mirror of
https://github.com/element-hq/element-web
synced 2024-11-24 02:05:45 +03:00
88 lines
No EOL
5 KiB
Markdown
88 lines
No EOL
5 KiB
Markdown
Guide to data types used by the Slate-based Rich Text Editor
|
|
------------------------------------------------------------
|
|
|
|
We always store the Slate editor state in its Value form.
|
|
|
|
The schema for the Value is the same whether the editor is in MD or rich text mode, and is currently (rather arbitrarily)
|
|
dictated by the schema expected by slate-md-serializer, simply because it was the only bit of the pipeline which
|
|
has opinions on the schema. (slate-html-serializer lets you define how to serialize whatever schema you like).
|
|
|
|
The BLOCK_TAGS and MARK_TAGS give the mapping from HTML tags to the schema's node types (for blocks, which describe
|
|
block content like divs, and marks, which describe inline formatted sections like spans).
|
|
|
|
We use <p/> as the parent tag for the message (XXX: although some tags are technically not allowed to be nested within p's)
|
|
|
|
Various conversions are performed as content is moved between HTML, MD, and plaintext representations of HTML and MD.
|
|
|
|
The primitives used are:
|
|
|
|
* Markdown.js - models commonmark-formatted MD strings (as entered by the composer in MD mode)
|
|
* toHtml() - renders them to HTML suitable for sending on the wire
|
|
* isPlainText() - checks whether the parsed MD contains anything other than simple text.
|
|
* toPlainText() - renders MD to plain text in order to remove backslashes. Only works if the MD is already plaintext (otherwise it just emits HTML)
|
|
|
|
* slate-html-serializer
|
|
* converts Values to HTML (serialising) using our schema rules
|
|
* converts HTML to Values (deserialising) using our schema rules
|
|
|
|
* slate-md-serializer
|
|
* converts rich Values to MD strings (serialising) but using a non-commonmark generic MD dialect.
|
|
* This should use commonmark, but we use the serializer here for expedience rather than writing a commonmark one.
|
|
|
|
* slate-plain-serializer
|
|
* converts Values to plain text strings (serialising them) by concatenating the strings together
|
|
* converts Values from plain text strings (deserialiasing them).
|
|
* Used to initialise the editor by deserializing "" into a Value. Apparently this is the idiomatic way to initialise a blank editor.
|
|
* Used (as a bodge) to turn a rich text editor into a MD editor, when deserialising the converted MD string of the editor into a value
|
|
|
|
* PlainWithPillsSerializer
|
|
* A fork of slate-plain-serializer which is aware of Pills (hence the name) and Emoji.
|
|
* It can be configured to output Pills as:
|
|
* "plain": Pills are rendered via their 'completion' text - e.g. 'Matthew'; used for sending messages)
|
|
* "md": Pills are rendered as MD, e.g. [Matthew](https://matrix.to/#/@matthew:matrix.org) )
|
|
* "id": Pills are rendered as IDs, e.g. '@matthew:matrix.org' (used for authoring / commands)
|
|
* Emoji nodes are converted to inline utf8 emoji.
|
|
|
|
The actual conversion transitions are:
|
|
|
|
* Quoting:
|
|
* The message being quoted is taken as HTML
|
|
* ...and deserialised into a Value
|
|
* ...and then serialised into MD via slate-md-serializer if the editor is in MD mode
|
|
|
|
* Roundtripping between MD and rich text editor mode
|
|
* From MD to richtext (mdToRichEditorState):
|
|
* Serialise the MD-format Value to a MD string (converting pills to MD) with PlainWithPillsSerializer in 'md' mode
|
|
* Convert that MD string to HTML via Markdown.js
|
|
* Deserialise that Value to HTML via slate-html-serializer
|
|
* From richtext to MD (richToMdEditorState):
|
|
* Serialise the richtext-format Value to a MD string with slate-md-serializer (XXX: this should use commonmark)
|
|
* Deserialise that to a plain text value via slate-plain-serializer
|
|
|
|
* Loading history in one format into an editor which is in the other format
|
|
* Uses the same functions as for roundtripping
|
|
|
|
* Scanning the editor for a slash command
|
|
* If the editor is a single line node starting with /, then serialize it to a string with PlainWithPillsSerializer in 'id' mode
|
|
So that pills get converted to IDs suitable for commands being passed around
|
|
|
|
* Sending messages
|
|
* In RT mode:
|
|
* If there is rich content, serialize the RT-format Value to HTML body via slate-html-serializer
|
|
* Serialize the RT-format Value to the plain text fallback via PlainWithPillsSerializer in 'plain' mode
|
|
* In MD mode:
|
|
* Serialize the MD-format Value into an MD string with PlainWithPillsSerializer in 'md' mode
|
|
* Parse the string with Markdown.js
|
|
* If it contains no formatting:
|
|
* Send as plaintext (as taken from Markdown.toPlainText())
|
|
* Otherwise
|
|
* Send as HTML (as taken from Markdown.toHtml())
|
|
* Serialize the RT-format Value to the plain text fallback via PlainWithPillsSerializer in 'plain' mode
|
|
|
|
* Pasting HTML
|
|
* Deserialize HTML to a RT Value via slate-html-serializer
|
|
* In RT mode, insert it straight into the editor as a fragment
|
|
* In MD mode, serialise it to an MD string via slate-md-serializer and then insert the string into the editor as a fragment.
|
|
|
|
The various scenarios and transitions could be drawn into a pretty diagram if one felt the urge, but hopefully the above
|
|
gives sufficient detail on how it's all meant to work. |