Python Gmail API

Introduction

Gmail API is a powerful and easy-to-use Google API that can be integrated in any Python application. This API allows you to access and manage the Gmail messages, labels, drafts, and history. You can send emails, get emails, search emails, reply emails, and delete emails using the Gmail API.

Syntax

First, you need to enable the Gmail API for your Google account and install the google-auth, google-auth-oauthlib, and google-auth-httplib2 Python libraries. Then, you can authenticate and authorize the API using the following code snippet:

from google.oauth2.credentials import Credentials

creds = Credentials.from_authorized_user_file('path_to_credentials.json', SCOPES)

where path_to_credentials.json is the path to the credentials file and SCOPES are the permissions you want to grant to the API (e.g., ['https://www.googleapis.com/auth/gmail.readonly'] for read-only access).

Once you have authenticated and authorized the API, you can use the following methods to interact with the Gmail:

Send email

from googleapiclient.discovery import build
from googleapiclient.errors import HttpError
from google.oauth2.credentials import Credentials
import base64
from email.mime.text import MIMEText
from email.mime.multipart import MIMEMultipart
from email.mime.image import MIMEImage

def send_email(to, subject, body, image=None):
    try:
        service = build('gmail', 'v1', credentials=creds)
        message = MIMEMultipart()
        text = MIMEText(body, 'html')
        message.attach(text)
        if image:
            img = MIMEImage(open(image, 'rb').read(), name='image.png')
            message.attach(img)
        message['to'] = to
        message['subject'] = subject
        create_message = {'raw': base64.urlsafe_b64encode(message.as_bytes()).decode()}
        send_message = (service.users().messages().send(userId="me", body=create_message).execute())
        print(F'sent message to {to} Message Id: {send_message["id"]}')
    except HttpError as error:
        print(F'An error occurred: {error}')
        send_message = None
    return send_message

Get email

def get_email(email_id):
    service = build('gmail', 'v1', credentials=creds)
    message = service.users().messages().get(userId='me', id=email_id, format='full').execute()
    payload = message['payload']
    headers = payload['headers']
    for d in headers:
        if d['name'] == 'From':
            sender = d['value']
        if d['name'] == 'Delivered-To':
            recipient = d['value']
        if d['name'] == 'Subject':
            subject = d['value']
        if d['name'] == 'Date':
            date = d['value']
    parts = payload['parts']
    for part in parts:
        data = part['body']['data']
    print(F'From: {sender}, To: {recipient}, Subject: {subject}, Date: {date}, Body: {data}')

Search email

def search_email(query):
    service = build('gmail', 'v1', credentials=creds)
    result = service.users().messages().list(userId='me', q=query).execute()
    messages = result.get('messages', [])
    for msg in messages:
        get_email(msg['id'])

Delete email

def delete_email(email_id):
    service = build('gmail', 'v1', credentials=creds)
    delete_message = service.users().messages().delete(userId='me', id=email_id).execute()
    print(F'message deleted: {delete_message}')

Example

Here is an example of how to send an email using the Gmail API:

to = 'example@example.com'
subject = 'Test Email'
body = '<h1>Hello from Gmail API</h1>'
image = 'image.png'
send_email(to, subject, body, image)

Output

The above code will send an email to the specified recipient with subject "Test Email" and body "Hello from Gmail API" and an image named "image.png" attached to it.

Explanation

The send_email method creates a MIME message object, adds a HTML body and an inline image to it, sets the recipient and subject, encodes the message in base64, and sends it using the service.users().messages().send() method.

The get_email method retrieves the message with the specified ID, extracts the sender, recipient, subject, date, and body from its payload, and prints them to the console.

The search_email method searches for the messages matching the specified query (e.g., "from:jane@example.com subject:hello"), and calls the get_email method to print their details.

The delete_email method deletes the message with the specified ID from the Inbox.

Use

You can use the Gmail API to build email clients, email marketing tools, email automation scripts, and many other email-related applications. The API provides a convenient and secure way to access and manage your Gmail messages programmatically.

Important Points

• To use the Gmail API, you need to create a Google Cloud Platform project, enable the Gmail API, and obtain credentials for your application.
• You can authenticate and authorize the API using the google-auth library and the OAuth2 protocol.
• You can interact with the Gmail API using the google-api-python-client library, which provides a Python wrapper around the Gmail REST API.
• The Gmail API supports a wide range of operations, such as sending emails, getting emails, searching emails, and deleting emails. You can also manage labels, drafts, and history using the API.
• The Gmail API has rate limits and quotas that you need to respect in order to avoid errors and disruptions.

Summary

In this tutorial, you learned how to use the Gmail API in Python to send and receive emails, search for messages, and delete messages. You also learned how to authenticate and authorize the API, and how to use the google-api-python-client library to interact with the Gmail REST API.