Skip to main content

Upload a file

This recipe uploads a file to a Unity Catalog volume using the Databricks SDK for Python.

Code snippet​

app.py
import io
import streamlit as st
from databricks.sdk import WorkspaceClient

w = WorkspaceClient()

uploaded_file = st.file_uploader(label="Select file")

upload_volume_path = st.text_input(
    label="Specify a three-level Unity Catalog volume name (catalog.schema.volume_name)",
    placeholder="main.marketing.raw_files",
)

if st.button("Save changes"):
    file_bytes = uploaded_file.read()
    binary_data = io.BytesIO(file_bytes)
    file_name = uploaded_file.name

    parts = upload_volume_path.strip().split(".")

    catalog = parts[0]
    schema = parts[1]
    volume_name = parts[2]

    volume_file_path = f"/Volumes/{catalog}/{schema}/{volume_name}/{file_name}"
    w.files.upload(volume_file_path, binary_data, overwrite=True)

Resources​

Permissions​

Your app service principal needs the following permissions:

  • USE CATALOG on the catalog of the volume
  • USE SCHEMA on the schema of the volume
  • READ VOLUME and WRITE VOLUME on the volume

See Privileges required for volume operations for more information.

If you declare volume access in a Databricks Asset Bundle, resources.apps[*].resources[*].uc_securable may not grant USE_CATALOG and USE_SCHEMA on the parent catalog and schema (the app still needs them at runtime). As a temporary workaround until bundles can declare those parent grants, add the privileges manually, or see apps_grants_sync: an example Databricks App and Asset Bundle that wires experimental.scripts.postdeploy so parent privileges are applied after each databricks bundle deploy (copy its tools/ into your bundle or mirror the same pattern in databricks.yml).

Dependencies​

requirements.txt
databricks-sdk
streamlit