2022-03-25 18:07:04 +01:00

248 lines
9.7 KiB
Rust

//! Types for extensible text message events ([MSC1767]).
//!
//! # Extensible events
//!
//! MSCs [1767] (Text, Emote and Notice), [3551] (Files), [3552] (Images and Stickers), [3553]
//! (Videos), [3246] (Audio), and [3488] (Location) introduce new primary types called extensible
//! events. These types are meant to replace the `m.room.message` primary type and its `msgtype`s.
//! Other MSCs introduce new types with an `m.room.message` fallback, like [MSC3245] (Voice
//! Messages), and types that only have an extensible events format, like [MSC3381] (Polls).
//!
//! # Transition Period
//!
//! MSC1767 defines a transition period that will start after the extensible events are released in
//! a Matrix version. It should last approximately one year, but the end of that period will be
//! formalized in a new Matrix version.
//!
//! The new primary types should not be sent over the Matrix network before the end of the
//! transition period. Instead, transitional `m.room.message` events should be sent. These
//! transitional events include the content of the now legacy `m.room.message` event and the content
//! of the new extensible event types in a single event.
//!
//! # How to use them
//!
//! First, enable the `unstable-mscXXXX` features (where `XXXX` is the number of the MSC) for the
//! needed extensible types.
//!
//! The recommended way to send transitional extensible events while they are unstable and during
//! the transition period is to build one of the new primary types and then to convert it to a
//! [`RoomMessageEventContent`] by using `.into()` or `RoomMessageEventContent::from()`. The
//! provided constructors will copy the relevant data in the legacy fields.
//!
//! For incoming events, a `RoomMessageEventContent` can be converted to an extensible event with
//! the relevant `from_*_room_message` method on the primary type. This conversion will work even
//! with legacy `m.room.message` events that don't have extensible events content.
//!
//! It is also possible to enable extensible events support and continue using
//! `RoomMessageEventContent`'s constructors. The data will be duplicated in both the legacy and
//! extensible events fields.
//!
//! [MSC1767]: https://github.com/matrix-org/matrix-spec-proposals/pull/1767
//! [1767]: https://github.com/matrix-org/matrix-spec-proposals/pull/1767
//! [3551]: https://github.com/matrix-org/matrix-spec-proposals/pull/3551
//! [3552]: https://github.com/matrix-org/matrix-spec-proposals/pull/3552
//! [3553]: https://github.com/matrix-org/matrix-spec-proposals/pull/3553
//! [3246]: https://github.com/matrix-org/matrix-spec-proposals/pull/3246
//! [3488]: https://github.com/matrix-org/matrix-spec-proposals/pull/3488
//! [MSC3245]: https://github.com/matrix-org/matrix-spec-proposals/pull/3245
//! [MSC3381]: https://github.com/matrix-org/matrix-spec-proposals/pull/3381
//! [`RoomMessageEventContent`]: super::room::message::RoomMessageEventContent
use ruma_macros::EventContent;
use serde::{Deserialize, Serialize};
mod content_serde;
use content_serde::MessageContentSerDeHelper;
use super::room::message::{FormattedBody, MessageFormat, Relation, TextMessageEventContent};
/// The payload for an extensible text message.
///
/// This is the new primary type introduced in [MSC1767] and should not be sent before the end of
/// the transition period. See the documentation of the [`message`] module for more information.
///
/// `MessageEventContent` can be converted to a [`RoomMessageEventContent`] with a
/// [`MessageType::Text`]. You can convert it back with
/// [`MessageEventContent::from_text_room_message()`].
///
/// [MSC1767]: https://github.com/matrix-org/matrix-spec-proposals/pull/1767
/// [`message`]: super::message
/// [`RoomMessageEventContent`]: super::room::message::RoomMessageEventContent
/// [`MessageType::Text`]: super::room::message::MessageType::Text
#[derive(Clone, Debug, Serialize, Deserialize, EventContent)]
#[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
#[ruma_event(type = "m.message", kind = MessageLike)]
pub struct MessageEventContent {
/// The message's text content.
#[serde(flatten)]
pub message: MessageContent,
/// Information about related messages for [rich replies].
///
/// [rich replies]: https://spec.matrix.org/v1.2/client-server-api/#rich-replies
#[serde(flatten, skip_serializing_if = "Option::is_none")]
pub relates_to: Option<Relation>,
}
impl MessageEventContent {
/// A convenience constructor to create a plain text message.
pub fn plain(body: impl Into<String>) -> Self {
Self { message: MessageContent::plain(body), relates_to: None }
}
/// A convenience constructor to create an HTML message.
pub fn html(body: impl Into<String>, html_body: impl Into<String>) -> Self {
Self { message: MessageContent::html(body, html_body), relates_to: None }
}
/// A convenience constructor to create a Markdown message.
///
/// Returns an HTML message if some Markdown formatting was detected, otherwise returns a plain
/// text message.
#[cfg(feature = "markdown")]
pub fn markdown(body: impl AsRef<str> + Into<String>) -> Self {
Self { message: MessageContent::markdown(body), relates_to: None }
}
/// Create a new `MessageEventContent` from the given `TextMessageEventContent` and optional
/// relation.
pub fn from_text_room_message(
content: TextMessageEventContent,
relates_to: Option<Relation>,
) -> Self {
let TextMessageEventContent { body, formatted, message, .. } = content;
if let Some(message) = message {
Self { message, relates_to }
} else {
Self { message: MessageContent::from_room_message_content(body, formatted), relates_to }
}
}
}
/// Text message content.
#[derive(Clone, Debug, Deserialize)]
#[serde(try_from = "MessageContentSerDeHelper")]
pub struct MessageContent(pub(crate) Vec<Text>);
impl MessageContent {
/// A convenience constructor to create a plain text message.
pub fn plain(body: impl Into<String>) -> Self {
Self(vec![Text::plain(body)])
}
/// A convenience constructor to create an HTML message.
pub fn html(body: impl Into<String>, html_body: impl Into<String>) -> Self {
Self(vec![Text::html(html_body), Text::plain(body)])
}
/// A convenience constructor to create a Markdown message.
///
/// Returns an HTML message if some Markdown formatting was detected, otherwise returns a plain
/// text message.
#[cfg(feature = "markdown")]
pub fn markdown(body: impl AsRef<str> + Into<String>) -> Self {
let mut message = Vec::with_capacity(2);
if let Some(html_body) = Text::markdown(&body) {
message.push(html_body);
}
message.push(Text::plain(body));
Self(message)
}
/// Create a new `MessageContent` from the given body and optional formatted body.
pub fn from_room_message_content(body: String, formatted: Option<FormattedBody>) -> Self {
if let Some(FormattedBody { body: html_body, .. }) =
formatted.filter(|formatted| formatted.format == MessageFormat::Html)
{
Self::html(body, html_body)
} else {
Self::plain(body)
}
}
/// Get the plain text representation of this message.
pub fn find_plain(&self) -> Option<&str> {
self.variants()
.iter()
.find(|content| content.mimetype == "text/plain")
.map(|content| content.body.as_ref())
}
/// Get the HTML representation of this message.
pub fn find_html(&self) -> Option<&str> {
self.variants()
.iter()
.find(|content| content.mimetype == "text/html")
.map(|content| content.body.as_ref())
}
/// Get all the text representations of this message.
pub fn variants(&self) -> &[Text] {
&self.0
}
}
impl From<Vec<Text>> for MessageContent {
fn from(variants: Vec<Text>) -> Self {
Self(variants)
}
}
/// Text message content.
#[derive(Clone, Debug, Serialize, Deserialize)]
#[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
pub struct Text {
/// The mime type of the `body`.
#[serde(default = "Text::default_mimetype")]
pub mimetype: String,
/// The text content.
pub body: String,
/// The language of the text.
///
/// This must be a valid language code according to [BCP 47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
#[cfg(feature = "unstable-msc3554")]
#[serde(skip_serializing_if = "Option::is_none")]
pub lang: Option<String>,
}
impl Text {
/// Creates a new plain text message body.
pub fn plain(body: impl Into<String>) -> Self {
Self {
mimetype: "text/plain".to_owned(),
body: body.into(),
#[cfg(feature = "unstable-msc3554")]
lang: None,
}
}
/// Creates a new HTML-formatted message body.
pub fn html(body: impl Into<String>) -> Self {
Self {
mimetype: "text/html".to_owned(),
body: body.into(),
#[cfg(feature = "unstable-msc3554")]
lang: None,
}
}
/// Creates a new HTML-formatted message body by parsing the Markdown in `body`.
///
/// Returns `None` if no Markdown formatting was found.
#[cfg(feature = "markdown")]
pub fn markdown(body: impl AsRef<str>) -> Option<Self> {
let body = body.as_ref();
let mut html_body = String::new();
pulldown_cmark::html::push_html(&mut html_body, pulldown_cmark::Parser::new(body));
(html_body != format!("<p>{}</p>\n", body)).then(|| Self::html(html_body))
}
fn default_mimetype() -> String {
"text/plain".to_owned()
}
}