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).

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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, you can use whichever you want
  • fileSizeBytes is the exact size of the attachment in bytes (specifically, 32318 bytes is the size of Bruce’s picture above)
  • c_XXXXXXXXXXXXXXXXXXXXXXXXXX is the customer id you are uploading the attachment for. Remember to replace this!
Which would console log something like this:
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:

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Limitations

  • On emails and custom timeline entries:
    • A maximum of 25 attachments can be added
    • All attachments combined can not exceed 6MB in size
  • 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 Custom Timeline Entry or email, will be deleted after 24 hours.
  • Upload URLs are only valid for 2 hours after which a new URL needs to be created.