Uploading large files into Multi FileFeeds

Step 1 — Create a Multi FileFeed Import

Create a new import on the target Multi FileFeed. This returns an import object whose id you will use in all subsequent calls.

POST /v0/workflows/{multi_file_feed_id}/imports

curl -X POST "https://api.oneschema.co/v0/workflows/42/imports" \
  -H "X-API-KEY: YOUR_API_KEY"

Response

{
  "id": 101,
  "multi_file_feed_id": 42,
  "status": "initialized",
  "created_at": "2026-03-02T12:00:00Z"
}

Save the returned id — this is your multi_file_feed_import_id used in all following steps.

API reference: Create a Multi FileFeed import

Step 2 — Upload Files

Repeat steps 2a–2c for every file you need to add to the import.

Step 2a — Create a Direct Upload

Request a presigned URL for the file you want to upload. Pass the filename in the request body — it must be unique within the import.

POST /v0/workflows/{multi_file_feed_id}/imports/{multi_file_feed_import_id}/direct-uploads

curl -X POST "https://api.oneschema.co/v0/workflows/42/imports/101/direct-uploads" \
  -H "X-API-KEY: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"filename": "orders.csv"}'

Response

{
  "upload_id": 555,
  "presigned_url": "https://storage.example.com/bucket/path?signature=abc123",
  "content_type": "text/csv"
}

Hold on to all three values — you need them in the next steps.

API reference: Create a direct file upload for a Multi FileFeed import

Step 2b — Upload the File to the Presigned URL

Upload the file directly to cloud storage using the presigned_url from Step 2a. You must set the Content-Type header to the exact content_type value returned in Step 2a — the file store will reject the upload otherwise.

curl -X PUT "https://storage.example.com/bucket/path?signature=abc123" \
  -H "Content-Type: text/csv" \
  --data-binary @orders.csv

The presigned URL expires after 1 hour. Complete the upload before it expires.

Step 2c — Submit the Direct Upload

After the file has been successfully uploaded, call the submit endpoint to finalize it. OneSchema verifies the upload and links the file to the import.

POST /v0/workflows/{multi_file_feed_id}/imports/{multi_file_feed_import_id}/direct-uploads/{upload_id}/submit

curl -X POST "https://api.oneschema.co/v0/workflows/42/imports/101/direct-uploads/555/submit" \
  -H "X-API-KEY: YOUR_API_KEY"

A successful response confirms the file has been attached to the import. Proceed to upload the next file (repeat from Step 2a) or, if all files are uploaded, move on to Step 3.

API reference: Submit a direct file upload for a Multi FileFeed import

Step 3 — Submit the Multi FileFeed Import

Once all files have been uploaded and finalized, submit the import to begin processing.

POST /v0/workflows/{multi_file_feed_id}/imports/{multi_file_feed_import_id}/submit

curl -X POST "https://api.oneschema.co/v0/workflows/42/imports/101/submit" \
  -H "X-API-KEY: YOUR_API_KEY"

Response

{
  "id": 101,
  "multi_file_feed_id": 42,
  "status": "submitted",
  "created_at": "2026-03-02T12:00:00Z"
}

The import is now queued for execution.

API reference: Submit a Multi FileFeed import

Full Example (Python)

import requests

API_KEY = "YOUR_API_KEY"
BASE_URL = "https://api.oneschema.co"
MFF_ID = 42
HEADERS = {"X-API-KEY": API_KEY}

files_to_upload = [
    {"filename": "orders.csv", "path": "./orders.csv"},
    {"filename": "customers.csv", "path": "./customers.csv"},
]

# Step 1: Create the MFF import
resp = requests.post(f"{BASE_URL}/v0/workflows/{MFF_ID}/imports", headers=HEADERS)
resp.raise_for_status()
import_id = resp.json()["id"]
print(f"Created import {import_id}")

for file_info in files_to_upload:
    # Step 2a: Create a direct upload
    resp = requests.post(
        f"{BASE_URL}/v0/workflows/{MFF_ID}/imports/{import_id}/direct-uploads",
        headers=HEADERS,
        json={"filename": file_info["filename"]},
    )
    resp.raise_for_status()
    upload = resp.json()
    upload_id = upload["upload_id"]
    presigned_url = upload["presigned_url"]
    content_type = upload["content_type"]

    # Step 2b: Upload the file to the presigned URL
    with open(file_info["path"], "rb") as f:
        put_resp = requests.put(
            presigned_url,
            headers={"Content-Type": content_type},
            data=f,
        )
        put_resp.raise_for_status()

    # Step 2c: Submit (finalize) the direct upload
    resp = requests.post(
        f"{BASE_URL}/v0/workflows/{MFF_ID}/imports/{import_id}/direct-uploads/{upload_id}/submit",
        headers=HEADERS,
    )
    resp.raise_for_status()
    print(f"Uploaded and finalized {file_info['filename']}")

# Step 3: Submit the MFF import for processing
resp = requests.post(
    f"{BASE_URL}/v0/workflows/{MFF_ID}/imports/{import_id}/submit",
    headers=HEADERS,
)
resp.raise_for_status()
print(f"Import {import_id} submitted for processing")

Quick Reference

Step	Endpoint	Method
Create import	https://docs.oneschema.co/reference/create-multi-file-feed-import	`POST`
2a. Create direct upload	https://docs.oneschema.co/reference/create-direct-upload-multi-file-feed-import-file	`POST`
2b. Upload file	(presigned URL from 2a)	`PUT`
2c. Submit direct upload	https://docs.oneschema.co/reference/submit-multi-file-feed-import	`POST`
Submit import	https://docs.oneschema.co/reference/submit-multi-file-feed-import	`POST`