multipart/form-data can be sent as shown in the following example with image attachment:
POST / HTTP/1.1
HOST: platform.ringcentral.com/restapi/v1.0/account/~/extension/~/sms
Authorization: Bearer <MyToken>
Content-Type: multipart/form-data; boundary=12345
--12345
Content-Disposition: form-data; name="to"
+16505550101
--12345
Content-Disposition: form-data; name="to"
+16505550102
--12345
Content-Disposition: form-data; name="from"
+16505550100
--12345
Content-Disposition: form-data; name="text"
Hello World
--12345
Content-Disposition: form-data; name="attachment" filename="picture.jpg"
content of picture.jpg ...
--12345--
This can be done using curl as follows:
curl -XPOST https://platform.ringcentral.com/restapi/v1.0/account/~/extension/~/sms \
-H 'Authorization: Bearer <MyToken>' \
-F 'to=+16505550101' \
-F 'to=+16505550102' \
-F 'from=+16505550100' \
-F 'text=Hello World' \
-F 'attachment=@picture.jpg'
References :