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Html API

HTML utility methods and event inspection helpers.

Overview

This module provides 13 methods.

Methods

buildMentionHtml()

Signature: buildMentionHtml(text, getDisplayName)

Replaces @user:server patterns in plain text with HTML anchor mention links.

Parameters:

  • text {string} - Plain text possibly containing Matrix user IDs.
  • getDisplayName {function(string): string} - Callback to resolve a user ID to a display name.

Returns: string|null - HTML string with mentions linked, or null if no mentions were found.

extractLocalpart()

Signature: extractLocalpart(userId)

Extracts the localpart from a Matrix user ID (the segment before the colon).

Parameters:

  • userId {string} - A Matrix user ID (e.g. @alice:example.com).

Returns: string - The localpart, or "?" if extraction fails.

formatMarkdownToHtml()

Signature: formatMarkdownToHtml(markdown)

Converts Markdown text to HTML. This is a basic implementation supporting common markdown syntax.

Parameters:

  • markdown {string} - Markdown text to convert

Returns: string - HTML-formatted string

getEditedBody()

Signature: getEditedBody(event)

Extracts the text body from an edited message event. Falls back to the regular body if no m.new_content is present.

Parameters:

  • event {Object} - A Matrix room event.

Returns: string|null

getEventRelation()

Signature: getEventRelation(event)

Returns the m.relates_to relation object from an event, if present.

Parameters:

  • event {Object} - A Matrix room event.

Returns: Object|null

getMembershipChange()

Signature: getMembershipChange(event)

Interprets an m.room.member event and returns a structured description of the membership change.

Parameters:

  • event {Object} - A Matrix m.room.member state event.

Returns: {type: "join"|"rename"|"avatar"|"leave"|"kick"|"ban"|"unknown", userId: string, displayName: string|null, prevDisplayName: string|null, avatarUrl: string|null, prevAvatarUrl?: string|null, kicker: string|null - |null}

getPrevContent()

Signature: getPrevContent(event)

Returns the previous content (unsigned.prev_content) of a state event, if present.

Parameters:

  • event {Object} - A Matrix room event.

Returns: Object|null

hasFormattedBody()

Signature: hasFormattedBody(event)

Checks whether a message event contains an HTML-formatted body.

Parameters:

  • event {Object} - A Matrix room event.

Returns: boolean

Example:

if (client.hasFormattedBody(event)) {
  // It's a formatted body
}

isEditEvent()

Signature: isEditEvent(event)

Checks whether an event is a message edit (m.replace relation).

Parameters:

  • event {Object} - A Matrix room event.

Returns: boolean

Example:

if (client.isEditEvent(event)) {
  // It's an edit event
}

isImageMessage()

Signature: isImageMessage(event)

Checks whether an event is an image message.

Parameters:

  • event {Object} - A Matrix room event.

Returns: boolean

Example:

if (client.isImageMessage(event)) {
  // It's an image message
}

isMention()

Signature: isMention(event, userId)

HTML utility methods and event inspection helpers.

Parameters:

  • Base {T}
  • event {Object} - A Matrix room event.
  • userId {string} - The user ID to check for.

Returns: boolean

Example:

if (client.isMention(Base, event, '@user:matrix.org')) {
  // It's a mention
}

isReactionEvent()

Signature: isReactionEvent(event)

Checks whether an event is a reaction annotation (m.annotation).

Parameters:

  • event {Object} - A Matrix room event.

Returns: boolean

Example:

if (client.isReactionEvent(event)) {
  // It's a reaction event
}

sanitizeHtml()

Signature: sanitizeHtml(html)

Sanitizes an HTML string, permitting only a safe subset of tags and converting Matrix mention links into <span class="mention"> elements.

Parameters:

  • html {string} - Raw HTML string to sanitize.

Returns: string - The sanitized HTML string.

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