google apps script - How can I get the subject of an email gmail python API

Question

def getbodyinbox():
    service = build('gmail', 'v1', credentials=creds)
    label_name = "READ-BY-SCRIPT"
    label_id = 'Label_8507504117657095973'
    results = service.users().messages().list(
        userId='me', q="-label:"+label_name, maxResults=1).execute()
    messages = results.get('messages', [])
    body = []
    if not messages:
        body = "no messages"
        return body
    else:
        for message in messages:
            msg = service.users().messages().get(
                userId='me', id=message['id']).execute()
            labels = msg['labelIds']
            if "INBOX" in labels:
                headers = msg['payload']['headers']
                headers = str(headers)
                print(headers)
                if "class_ix" in headers:
                    body.append(msg['payload']['parts'])
                    if 'data' in body[0][0]['body']:
                        body = base64.urlsafe_b64decode(
                            body[0][0]['body']['data'])
                    elif 'data' in body[0][1]['body']:
                        body = base64.urlsafe_b64decode(
                            body[0][1]['body']['data'])
                    body = str(body)

                        
                    return body


print(getbodyinbox())

This is my code so far with the part that gets the credentials and all of the imports removed. It gets the body of the most recent email without a label 'READ-BY-SCRIPT' that also has the label INBOX. How can I get the subject of the email instead of the body?

question from:https://stackoverflow.com/questions/65843334/how-can-i-get-the-subject-of-an-email-gmail-python-api

Answer 1

Have a look at the message resource, MessagePart and header

The structure is the following:

  "payload": {
    "partId": string,
    "mimeType": string,
    "filename": string,
    "headers": [
      {
        "name": string,
        "value": string
      }
    ],

and:

So, in other words, the subject is contained in the headers.

You can retrieve in Python with

headers = msg['payload']['headers']
subject= [i['value'] for i in headers if i["name"]=="Subject"]