Migrate MinIO bucket: Generated downloads

Summary

Move object storage from MinIO bucket to Ample, one component at a time. Destination verified on Ample: an export query rendered to a CSV artifact stored with metadata in a private bucket and returned only to an authorized caller (401 without token, export=ok rows=3). Source procedure: Inventory the bucket with mc du or rclone size. Not migrated automatically: MinIO bucket policies, versioning, replication, ILM rules and notifications are not migrated. Cutover: Switch the app's S3_* environment to the Ample bucket with a redeploy, verify reads and writes, keep MinIO read-only until confirmed. Rollback: keep the source untouched until you confirm; nothing at the source is changed or deleted by this guide.

Infrastructure requirements

• S3-compatible object storage: verified (Buckets are S3-compatible with issued credentials; PutObject and GetObject are verified by canary. Other S3 operations are not verified.)

Prerequisites

• Authorized access to the MinIO bucket source and its export tooling
• An inventory of every component in scope and out of scope
• A validated backup or copy before any cutover
• An Ample account token with servers:write, buckets:write

Exact tested configuration

• template: node-22
• runtime: node
• size: s-1vcpu-1gb
• install: npm install
• build: npm run build --if-present
• start: npm run start

Steps

1. Inventory the source. List what MinIO bucket provides beyond the component you are moving. Out of scope here: MinIO bucket policies, versioning, replication, ILM rules and notifications are not migrated.
2. Source step 1. Inventory the bucket with mc du or rclone size
3. Source step 2. Copy objects with mc mirror or rclone sync from MinIO to the Ample bucket endpoint using the issued credentials (path-style)
4. Source step 3. Verify a sample of objects by size and checksum after the copy
5. Create the destination bucket and copy. Create the bucket, copy with rclone or the S3 CLI in path-style mode using the issued credentials, then pass the credentials to the app as encrypted S3_* variables.

   ample bucket create --name <bucket-name>

6. Validate before cutover. Run the app's own checks and, for data, compare counts and checksums; the example checks are the pattern self-tests (/p/generated-downloads).
7. Cut over. Switch the app's S3_* environment to the Ample bucket with a redeploy, verify reads and writes, keep MinIO read-only until confirmed.
8. Rollback. Point DNS or configuration back to the source. The source was never modified; deletion is a separate, user-executed step after validation.

Tested examples

• Express pattern fixture (destination) (tests/deploy-canaries/express-patterns): Verified destination basis: generated downloads.

Success checks

• destination app responds on its public URL (/ on the live URL, expect ample canary express patterns)
• generated-downloads check from the destination example (/p/generated-downloads on the live URL, expect see the pattern fixture checks)
• data or object counts and checksums match the source

Limitations

• Documentation only: nothing is executed automatically and no execution binding is offered.
• The source-side procedure is documented from MinIO bucket's standard tooling and was not executed in this catalog's evidence; the destination side was verified with the pattern fixture.
• No full source-product parity is claimed: MinIO bucket policies, versioning, replication, ILM rules and notifications are not migrated.
• Verified on the node-22 template at s-1vcpu-1gb; region, compliance and request-duration limits are unknown.
• PutObject and GetObject with path-style addressing are verified; bulk copy tooling and other S3 operations are not.