Q:

using ruby to extract email body from Microsoft graph rest api outlook message

I am fetching emails from Outlook through Microsoft Graph or Rest Api directly from Ruby without using any Microsoft SDK.
The problem I am facing is that I can't get the email message body from the response returned by Microsoft. Using the Ruby Mail gem, I have tried to parse the response by doing:
 response = HTTParty.get("https://graph.microsoft.com/v1.0/me/messages", headers: headers)

response_body = response.body
parsed_body = JSON.parse(response_body)
returned_email_values = parsed_body.dig('value')
first_email = returned_email_values.first
#I tried mail = Mail.read_from_string(first_email ) and also, mail = Mail.new(first_email )

mail = Mail.read_from_string(first_email )
mail.body.raw_source     

which returns:
 "{\"contentType\"=>\"html\", \"content\"=>\"<html>\\r\\n<head>\\r\\n<meta http-equiv=\\\"Content-Type\\\" content=\\\"text/html; charset=utf-8\\\">\\r\\n<meta content=\\\"text/html; charset=utf-8\\\">\\r\\n</head>\\r\\n<body>\\r\\nLet's go&nbsp;\\r\\n<div><br>\\r\\n</div>\\r\\n<div style=\\\"font-size:100%; color:#000000\\\">\\r\\n<div>-------- Original message --------</div>\\r\\n<div>From: Well &lt; **@outlook.com&gt; </div>\\r\\n<div>Date: 09/01/2018 22:33 (GMT&#43;00:00) </div>\\r\\n<div>To: **@yahoo.com </div>\\r\\n<div>Subject: it is httparty </div>\\r\\n<div><br>\\r\\n</div>\\r\\n</div>\\r\\nhttparty rocks\\r\\n</body>\\r\\n</html>\\r\\n\"}"

How do I parse this so I get the email body text, without the html markdown which should return httparty rocks.
For reference, here is a link to Microsoft's documentation for the api and this is the full api response that is returned to me:
- "@odata.etag": W/"CQAAABYAA***hjCagexQJczqiL***dRAAAxqsAe"
id: ****TAwCgBGAAAD2TG**i9L9AAAgE2n4YwmoHsUCXM6***
createdDateTime: '2018-01-09T23:07:52Z'
lastModifiedDateTime: '2018-01-09T23:07:52Z'
changeKey: **AAADafhjCag**JczqiL0v2dRAAA**
categories: []
receivedDateTime: '2018-01-09T23:07:52Z'
sentDateTime: '2018-01-09T23:08:36Z'
hasAttachments: false
internetMessageId: "<**FT028.enam01.prod.protection.outlook.com>"
subject: 'Re: it is httparty'
bodyPreview: "Let's go\r\n\r\n---- Original message -----\r\nFrom: Well <***@outlook.com>\r\nDate: 09/01/2018 22:33 (GMT+00:00)\r\nTo: ***@yahoo.com\r\nSubject: it is httparty\r\n\r\nhttparty rocks"
importance: normal
parentFolderId: **1LTgyOTYtMDACLTAwCA**0aVdJhhKHRI1AEA2**
conversationId: **NiZmYAZC0wYTc**gyOtMDACLTAwCg**
isDeliveryReceiptRequested: 
isReadReceiptRequested: false
isRead: false
isDraft: false
webLink: https://outlook.live.com/owa/?ItemID=****1AcA2n4Yw**%3D&exvsurl=1&viewmodel=ReadMessageItem
inferenceClassification: focused
body:
  contentType: html
  content: "<html>\r\n<head>\r\n<meta http-equiv=\"Content-Type\" content=\"text/html;
  charset=utf-8\">\r\n<meta content=\"text/html; charset=utf-8\">\r\n</head>\r\n<body>\r\nLet's
  go&nbsp;\r\n<div><br>\r\n</div>\r\n<div style=\"font-size:100%; color:#000000\">\r\n<div>--------
  Original message --------</div>\r\n<div>From: Well &lt; **@outlook.com&gt;
  </div>\r\n<div>Date: 09/01/2018 22:33 (GMT&#43;00:00) </div>\r\n<div>To: ***@yahoo.com
  </div>\r\n<div>Subject: it is httparty </div>\r\n<div><br>\r\n</div>\r\n</div>\r\nhttparty
  rocks\r\n</body>\r\n</html>\r\n"
sender:
   emailAddress:
     name: well
     address: ***@yahoo.com
from:
  emailAddress:
    name: well
    address:***@yahoo.com
toRecipients:
  - emailAddress:
     name: bee
     address: **@outlook.com
ccRecipients: []
bccRecipients: []
replyTo: []

A:

Probably the easiest way to do this is to ask the server to return the plain-text version of the body. From the docs:
Prefer: outlook.body-content-type: The format of the body and uniqueBody properties to be returned in. Values can be "text" or "html". If the header is not specified, the body and uniqueBody properties are returned in HTML format. Optional.
Here's how I specified the header in Postman:

