Attachments

Send file attachments (PDFs, calendar invites, images, etc.) alongside your emails.

Overview

The attachments field accepts an array of file objects. Each file must be base64-encoded. No raw MIME construction needed.

Limits

Constraint	Limit
Max attachments per email	10
Max total attachment size	40 MB (decoded)

Attachment Object

Field	Type	Required	Description
`filename`	string	Yes	The filename shown to the recipient (e.g. `"report.pdf"`).
`content`	string	Yes	Base64-encoded file content.
`contentType`	string	No	MIME type. Examples: `"application/pdf"`, `"text/calendar"`, `"image/png"`.

Examples

cURL — Calendar Invite

# Base64-encode your file
ICS_BASE64=$(base64 -i invite.ics)

curl -X POST https://api.envloped.com/v1/emails \
  -H "Authorization: Bearer en_abc123..." \
  -H "Content-Type: application/json" \
  -d "{
    \"from\": \"Your App <hello@yourdomain.com>\",
    \"to\": \"user@example.com\",
    \"subject\": \"Meeting Invite\",
    \"html\": \"<p>See the attached calendar invite.</p>\",
    \"attachments\": [{
      \"filename\": \"invite.ics\",
      \"content\": \"$ICS_BASE64\",
      \"contentType\": \"text/calendar\"
    }]
  }"

JavaScript / TypeScript (SDK)

import { EnvlopedClient } from '@envloped/envloped-js';
import { readFileSync } from 'fs';

const client = new EnvlopedClient({ apiKey: 'en_abc123...' });

const pdfBase64 = readFileSync('report.pdf').toString('base64');

await client.emails.send({
  from: 'Your App <hello@yourdomain.com>',
  to: ['user@example.com'],
  subject: 'Monthly Report',
  html: '<p>Please find the report attached.</p>',
  attachments: [
    {
      filename: 'report.pdf',
      content: pdfBase64,
      contentType: 'application/pdf',
    },
  ],
});

Go (SDK)

import (
    "encoding/base64"
    "os"

    envloped "github.com/envloped/envloped-go"
)

client := envloped.NewClient("en_abc123...")

data, _ := os.ReadFile("invite.ics")
encoded := base64.StdEncoding.EncodeToString(data)

resp, err := client.Emails.Send(&envloped.SendEmailRequest{
    From:    "Your App <hello@yourdomain.com>",
    To:      []string{"user@example.com"},
    Subject: "Meeting Invite",
    Html:    "<p>See the attached calendar invite.</p>",
    Attachments: []envloped.Attachment{
        {
            Filename:    "invite.ics",
            Content:     encoded,
            ContentType: "text/calendar",
        },
    },
})

Python

import base64
import os
import requests

with open("report.pdf", "rb") as f:
    pdf_base64 = base64.b64encode(f.read()).decode("utf-8")

response = requests.post(
    "https://api.envloped.com/v1/emails",
    headers={
        "Authorization": f"Bearer {os.environ['ENVLOPED_API_KEY']}",
        "Content-Type": "application/json",
    },
    json={
        "from": "Your App <hello@yourdomain.com>",
        "to": "user@example.com",
        "subject": "Monthly Report",
        "html": "<p>Please find the report attached.</p>",
        "attachments": [
            {
                "filename": "report.pdf",
                "content": pdf_base64,
                "contentType": "application/pdf",
            }
        ],
    },
)

Multiple Attachments

{
  "from": "hello@yourdomain.com",
  "to": "user@example.com",
  "subject": "Your order confirmation",
  "html": "<p>Receipt and calendar invite attached.</p>",
  "attachments": [
    {
      "filename": "receipt.pdf",
      "content": "JVBERi0xLjQ...",
      "contentType": "application/pdf"
    },
    {
      "filename": "delivery.ics",
      "content": "QkVHSU46VkNB...",
      "contentType": "text/calendar"
    }
  ]
}

Error Responses

Missing filename

{ "error": "Each attachment must have a filename" }

Missing content

{ "error": "Each attachment must have base64-encoded content" }

Too many attachments

{ "error": "Maximum 10 attachments allowed" }

Total size exceeded

{ "error": "Total attachment size must not exceed 40MB" }

Attachments

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