flow/docs/versioned_docs/version-1.9.0/API-Reference/javascript-examples/api-files/send-files-to-your-flows-v2-2.js

const url = `${process.env.FLOW_URL ?? ""}/v1/run/${process.env.FLOW_ID ?? ""}`;

const options = {
  method: 'POST',
  headers: {
    "Content-Type": `application/json`,
    "x-api-key": `${process.env.FLOW_API_KEY ?? ""}`,
  },
  body: JSON.stringify({
  "input_value": "what do you see?",
  "output_type": "chat",
  "input_type": "text",
  "tweaks": {
    "Read-File-1olS3": {
      "path": [
        "07e5b864-e367-4f52-b647-a48035ae7e5e/3a290013-fe1e-4d3d-a454-cacae81288f3.pdf"
      ]
    }
  }
}),
};

fetch(url, options)
  .then(async (response) => {
    if (!response.ok) {
      throw new Error(`HTTP ${response.status}`);
    }
    const text = await response.text();
    console.log(text);
  })
  .catch((error) => console.error(error));