This page outlines how to upload attachments programmatically. At a high level to upload attachments you:
  • Make an API call to get an an upload url and some metadata
  • You then upload your file, and metadata to that upload url.
  • Use the ID of the attachment you uploaded in other API calls (e.g. create a thread or send an email).

​
Step by step guide

To try this, you will need an API key with the following permission:
  • attachment:create
1

Creating an upload url

  • fileName is the name under which the attachment will appear in the timeline
  • fileSizeBytes is the exact size of the attachment in bytes
  • c_XXXXXXXXXXXXXXXXXXXXXXXXXX is the customer id you are uploading the attachment for
import { AttachmentType, PlainClient } from '@team-plain/typescript-sdk';

const client = new PlainClient({ apiKey: 'plainApiKey_xxx' });

const res = await client.createAttachmentUploadUrl({
  customerId: 'c_XXXXXXXXXXXXXXXXXXXXXXXXXX',
  fileName: 'the-filename.jpeg',
  fileSizeBytes: 32318,
  attachmentType: AttachmentType.CustomTimelineEntry,
});

if (res.error) {
  console.error(res.error);
} else {
  console.log('Attachment upload url created');
  console.log(res.data);
}
Which would console log something like this:
{
  "__typename": "AttachmentUploadUrl",
  "attachment": {
    "__typename": "Attachment",
    "id": "att_01H3970W7XG1716AVNGQ6FWYGD",
    "fileName": "the-filename.jpeg",
    "fileSize": {
      "__typename": "FileSize",
      "kiloBytes": 32.32,
      "megaBytes": 0.03
    },
    "fileExtension": null,
    "updatedAt": {
      "__typename": "DateTime",
      "iso8601": "2023-06-19T06:56:04.349Z",
      "unixTimestamp": "1687157764349"
    }
  },
  "uploadFormUrl": "https://prod-uk-services-attachm-attachmentsuploadbucket2-1l2e4906o2asm.s3.eu-west-2.amazonaws.com/",
  "uploadFormData": [
    { "key": "acl", "value": "private" },
    { "key": "x-amz-server-side-encryption", "value": "AES256" },
    { "key": "Content-Type", "value": "application/octet-stream" },
    {
      "key": "bucket",
      "value": "prod-uk-services-attachm-attachmentsuploadbucket2-1l2e4906o2asm"
    },
    { "key": "X-Amz-Algorithm", "value": "AWS4-HMAC-SHA256" },
    {
      "key": "X-Amz-Credential",
      "value": "ASIAWYWBOL266XVGRRM7/20230619/eu-west-2/s3/aws4_request"
    },
    { "key": "X-Amz-Date", "value": "20230619T065604Z" },
    {
      "key": "X-Amz-Security-Token",
      "value": "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"
    },
    {
      "key": "key",
      "value": "w_01GZEA2KYR63P8E00JBMYQT58Z/pending/machineUser/mu_01GZEA2M91124MPFAVZEPKC2MY/att_01H3970W7XG1716AVNGQ6FWXGD"
    },
    {
      "key": "Policy",
      "value": "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"
    },
    {
      "key": "X-Amz-Signature",
      "value": "a68a18898e654e072f80b052853b0722aa58aada15d3cd3e9cc937f929ff2433"
    }
  ],
  "expiresAt": {
    "__typename": "DateTime",
    "iso8601": "2023-06-19T08:56:04.348Z",
    "unixTimestamp": "1687164964348"
  }
}
2

Uploading the attachment

In the AttachmentUploadUrl we created in the previous step we get back 2 fields which are needed to actually upload our attachment:
  • uploadFormUrl: The URL to which to upload the file to
  • uploadFormData: A list of key, value pairs that have to be included in the data we upload along with the actual file data.
With this information we can now upload our actual file to Plain. To do this we need to build a form (multipart/form-data) with the data contained in uploadFormData and submit it to the uploadFormUrl.Here is some example code showing how you would do this in the Browser and from a Node server:
/**
 * Upload an attachment.
 *
 * @param {Blob} fileBlob blob with the contents of the file to upload
 * @param {string} uploadFormUrl The url to post the form to (from `createAttachmentUploadUrl.attachmentUploadUrl.uploadFormUrl`)
 * @param {{ key: string; value: string }[]} uploadFormData Data to be added to the form along with the file contents (from `createAttachmentUploadUrl.attachmentUploadUrl.uploadFormData`)
 */
function uploadAttachment(fileBlob, uploadFormUrl, uploadFormData) {
  const form = new FormData();
  uploadFormData.forEach(({ key, value }) => {
    form.append(key, value);
  });

  const file = new File([fileBlob], 'file');
  form.append('file', file);

  console.log(`Uploading attachment to ${uploadFormUrl}`);

  fetch(uploadFormUrl, {
    method: 'POST',
    body: form,
  })
    .then((res) => {
      if (!res.ok) {
        throw new Error(response.statusText);
      }
      console.log(`File successfully uploaded! (code=${res.status})`);
    })
    .catch((err) => {
      console.log(`There was an error uploading the file: %s`, err.message ? err.message : err);
    });
}

​
Limitations

  • A maximum of 100 attachments can be added to a message
  • The combined size of all attachments you add to a message cannot exceed the following limits based on attachment type:
    • Email attachments: 6MB
    • Chat attachments: 100MB
    • Slack attachments: 50MB
    • Microsoft Teams attachments: 50MB
    • Discord attachments: 50MB
    • Thread discussion attachments: 50MB
    • Note attachments: 50MB
  • The following file extensions are not allowed as attachments: bat, bin, chm, com, cpl, crt, exe, hlp, hta, inf, ins, isp, jse, lnk, mdb, msc, msi, msp, mst, pcd, pif, reg, scr, sct, shs, vba, vbe, vbs, wsf, wsh, wsl
  • Attachments uploaded, but never referenced by a message, will be deleted after 24 hours.
  • Upload URLs are only valid for 2 hours after which a new URL needs to be created.