files.upload Web API method sunset on 2025-11-12

Provider

Slack

Endpoint

POST /api/files.upload

Effective

2025-11-12

Severity

critical

Change

version-sunset

Status

verified

What changed

Slack deprecated files.upload. Apps created on or after 2024-05-16 could not use it, and Slack's reference page says the method stops working and is sunset on 2025-11-12 for existing apps too (the date was moved from 2025-03-11). Code that still uploads through files.upload fails with method_deprecated or deprecated_endpoint errors.

What to do

Replace files.upload with the two-step flow: call files.getUploadURLExternal (filename, length) to get an upload_url and file_id, POST the file bytes to upload_url, then call files.completeUploadExternal with the file_id(s) and the channel_id, initial_comment or thread_ts you used to pass to files.upload. The official Slack SDKs wrap this as files_upload_v2 / filesUploadV2 / uploadV2.

Sources

• Provider notice (2025-03-17)
• https://docs.slack.dev/reference/methods/files.upload
• https://docs.slack.dev/changelog/2024-04-a-better-way-to-upload-files-is-here-to-stay

Check your code

npx shapi-cli scan .

shapi scan lists the call sites this change affects; shapi fix repairs them test-first when the advisory has an automatic fix. All advisories · Markdown · OSV · JSON