
|
|
YesPreserveLineEnds,
|
|
}
|
|
|
|
pub(crate) fn dehtml(buf: &str) -> Option<SimplifiedText> {
|
|
let (s, quote) = dehtml_quick_xml(buf);
|
|
if !s.trim().is_empty() {
|
|
let text = dehtml_cleanup(s);
|
|
let top_quote = if !quote.trim().is_empty() {
|
|
Some(dehtml_cleanup(simplify_quote("e).0))
|
|
} else {
|
|
None
|
|
};
|
|
return Some(SimplifiedText {
|
|
text,
|
|
top_quote,
|
|
..Default::default()
|
|
});
|
|
}
|
|
let s = dehtml_manually(buf);
|
|
if !s.trim().is_empty() {
|
|
let text = dehtml_cleanup(s);
|
|
return Some(SimplifiedText {
|
|
text,
|
|
..Default::default()
|
|
});
|
|
}
|
|
None
|
|
}
|
|
|
|
fn dehtml_cleanup(mut text: String) -> String {
|
|
text.retain(|c| c != '\r');
|
|
let lines = text.trim().split('\n');
|
|
let mut text = String::new();
|
|
let mut linebreak = false;
|
|
for line in lines {
|
|
if line.chars().all(char::is_whitespace) {
|
|
linebreak = true;
|
|
} else {
|
|
if !text.is_empty() {
|
|
text += "\n";
|
|
if linebreak {
|
|
text += "\n";
|
|
}
|
|
}
|
|
text += line.trim_end();
|
|
linebreak = false;
|
|
}
|
|
}
|
|
text
|
|
}
|
|
|
|
fn dehtml_quick_xml(buf: &str) -> (String, String) {
|
|
let buf = buf.trim().trim_start_matches("<!doctype html>");
|
|
|
|
let mut dehtml = Dehtml {
|
|
strbuilder: String::with_capacity(buf.len()),
|
|
quote: String::new(),
|
|
add_text: AddText::YesRemoveLineEnds,
|
|
last_href: None,
|
|
divs_since_quote_div: 0,
|
|
divs_since_quoted_content_div: 0,
|
|
blockquotes_since_blockquote: 0,
|
|
};
|
|
|
|
let mut reader = quick_xml::Reader::from_str(buf);
|
|
reader.check_end_names(false);
|
|
|
|
let mut buf = Vec::new();
|
|
|
|
loop {
|
|
match reader.read_event_into(&mut buf) {
|
|
Ok(quick_xml::events::Event::Start(ref e)) => {
|
|
dehtml_starttag_cb(e, &mut dehtml, &reader)
|
|
}
|
|
Ok(quick_xml::events::Event::End(ref e)) => dehtml_endtag_cb(e, &mut dehtml),
|
|
Ok(quick_xml::events::Event::Text(ref e)) => dehtml_text_cb(e, &mut dehtml),
|
|
Ok(quick_xml::events::Event::CData(e)) => match e.escape() {
|
|
Ok(e) => dehtml_text_cb(&e, &mut dehtml),
|
|
Err(e) => {
|
|
eprintln!(
|
|
"CDATA escape error at position {}: {:?}",
|
|
reader.buffer_position(),
|
|
e,
|
|
);
|
|
}
|
|
},
|
|
Ok(quick_xml::events::Event::Empty(ref e)) => {
|
|
// Handle empty tags as a start tag immediately followed by end tag.
|
|
// For example, `<p/>` is treated as `<p></p>`.
|
|
dehtml_starttag_cb(e, &mut dehtml, &reader);
|
|
dehtml_endtag_cb(
|
|
&BytesEnd::new(String::from_utf8_lossy(e.name().as_ref())),
|
|
&mut dehtml,
|
|
);
|
|
}
|
|
Err(e) => {
|
|
eprintln!(
|
|
"Parse html error: Error at position {}: {:?}",
|
|
reader.buffer_position(),
|
|
e
|
|
);
|
|
}
|
|
Ok(quick_xml::events::Event::Eof) => break,
|
|
_ => (),
|
|
}
|
|
buf.clear();
|
|
}
|
|
|
|
(dehtml.strbuilder, dehtml.quote)
|
|
}
|
|
|
|
fn dehtml_text_cb(event: &BytesText, dehtml: &mut Dehtml) {
|
|
static LINE_RE: Lazy<regex::Regex> = Lazy::new(|| regex::Regex::new(r"(\r?\n)+").unwrap());
|
|
|
|
if dehtml.get_add_text() == AddText::YesPreserveLineEnds
|
|
|| dehtml.get_add_text() == AddText::YesRemoveLineEnds
|
|
{
|
|
let event = event as &[_];
|
|
let event_str = std::str::from_utf8(event).unwrap_or_default();
|
|
let mut last_added = escaper::decode_html_buf_sloppy(event).unwrap_or_default();
|
|
if event_str.starts_with(&last_added) {
|
|
last_added = event_str.to_string();
|
|
}
|
|
|
|
if dehtml.get_add_text() == AddText::YesRemoveLineEnds {
|
|
// Replace all line ends with spaces.
|
|
// E.g. `\r\n\r\n` is replaced with one space.
|
|
let last_added = LINE_RE.replace_all(&last_added, " ");
|
|
|
|
// Add a space if `last_added` starts with a space
|
|
// and there is no whitespace at the end of the buffer yet.
|
|
// Trim the rest of leading whitespace from `last_added`.
|
|
let buf = dehtml.get_buf();
|
|
if !buf.ends_with(' ') && !buf.ends_with('\n') && last_added.starts_with(' ') {
|
|
*buf += " ";
|
|
}
|
|
|
|
*buf += last_added.trim_start();
|
|
} else {
|
|
*dehtml.get_buf() += LINE_RE.replace_all(&last_added, "\n").as_ref();
|
|
}
|
|
}
|
|
}
|
|
|
|
fn dehtml_endtag_cb(event: &BytesEnd, dehtml: &mut Dehtml) {
|
|
let tag = String::from_utf8_lossy(event.name().as_ref())
|
|
.trim()
|
|
.to_lowercase();
|
|
|
|
match tag.as_str() {
|
|
"style" | "script" | "title" | "pre" => {
|
|
*dehtml.get_buf() += "\n\n";
|
|
dehtml.add_text = AddText::YesRemoveLineEnds;
|
|
}
|
|
"div" => {
|
|
pop_tag(&mut dehtml.divs_since_quote_div);
|
|
pop_tag(&mut dehtml.divs_since_quoted_content_div);
|
|
|
|
*dehtml.get_buf() += "\n\n";
|
|
dehtml.add_text = AddText::YesRemoveLineEnds;
|
|
}
|
|
"a" => {
|
|
if let Some(ref last_href) = dehtml.last_href.take() {
|
|
let buf = dehtml.get_buf();
|
|
if buf.ends_with('[') {
|
|
buf.truncate(buf.len() - 1);
|
|
} else {
|
|
*buf += "](";
|
|
*buf += last_href;
|
|
*buf += ")";
|
|
}
|
|
}
|
|
}
|
|
"b" | "strong" => {
|
|
if dehtml.get_add_text() != AddText::No {
|
|
*dehtml.get_buf() += "*";
|
|
}
|
|
}
|
|
"i" | "em" => {
|
|
if dehtml.get_add_text() != AddText::No {
|
|
*dehtml.get_buf() += "_";
|
|
}
|
|
}
|
|
"blockquote" => pop_tag(&mut dehtml.blockquotes_since_blockquote),
|
|
_ => {}
|
|
}
|
|
}
|
|
|
|
fn dehtml_starttag_cb<B: std::io::BufRead>(
|
|
event: &BytesStart,
|
|
dehtml: &mut Dehtml,
|
|
reader: &quick_xml::Reader<B>,
|
|
) {
|
|
let tag = String::from_utf8_lossy(event.name().as_ref())
|
|
.trim()
|
|
.to_lowercase();
|
|
|
|
match tag.as_str() {
|
|
"p" | "table" | "td" => {
|
|
if !dehtml.strbuilder.is_empty() {
|
|
*dehtml.get_buf() += "\n\n";
|
|
}
|
|
dehtml.add_text = AddText::YesRemoveLineEnds;
|
|
}
|
|
#[rustfmt::skip]
|
|
"div" => {
|
|
maybe_push_tag(event, reader, "quote", &mut dehtml.divs_since_quote_div);
|
|
maybe_push_tag(event, reader, "quoted-content", &mut dehtml.divs_since_quoted_content_div);
|
|
|
|
*dehtml.get_buf() += "\n\n";
|
|
dehtml.add_text = AddText::YesRemoveLineEnds;
|
|
}
|
|
"br" => {
|
|
*dehtml.get_buf() += "\n";
|
|
dehtml.add_text = AddText::YesRemoveLineEnds;
|
|
}
|
|
"style" | "script" | "title" => {
|
|
dehtml.add_text = AddText::No;
|
|
}
|
|
"pre" => {
|
|
*dehtml.get_buf() += "\n\n";
|
|
dehtml.add_text = AddText::YesPreserveLineEnds;
|
|
}
|
|
"a" => {
|
|
if let Some(href) = event
|
|
.html_attributes()
|
|
.filter_map(|attr| attr.ok())
|
|
.find(|attr| {
|
|
String::from_utf8_lossy(attr.key.as_ref())
|
|
.trim()
|
|
.to_lowercase()
|
|
== "href"
|
|
})
|
|
{
|
|
let href = href
|
|
.decode_and_unescape_value(reader)
|
|
.unwrap_or_default()
|
|
.to_string();
|
|
|
|
if !href.is_empty() {
|
|
dehtml.last_href = Some(href);
|
|
*dehtml.get_buf() += "[";
|
|
}
|
|
}
|
|
}
|
|
"b" | "strong" => {
|
|
if dehtml.get_add_text() != AddText::No {
|
|
*dehtml.get_buf() += "*";
|
|
}
|
|
}
|
|
"i" | "em" => {
|
|
if dehtml.get_add_text() != AddText::No {
|
|
*dehtml.get_buf() += "_";
|
|
}
|
|
}
|
|
"blockquote" => dehtml.blockquotes_since_blockquote += 1,
|
|
_ => {}
|
|
}
|
|
}
|
|
|
|
/// In order to know when a specific tag is closed, we need to count the opening and closing tags.
|
|
/// The `counts`s are stored in the `Dehtml` struct.
|
|
fn pop_tag(count: &mut u32) {
|
|
if *count > 0 {
|
|
*count -= 1;
|
|
}
|
|
}
|
|
|
|
/// In order to know when a specific tag is closed, we need to count the opening and closing tags.
|
|
/// The `counts`s are stored in the `Dehtml` struct.
|
|
fn maybe_push_tag(
|
|
event: &BytesStart,
|
|
reader: &Reader<impl BufRead>,
|
|
tag_name: &str,
|
|
count: &mut u32,
|
|
) {
|
|
if *count > 0 || tag_contains_attr(event, reader, tag_name) {
|
|
*count += 1;
|
|
}
|
|
}
|
|
|
|
fn tag_contains_attr(event: &BytesStart, reader: &Reader<impl BufRead>, name: &str) -> bool {
|
|
event.attributes().any(|r| {
|
|
r.map(|a| {
|
|
a.decode_and_unescape_value(reader)
|
|
.map(|v| v == name)
|
|
.unwrap_or(false)
|
|
})
|
|
.unwrap_or(false)
|
|
})
|
|
}
|
|
|
|
pub fn dehtml_manually(buf: &str) -> String {
|
|
// Just strip out everything between "<" and ">"
|
|
let mut strbuilder = String::new();
|
|
let mut show_next_chars = true;
|
|
for c in buf.chars() {
|
|
match c {
|
|
'<' => show_next_chars = false,
|
|
'>' => show_next_chars = true,
|
|
_ => {
|
|
if show_next_chars {
|
|
strbuilder.push(c)
|
|
}
|
|
}
|
|
}
|
|
}
|
|
strbuilder
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use super::*;
|
|
|
|
#[test]
|
|
fn test_dehtml() {
|
|
let cases = vec",
|
|
),
|
|
("<b> bar </b>", "* bar *"),
|
|
("<i>foo</i>", "_foo_"),
|
|
("<b> bar <i> foo", "* bar _ foo"),
|
|
("& bar", "& bar"),
|
|
// Despite missing ', this should be shown:
|
|
("<a href='/foo.png>Hi</a> ", "Hi"),
|
|
("No link: <a href='https://get.delta.chat/'/>", "No link:"),
|
|
(
|
|
"No link: <a href='https://get.delta.chat/'></a>",
|
|
"No link:",
|
|
),
|
|
("<!doctype html>\n<b>fat text</b>", "*fat text*"),
|
|
// Invalid html (at least DC should show the text if the html is invalid):
|
|
("<!some invalid html code>\n<b>some text</b>", "some text"),
|
|
];
|
|
for (input, output) in cases {
|
|
assert_eq!(dehtml(input).unwrap().text, output);
|
|
}
|
|
let none_cases = vec!["<html> </html>", ""];
|
|
for input in none_cases {
|
|
assert_eq!(dehtml(input), None);
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn test_dehtml_parse_br() {
|
|
let html = "line1<br>line2";
|
|
let plain = dehtml(html).unwrap().text;
|
|
assert_eq!(plain, "line1\nline2");
|
|
|
|
let html = "line1<br> line2";
|
|
let plain = dehtml(html).unwrap().text;
|
|
assert_eq!(plain, "line1\nline2");
|
|
|
|
let html = "line1 <br><br> line2";
|
|
let plain = dehtml(html).unwrap().text;
|
|
assert_eq!(plain, "line1\n\nline2");
|
|
|
|
let html = "\r\r\nline1<br>\r\n\r\n\r\rline2<br/>line3\n\r";
|
|
let plain = dehtml(html).unwrap().text;
|
|
assert_eq!(plain, "line1\nline2\nline3");
|
|
}
|
|
|
|
#[test]
|
|
fn test_dehtml_parse_span() {
|
|
assert_eq!(dehtml("<span>Foo</span>bar").unwrap().text, "Foobar");
|
|
assert_eq!(dehtml("<span>Foo</span> bar").unwrap().text, "Foo bar");
|
|
assert_eq!(dehtml("<span>Foo </span>bar").unwrap().text, "Foo bar");
|
|
assert_eq!(dehtml("<span>Foo</span>\nbar").unwrap().text, "Foo bar");
|
|
assert_eq!(dehtml("\n<span>Foo</span> bar").unwrap().text, "Foo bar");
|
|
assert_eq!(dehtml("<span>Foo</span>\n\nbar").unwrap().text, "Foo bar");
|
|
assert_eq!(dehtml("Foo\n<span>bar</span>").unwrap().text, "Foo bar");
|
|
assert_eq!(dehtml("Foo<span>\nbar</span>").unwrap().text, "Foo bar");
|
|
}
|
|
|
|
#[test]
|
|
fn test_dehtml_parse_p() {
|
|
let html = "<p>Foo</p><p>Bar</p>";
|
|
let plain = dehtml(html).unwrap().text;
|
|
assert_eq!(plain, "Foo\n\nBar");
|
|
|
|
let html = "<p>Foo<p>Bar";
|
|
let plain = dehtml(html).unwrap().text;
|
|
assert_eq!(plain, "Foo\n\nBar");
|
|
|
|
let html = "<p>Foo</p><p>Bar<p>Baz";
|
|
let plain = dehtml(html).unwrap().text;
|
|
assert_eq!(plain, "Foo\n\nBar\n\nBaz");
|
|
}
|
|
|
|
#[test]
|
|
fn test_dehtml_parse_href() {
|
|
let html = "<a href=url>text</a";
|
|
let plain = dehtml(html).unwrap().text;
|
|
|
|
assert_eq!(plain, "[text](url)");
|
|
}
|
|
|
|
#[test]
|
|
fn test_dehtml_case_sensitive_link() {
|
|
let html = "<html><A HrEf=\"https://foo.bar/Data\">case in URLs matter</A></html>";
|
|
let plain = dehtml(html).unwrap().text;
|
|
assert_eq!(plain, "[case in URLs matter](https://foo.bar/Data)");
|
|
}
|
|
|
|
#[test]
|
|
fn test_dehtml_bold_text() {
|
|
let html = "<!DOCTYPE name [<!DOCTYPE ...>]><!-- comment -->text <b><?php echo ... ?>bold</b><![CDATA[<>]]>";
|
|
let plain = dehtml(html).unwrap().text;
|
|
|
|
assert_eq!(plain, "text *bold*<>");
|
|
}
|
|
|
|
#[test]
|
|
fn test_dehtml_html_encoded() {
|
|
let html =
|
|
"<>"'& äÄöÖüÜß fooÆçÇ ♦‎‏‌&noent;‍";
|
|
|
|
let plain = dehtml(html).unwrap().text;
|
|
|
|
assert_eq!(
|
|
plain,
|
|
"<>\"\'& äÄöÖüÜß fooÆçÇ \u{2666}\u{200e}\u{200f}\u{200c}&noent;\u{200d}"
|
|
);
|
|
}
|
|
|
|
#[test]
|
|
fn test_unclosed_tags() {
|
|
let input = r##"
|
|
<!DOCTYPE HTML PUBLIC '-//W3C//DTD HTML 4.01 Transitional//EN'
|
|
'http://www.w3.org/TR/html4/loose.dtd'>
|
|
<html>
|
|
<head>
|
|
<title>Hi</title>
|
|
<meta http-equiv='Content-Type' content='text/html; charset=iso-8859-1'>
|
|
</head>
|
|
<body>
|
|
lots of text
|
|
</body>
|
|
</html>
|
|
"##;
|
|
let txt = dehtml(input).unwrap();
|
|
assert_eq!(txt.text.trim(), "lots of text");
|
|
}
|
|
|
|
#[test]
|
|
fn test_pre_tag() {
|
|
let input = "<html><pre>\ntwo\nlines\n</pre></html>";
|
|
let txt = dehtml(input).unwrap();
|
|
assert_eq!(txt.text.trim(), "two\nlines");
|
|
}
|
|
|
|
#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
|
|
async fn test_quote_div() {
|
|
let input = include_str!("../test-data/message/gmx-quote-body.eml");
|
|
let dehtml = dehtml(input).unwrap();
|
|
let SimplifiedText {
|
|
text,
|
|
is_forwarded,
|
|
is_cut,
|
|
top_quote,
|
|
footer,
|
|
} = dehtml;
|
|
assert_eq!(text, "Test");
|
|
assert_eq!(is_forwarded, false);
|
|
assert_eq!(is_cut, false);
|
|
assert_eq!(top_quote.as_deref(), Some("test"));
|
|
assert_eq!(footer, None);
|
|
}
|
|
|
|
#[test]
|
|
fn test_spaces() {
|
|
let input = include_str!("../test-data/spaces.html");
|
|
let txt = dehtml(input).unwrap();
|
|
assert_eq!(txt.text, "Welcome back to Strolling!\n\nHey there,\n\nWelcome back! Use this link to securely sign in to your Strolling account:\n\nSign in to Strolling\n\nFor your security, the link will expire in 24 hours time.\n\nSee you soon!\n\nYou can also copy & paste this URL into your browser:\n\nhttps://strolling.rosano.ca/members/?token=XXX&action=signin&r=https%3A%2F%2Fstrolling.rosano.ca%2F\n\nIf you did not make this request, you can safely ignore this email.\n\nThis message was sent from [strolling.rosano.ca](https://strolling.rosano.ca/) to [alice@example.org](mailto:alice@example.org)");
|
|
}
|
|
}
|