---
title: File uploads
description: Send and receive files across chat platforms.
type: guide
prerequisites:
  - /docs/usage
---

# File uploads



## Send files

Attach files to messages using the `files` property:

```typescript title="lib/bot.ts" lineNumbers
const reportBuffer = Buffer.from("PDF content");

await thread.post({
  markdown: "Here's the report you requested:",
  files: [
    {
      data: reportBuffer,
      filename: "report.pdf",
      mimeType: "application/pdf",
    },
  ],
});
```

### Multiple files

```typescript title="lib/bot.ts" lineNumbers
await thread.post({
  markdown: "Attached are the images:",
  files: [
    { data: image1, filename: "screenshot1.png" },
    { data: image2, filename: "screenshot2.png" },
  ],
});
```

### Files without text

```typescript title="lib/bot.ts" lineNumbers
await thread.post({
  markdown: "",
  files: [{ data: buffer, filename: "document.xlsx" }],
});
```

## Receive files

Access attachments from incoming messages:

```typescript title="lib/bot.ts" lineNumbers
bot.onSubscribedMessage(async (thread, message) => {
  for (const attachment of message.attachments ?? []) {
    console.log(`File: ${attachment.name}, Type: ${attachment.mimeType}`);

    if (attachment.fetchData) {
      const data = await attachment.fetchData();
      console.log(`Downloaded ${data.length} bytes`);
    }
  }
});
```

### Attachment properties

| Property    | Type                               | Description                             |
| ----------- | ---------------------------------- | --------------------------------------- |
| `type`      | `string`                           | Attachment type (e.g., "image", "file") |
| `url`       | `string` (optional)                | Public URL                              |
| `name`      | `string` (optional)                | Filename                                |
| `mimeType`  | `string` (optional)                | MIME type                               |
| `size`      | `number` (optional)                | File size in bytes                      |
| `width`     | `number` (optional)                | Image width                             |
| `height`    | `number` (optional)                | Image height                            |
| `fetchData` | `() => Promise<Buffer>` (optional) | Download the file data                  |