hcengineering/platform · error · Error

Unknown content format

Error message

Unknown content format

What it means

fetchMarkup converts stored collaborative markup into a requested format ('markup', 'html', or 'markdown'). If the format argument matches none of these cases, the switch falls through to default and throws 'Unknown content format'. This indicates an invalid or unsupported MarkupFormat value at runtime.

Source

Thrown at foundations/core/packages/api-client/src/markup/client.ts:76

    objectClass: Ref<Class<Doc>>,
    objectId: Ref<Doc>,
    objectAttr: string,
    doc: MarkupRef,
    format: MarkupFormat
  ): Promise<string> {
    const collabId = makeCollabId(objectClass, objectId, objectAttr)
    const markup = await this.collaborator.getMarkup(collabId, doc)
    const json = markupToJSON(markup)

    switch (format) {
      case 'markup':
        return markup
      case 'html':
        return jsonToHTML(json)
      case 'markdown':
        return markupToMarkdown(json, { refUrl: this.refUrl, imageUrl: this.imageUrl })
      default:
        throw new Error('Unknown content format')
    }
  }

  async uploadMarkup (
    objectClass: Ref<Class<Doc>>,
    objectId: Ref<Doc>,
    objectAttr: string,
    value: string,
    format: MarkupFormat
  ): Promise<MarkupRef> {
    let markup: Markup = ''

    switch (format) {
      case 'markup':
        markup = value
        break
      case 'html':
        markup = jsonToMarkup(htmlToJSON(value))

View on GitHub (pinned to 63e28dc964)

Solutions

1. Pass exactly one of 'markup', 'html', or 'markdown' as the format argument.
2. Validate/normalize the format string (lowercase, map aliases like 'md' -> 'markdown') before calling fetchMarkup.
3. Use the MarkupFormat type and avoid unchecked casts so TypeScript rejects invalid values.

Example fix

// before
client.fetchMarkup(cls, id, 'content', doc, 'md' as MarkupFormat)
// after
const fmt = format === 'md' ? 'markdown' : format
if (!['markup', 'html', 'markdown'].includes(fmt)) throw new Error('unsupported format: ' + format)
client.fetchMarkup(cls, id, 'content', doc, fmt as MarkupFormat)

const FORMATS = ['markup', 'html', 'markdown'] as const
if (!FORMATS.includes(format as any)) throw new Error(`Invalid markup format: ${format}; expected one of ${FORMATS.join(', ')}`)

function isMarkupFormat(v: unknown): v is 'markup' | 'html' | 'markdown' {
  return v === 'markup' || v === 'html' || v === 'markdown'
}

try {
  return await client.fetchMarkup(cls, id, attr, doc, format)
} catch (e) {
  if (e instanceof Error && e.message === 'Unknown content format') {
    throw new Error(`Unsupported export format "${String(format)}" — use 'markup', 'html' or 'markdown'`)
  }
  throw e
}

When it happens

Trigger: Calling fetchMarkup(objectClass, objectId, attr, doc, format) with format that is not exactly 'markup' | 'html' | 'markdown' — e.g. 'md', 'text', 'richtext', or a value cast incorrectly to MarkupFormat.

Common situations: Hand-building a format string instead of using the MarkupFormat type, user-configurable export format from a UI/config reaching the API unvalidated, TypeScript types bypassed with `as MarkupFormat`.

Understand the failure class

Background: Invalid enum value errors: "Unknown type", "Invalid scope", "must be one of" — when a string is not on the library's allowed list — this error's family across 23 libraries.

Related errors

• Message id is required
• Failed to load server config
• getDisplayMedia not supported
• No screen access granted
• Message id is required

AI-assisted analysis of hcengineering/platform@63e28dc964 (2026-08-29). Data as JSON: /api/errors/e9fb2a3f056f9cf2. Report an issue: GitHub.