Gmail API – All you need to know

30/08/2023

If you're looking to integrate Gmail into your own applications then Gmail API just what you need! Gmail is a great and reliable choice for sending emails from the web or your mobile app. Its API is safe and reliable, so your messages will not be sent to Spam. In this article, Gimasys will teach you the basics of Gmail API and detailed instructions on how you can use Gmail API to send emails.

Table of contents

What is Gmail API?

Gmail API is a set of application programming interfaces (APIs) provided by Google that allow developers to interact programmatically with Gmail. This means developers can build apps, integrations, or tools that can access and manipulate Gmail data, perform actions like sending or receiving emails, and label and create drafts, along with other functions, all in a more efficient way than traditional IMAP.

How to integrate Gmail API into App

The following steps will enable the Gmail API in your project:

Step 1: Go to API Console.
Step 2: Select a project from the list or create a new project.
Step 3: If the control panel doesn't open, click the left menu to open it manually.
Step 4: Use the search field to find the API if you don't see it.
Step 5: Click Enable

Note: Activation will vary depending on the API type. Some APIs will require you to accept their Terms and Conditions before you can activate them. Other APIs may ask you for additional information, such as your contact information or the name of the app being developed.

If you are asked for additional information, that information will not be shared with anyone other than Google. Google uses this information to understand API usage and to contact you about usage.

Refer: Instructions on how to set up Gmail SMTP settings

How to use Gmail API

Gmail API can be used to send and receive emails, manage contacts, create labels and filters, etc. To use Gmail API, you need to create a project at Google's API Console. You also need to enable Gmail API in your project and get credentials for authentication.

You can then choose the quick start guide or dig through the documentation. The Gmail API is accessed through a client library provided by Google.

Connect your Gmail account to your app

Before you can access your Gmail accounts, you must authenticate them with the appropriate permissions. This token grants limited access to user resources to the extent the user agreed to as part of the authentication process.

How to compose and send emails using Gmail API

The Gmail API allows you to create and send drafts. A draft is basically an unsent message, it can be created by embedding the MIME message in the base64url string. You can replace the content of the draft with a different MIME encoded message using the update draft method.

The received draft can be used to retrieve the draft content in raw format. The send draft method sends the specified draft.

Gmail webhook notifications

The Gmail API provides webhook notifications that allow you to monitor the creation, deletion, and labeling of emails and labels in a user's Gmail account. This saves time and allows you to avoid having to probe users' emails looking for new data.

Notifications for Gmail are sent via Google Cloud Pub, Sub API. This API allows you to receive updates about your Gmail account via webhooks. You will need to create a Cloud Pub/Sub topic to enable Gmail notifications.

Gmail API webhook notification history is the most important resource component. This is a revised collection of messages in chronological order. This synchronization method stores all modifications to a Gmail account.

Google states that historical changes are typically available for seven days. They are not always available and may not be available for longer periods. Historical resources should only be used for immediate synchronization.

To synchronize large amounts of data for account users, you can use messages.

The history resource allows you to track changes to your Gmail account, sending viewing requests through the Gmail API. This request will expire after seven days. If you need to track changes beyond this time, additional tracking will be required.

How to attach and upload files

You can upload files to Gmail through the Gmail API in one of three ways

Uploading is the easiest way to do it. However, it can only upload files up to 5MB in size, and you can't include metadata.
Multipart uploads are better if you upload smaller files or want to include metadata.
Resumable upload is the third and best option if you have unreliable network conditions and large files.

In conclusion

Gmail API gives you RESTful access to all the features you normally get with Gmail, including sending and receiving HTML emails, sending and receiving attachments, and performing CRUD operations with messages, drafts, strings and labels.

You also have full control over your Gmail inbox and can perform specific queries using the web UI's search capabilities.

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