You can upload and download files to and from the Catalytic platform. You can then reference those files in Fields in Workflows and Instances.

The files client allows you to upload and download files from the Catalytic platform, and to get file metadata like size, content-type and filename. It provides the following methods:

getGets metadata of a File by id
downloadDownloads a File by id
getFileStreamGets a readable stream of a File by id
uploadUploads one or more new Files

Quickstart Example

 * This example demonstrates downloading and uploading files
 * from a Workflow Instance.

const { CatalyticClient } = require('@catalytic/sdk');
const fs = require('fs');

const catalytic = new CatalyticClient();

// Search for Workflows containing "Sdk Example Workflow" in their title or description
const matches = await catalytic.workflows.find({
    query: 'Sdk Example Workflow'
// Grab the first match
const workflow = matches.workflows[0];

// Define some fields to pass to the Workflow
const fields = [
    { name: 'Age', value: 42 },
    { name: 'Name', value: 'Alice' }
// Start a new Instance of the Workflow with the provided name and fields
const instance = await catalytic.instances.start(, 'My new Instance', fields);

// Fetch the value of the `Table` field from the newly started Instance. The value will be a
// Data Table ID.
const tableId = instance.fields.find(field => === 'table').value;

// Download the Data Table as a CSV
const localFilePath = './data-table.csv';
await, 'csv', localFilePath);
const content = fs.readFileSync(localFilePath).toString();

// Update the CSV file locally, and upload to Catalytic as a new file
const updatedContent = content.replace('foo', 'bar');
fs.writeFileSync(localFilePath, updatedContent);
const uploadedFile = await catalytic.files.upload(localFilePath);

// Find the "Upload Updated Spreadsheet and Set Email" Instance Step on the Instance
const steps = (await catalytic.instances.findInstanceSteps({ instanceID: })).steps;
const uploadStep = steps.find(step => === 'Upload Updated Spreadsheet and Set Email');

// Complete the "Upload Updated Spreadsheet and Set Email" with the ID of the uploaded File
const stepFields = [{ name: 'Updated CSV', value:, 'Email Address': 'YOUR_EMAIL' }];
catalytic.instances.completeInstanceStep(, stepFields);

    `You should have an email waiting for you at ${YOUR_EMAIL} now with the updated CSV converted to an Excel attachment`