transloadit/uppy · info · Error

Companion request failed: ${response.statusText}

Error message

Companion request failed: ${response.statusText}

What it means

The logout controller cleans the session and returns 400 when no provider instance is available — meaning Companion cannot perform a server-side token revocation for that provider, though it still clears the local session first (cleanSession()).

Source

Thrown at packages/@uppy/aws-s3/src/s3-client/CompanionS3.ts:23

/**
 * S3Companion is an S3Client that interacts with a Companion server to perform S3 operations.
 */
class S3Companion extends S3Client {
  readonly companionEndpoint: string

  constructor({
    companionEndpoint,
    requestAbortTimeout,
  }: { companionEndpoint: string; requestAbortTimeout?: number | undefined }) {
    super({ requestAbortTimeout })
    this.companionEndpoint = companionEndpoint
  }

  private async _fetch(path: string, opts?: RequestInit) {
    const response = await fetch(`${this.companionEndpoint}/s3${path}`, opts)
    if (!response.ok) {
      throw new Error(`Companion request failed: ${response.statusText}`)
    }
    return response
  }

  private async _request({
    url,
    method,
    data,
    onProgress,
    signal,
    contentType,
  }: {
    url: string
    method: IT.HttpMethod
    data?: XMLHttpRequestBodyInit
    onProgress?: IT.OnProgressFn
    signal?: AbortSignal
    contentType?: string

View on GitHub (pinned to 5d4dedd02a)

Solutions

1. Align the providers configured on Companion with what the client uses
2. Ensure the request carries a valid provider session token
3. If the goal is only local cleanup, treat 400 as acceptable — the session was still cleaned server-side

Example fix

// before
const res = await fetch('/companion/box/logout', { method: 'POST' })
if (!res.ok) throw new Error('logout failed')
// after
const res = await fetch('/companion/box/logout', { method: 'POST' })
// 400 still means the local session was cleaned; provider revocation was skipped

const res = await fetch(`${companionUrl}/${provider}/logout`, { method: 'POST' })
// 400 still means local session was cleaned; treat as success for local logout

try {
  await logout()
} catch {
  // best-effort: clear local state regardless of server response
  clearLocalSession()
}

When it happens

Trigger: Calling /logout for a provider that is not configured on this Companion instance, or when the provider session middleware failed to instantiate the provider (bad/expired token).

Common situations: Frontend and backend provider lists out of sync; logging out after the provider config was removed; token already expired so provider was not attached.

Related errors

• Missing S3 object key for aborting upload
• Missing S3 object key for resuming upload
• Missing S3 object key for uploading part
• companionEndpoint must be a string
• s3Endpoint must be a string

AI-assisted analysis of transloadit/uppy@5d4dedd02a (2026-08-28). Data as JSON: /api/errors/0726173f8f231432. Report an issue: GitHub.