Filter Draft.js content to preserve only the formatting you allow. Built for Draftail.
The main use case is to select what formatting to keep when copy-pasting rich text into an editor, for example from Word or Google Docs, addressing Draft.js limitations like #166 and #504. Check out the online demo!
If you want to learn more about how this is used in practice, have a look at Rethinking rich text pipelines with Draft.js.
Using the filters
First, grab the package from npm:
npm install --save draftjs-filters
Then, in your editor import filterEditorState
and call it in the Draft.js onChange
handler. This function takes two parameters: the filtering configuration, and the editorState
.
import { filterEditorState } from "draftjs-filters"
function onChange(nextState) {
const { editorState } = this.state
let filteredState = nextState
const shouldFilterPaste =
nextState.getCurrentContent() !== editorState.getCurrentContent() &&
nextState.getLastChangeType() === "insert-fragment"
if (shouldFilterPaste) {
filteredState = filterEditorState(
{
blocks: ["header-two", "header-three", "unordered-list-item"],
styles: ["BOLD"],
entities: [
{
type: "IMAGE",
attributes: ["src"],
allowlist: {
src: "^http",
},
},
{
type: "LINK",
attributes: ["url"],
},
],
maxNesting: 1,
whitespacedCharacters: ["\n", "\t", "📷"],
},
filteredState,
)
}
this.setState({ editorState: filteredState })
}
Here are all the available options:
blocks: readonly string[]>,
styles: readonly string[]>,
entities: readonly []<{
type: string,
attributes?: readonly string[]>,
allowlist?: {
[attribute: string]: string | boolean,
},
}>,
maxNesting: number,
whitespacedCharacters: Array<string>,
blockTextRules?: readonly []<{
test: string,
type: string,
depth: number,
}>,
Deprecated
filterEditorState
(and shouldKeepEntityByAttribute
described further below) used to support a whitelist
config option. It has been renamed to allowlist
, and will be removed altogether in a future release.
Types
If your project uses TypeScript, type inference should just work. If you don't use TypeScript, it won't get in your way either.
Flow types were included up to v2.5.0 of the package, and have been removed in v3.0.0.
Advanced usage
filterEditorState
isn't very flexible. If you want more control over the filtering, simply compose your own filter function with the other single-purpose utilities. The Draft.js filters are published as ES6 modules using Rollup – module bundlers like Rollup and Webpack will tree shake (remove) the unused functions so you only bundle the code you use.
If using filters that remove blocks, be sure to use applyContentWithSelection
to restore the selection where appropriate after filtering.
API
preserveAtomicBlocks
Creates atomic blocks where they would be required for a block-level entity
to work correctly, when such an entity exists.
Note: at the moment, this is only useful for IMAGE entities that Draft.js
injects on arbitrary blocks on paste.
Parameters
resetAtomicBlocks
Resets atomic blocks to have a single-space char and no styles.
This is how they are stored by Draft.js by default.
Parameters
removeInvalidAtomicBlocks
Removes atomic blocks for which the entity type isn't allowed.
Parameters
allowlist
readonly {type: string}[]content
ContentState
removeInvalidDepthBlocks
Removes blocks that have a non-zero depth, and aren't list items.
Happens with Apple Pages inserting unstyled
items between list items.
Parameters
preserveBlockByText
Changes block type and depth based on the block's text. – some word processors
add a specific prefix within the text, eg. "· Bulleted list" in Word 2010.
Also removes the matched text.
This is meant first and foremost for list items where the list bullet or numeral
ends up in the text. Other use cases may not be well covered.
Parameters
limitBlockDepth
Resets the depth of all the content to at most max.
Parameters
max
numbercontent
ContentState
filterBlockTypes
Converts all block types not present in the list to unstyled.
Also sets depth to 0 (for potentially nested list items).
Parameters
allowlist
readonly string[]content
ContentState
filterInlineStyles
Removes all styles not present in the list.
Parameters
allowlist
readonly string[]content
ContentState
cloneEntities
Clones entities in the entityMap, so each range points to its own entity instance.
This only clones entities as necessary – if an entity is only referenced
in a single range, it won't be changed.
Parameters
filterEntityRanges
Filters entity ranges (where entities are applied on text) based on the result of
the callback function. Returning true keeps the entity range, false removes it.
Draft.js automatically removes entities if they are not applied on any text.
Parameters
filterFn
function (content: ContentState, entityKey: string, block: BlockNode): booleancontent
ContentState
shouldKeepEntityType
Keeps all entity types (images, links, documents, embeds) that are enabled.
Parameters
shouldRemoveImageEntity
Removes invalid images – they should only be in atomic blocks.
This only removes the image entity, not the camera emoji (📷) that Draft.js inserts.
Parameters
shouldKeepEntityByAttribute
Filters entities based on the data they contain.
Parameters
entityTypes
readonly {type: string, allowlist: {}?, whitelist: {}?}[]entityType
stringdata
{ [attr: string]: any }
filterEntityData
Filters data on an entity to only retain what is allowed.
This is crucial for IMAGE and LINK, where Draft.js adds a lot
of unneeded attributes (width, height, etc).
Parameters
entityTypes
readonly {type: string, attributes: readonly string>?}[]content
ContentState
replaceTextBySpaces
Replaces the given characters by their equivalent length of spaces, in all blocks.
Parameters
characters
readonly string[]content
ContentState
applyContentWithSelection
Applies the new content to the editor state, optionally moving the selection
to be on a valid block, inserting one if needed.
See https://github.com/thibaudcolas/draftjs-filters/issues/27.
Parameters
editorState
EditorStatecontent
ContentStatenextContent
ContentState
filterEditorState
Applies filtering and preservation operations to the editor content,
to restrict it to supported patterns.
Will not alter the editor state if there are no changes to make.
Parameters
options
FilterOptionseditorState
EditorState
condenseBlocks
Condenses an array of content blocks into a single block.
- Skipping the undo-redo stack.
- Adding a space between each block to match the behavior of vanilla HTML fields.
- Making sure the space gets the correct styles or entities applied.
- Placing the selection at the same end offset as the last selection.
This exhibits two known issues:
- A link / other entity spread over multiple lines will be split into multiple entities of identical data.
- Upon redo-ing the change, the selection isn’t correctly placed.
Parameters
nextState
EditorStateprevState
EditorState
Browser support and polyfills
The Draft.js filters only support modern browsers with ES2020 features. Support for legacy browsers can be achieved, up to IE11, by appropriately transpiling the package’s code and including the required Draft.js polyfills.
Word processor support
Have a look at our test data in pasting/
.
Editor - Browser | Chrome Windows | Chrome macOS | Firefox Windows | Firefox macOS | Edge Windows | IE11 Windows | Safari macOS | Safari iOS | Chrome Android |
---|
Word 2016 | | | | | | | | N/A | N/A |
Word 2010 | | N/A | | N/A | | | N/A | N/A | N/A |
Apple Pages | N/A | | N/A | | N/A | N/A | | | N/A |
Google Docs | | | | | | | | | |
Word Online | | | | | | Unsupported | | ? | ? |
Dropbox Paper | | | | | | Unsupported | | ? | ? |
Draft.js | | | | | | | | | |
Use the Draft.js Cut/Copy/Paste testing plan. We target specific external sources, and have ready-made test documents available to test them:
External sources
Here are external sources we want to pay special attention to, and for which we have ready-made test documents with diverse rich content.
IE11
There are known Draft.js issues with pasting in IE11. For now, we advise users to turn on stripPastedStyles
in IE11 only so that Draft.js removes all formatting but preserves whitespace:
const IS_IE11 = !window.ActiveXObject && "ActiveXObject" in window
const editor = <Editor stripPastedStyles={IS_IE11} />
Contributing
See anything you like in here? Anything missing? We welcome all support, whether on bug reports, feature requests, code, design, reviews, tests, documentation, and more. Please have a look at our contribution guidelines.
Credits
View the full list of contributors. MIT licensed. Website content available as CC0.
Microsoft Word toolbars screenshot from PCWorld – Microsoft Word Turns 25 article.