Creating a Gmail integration using custom connectors

Creating a Gmail integration using custom connectors

Hello everyone!

Greetings from Deluge. Following up on our series aimed at exploring the capabilities of Deluge, today we'll take an in-depth look into the Deluge custom connections that can be created across Zoho services.

Deluge boasts an extensive range of over 260 built-in integrations spanning more than 35 Zoho services. These integrations streamline data access and modification with these services, from a single point in Zoho, without having to toggle between services. However, we understand that the needs of our users vary widely, and sometimes existing integrations may not cover every scenario.

That's where custom connections come in. Think of them as the Swiss Army Knife of integrations, enabling connections with hundreds of services—such as Gmail and Outlook—and seamlessly integrating them with your favorite Zoho services. With custom connections, you have the power to build your own integrations with virtually any third-party service and tailor them to meet your requirements. Moreover, since the custom connections use the OAuth 2.0 authentication mechanism, you're getting best-in-class security while integrating with third-party services.

What are connections? 
Before we dive into the details of custom connectors, let's take a glimpse at what connections are in Deluge. Connections are a means to connect your Zoho account and any third-party accounts you wish to integrate with. Once a connection is created and connected, you can use it in Deluge integration tasks or invokeURL scripts to perform REST operations on the target service from the required Zoho service. For more information, visit our Connections help doc.
  
Use case 
Assume the sales team of an organization uses Zoho CRM for managing leads, customer retention, and customer acquisition, and uses Gmail for communication purposes, like following up with potential clients via email.   While the system works as is, it's time-consuming and prone to error, so an integration between Gmail and Zoho CRM is necessary to improve efficiency.

A custom connection to your Google account will enable you to sync your Zoho CRM and Google accounts, allowing you to perform actions related to your Google account from Zoho CRM. For example, you can invoke the connection using the invokeURL task in Zoho CRM and send an email to your leads from your Gmail address.

Steps to configure the Google custom connection

Configuration video


Configuration steps
Creating Google OAuth credentials
  1. Visit https://console.cloud.google.com/.
  2. Click the dropdown and choose the required project.
  3. Navigate to the hamburger menu on the left and click APIs and services -> Library.
  4. You'll be taken to the API library page. Navigate to the Google Workspace section and click Gmail API.
  5. Next, click Enable on the Gmail API product details page.
  6. In order to use this API, you'll need to create credentials. Click CREATE CREDENTIALS.
  7. On the Create credentials page, choose Gmail API in the Select an API dropdown and User Data under the What data will you be accessing? section. Click Next.
  8. Next, on the OAuth consent screen, enter the App name, User support email, and Developer contact email address. Then click Save and Continue.
  9. Next, under the Scopes section, click the ADD OR REMOVE SCOPES button.
  10. In the Update selected scopes pane, search and select the gmail.readonly scope. Click Update, and then click Save and continue.


  11. Now, under the OAuth Client ID section, choose Web application in the Application type dropdown. Then name your app.


  12. Enter https://deluge.zoho.com/delugeauth/callback as the Authorized redirect URI.
  13. Click Create and download your credentials. This Client ID and others will be required later, while creating a connection in Zoho CRM.
  14. Navigate to the OAuth consent screen and click Add users under Test users. Enter the user's email address and click Save.
Creating a custom connector for Gmail
  1. Now the action shifts to Zoho CRM. Navigate to crm.zoho.com -> Settings -> Connections.
  2. Choose Custom Services and click Create Service.
  3. On the Create Service screen, choose OAuth 2.0 as the Authentication type and Header as the Parameter.
  4. Enter the Client ID, Client Secret, and Authorize URL generated from Google as shown in step 12 above.
    Tip: Having the Offline access type will allow your application to refresh tokens even when the user is not actively using the application.
  5. Then enter https://oauth2.googleapis.com/token as the Access token URL and Refresh token URL.
  6. Specify the necessary scopes like read and create, etc. and then click Create Service.
  7. On the next page, click Create Connection. Give the connection name and choose the scopes. Then click Create and Connect.
  8. Finally, authenticate the connection on the Google accounts page. Your custom connection will be created, and the two services can be integrated!
Now that the connection between Zoho CRM and Gmail has been established, you can use the invokeURL task to access and modify data in Gmail using the different APIs.

Sample
You can use the below code in invokeURL task to get the latest emails from Gmail.

userId = "emailaddress@gmail.com";
get_gmail = invokeurl
[
url: "https://gmail.googleapis.com/gmail/v1/users/"+userId+"/messages"
type: GET
connection : "connectionname"
];
messageID = get_gmail.get("messages").get(0).get("id");

get_gmail_withID = invokeurl
[
url: "https://gmail.googleapis.com/gmail/v1/users/"+userId+"/messages/"+messageID
type: GET
connection : "connectionname"
];

Content_of_the_mail = get_gmail_withID.get("snippet");
info "Mail Content : " + Content_of_the_mail;

gmail_values = get_gmail_withID.get("payload").get("headers");
for each headers in gmail_values
{
if ( headers.get("name") == "Subject" )
{
info "Subject of the Mail : " + headers.get("value");
}
if ( headers.get("name") == "From" )
{
info "From Address : " + headers.get("value");
}
}

References

----

And that's a wrap for today! We hope you found this post informative and start using custom connections to experience the full capabilities of Deluge and Zoho.

Kindly let us know if you have any questions, feedback, or suggestions in the comments, or write to us at support@zohodeluge.com!
 
Regards,
The Deluge Team

      Zoho Campaigns Resources


        • Desk Community Learning Series


        • Digest


        • Functions


        • Meetups


        • Kbase


        • Resources


        • Glossary


        • Desk Marketplace


        • MVP Corner


        • Word of the Day


        • Ask the Experts


          Zoho CRM Plus Resources

            Zoho Books Resources


              Zoho Subscriptions Resources

                Zoho Projects Resources


                  Zoho Sprints Resources


                    Zoho Orchestly Resources


                      Zoho Creator Resources


                        Zoho WorkDrive Resources



                          Zoho CRM Resources

                          • CRM Community Learning Series

                            CRM Community Learning Series


                          • Tips

                            Tips

                          • Functions

                            Functions

                          • Meetups

                            Meetups

                          • Kbase

                            Kbase

                          • Resources

                            Resources

                          • Digest

                            Digest

                          • CRM Marketplace

                            CRM Marketplace

                          • MVP Corner

                            MVP Corner




                            Zoho Writer Writer

                            Get Started. Write Away!

                            Writer is a powerful online word processor, designed for collaborative work.

                              Zoho CRM コンテンツ






                                ご検討中の方

                                  • Recent Topics

                                  • Set Custom Icon for Custom Modules in new Zoho CRM UI

                                  • Live Webinar: Getting Started with Zoho WorkDrive - A Complete Overview

                                    Hello everyone, We’re excited to invite you to our upcoming live webinar! Discover how to set up your team, bring in your data, and make the most of WorkDrive’s collaboration, organization, AI, and security capabilities. This session is perfect for anyone
                                  • Marketing Tip #4: Build your email list early

                                    Email marketing has one of the highest returns on investment. Don’t wait until later; start collecting subscribers now. When you've got their attention, you can send them emails about offers, new product launches, seasonal greetings, and more. Try this
                                  • Is anyone else having trouble saving a custom image in their email signature, or is it just me?

                                    When I try to save the image I get an error that says "Operation Failed" I opened a support ticket two weeks ago and received a response that it would be debugged, but it still isn’t working
                                  • Unify Overlapping Functionalities Across Zoho Products

                                    Hi Zoho One Team, We would like to raise a concern about the current overlap of core functionalities across various Zoho applications. While Zoho offers a rich suite of tools, many applications include similar or identical features—such as shift management,
                                  • Zoho Desk Domain mapping / Cloudflare CNAME not recognized

                                    Hello, my website is behind Cloudflare and SSL. From the Cloudflare control panel I added a CNAME record such as support.mydomain.com pointing to desk.cs.zohohost.com but I'm stuck with the message "Make sure you've mapped the CNAME entry..."
                                  • Power of Automation :: Quick way to associate your Projects with Zoho CRM

                                    A custom function is a software code that can be used to automate a process and this allows you to automate a notification, call a webhook, or perform logic immediately after a workflow rule is triggered. This feature helps to automate complex tasks and
                                  • Create an Eye-Catching Announcement Widget for Your Help Center

                                    Hello Everyone! In this week’s edition, let’s explore how to keep your customers updated with exciting news in the Help Center. See how ZylkerMobile wowed their customers by bringing updates right to their portal. ZylkerMobile, the renowned brand for
                                  • I want to add my other zoho account in same pc

                                    why does zoho restrict me doing many things as i also want to add my second mail account bit its not allowing me to do that
                                  • Search in Zoho Community Not Working

                                    I realize this is a bit of a meta topic, but the search for the various Zoho Communities appears to not be working. I'm under the impression that they run on some version of the Zoho Desk platform, so I'm posting this here.
                                  • Capture Stripe’s Customer ID

                                    Does anyone know of a way to capture Stripe’s customer ID that is created when the form/payment is processed? I would like to have the customer ID stored in our CRM so we could utilize in some custom functions down the road.
                                  • Custom Modules - Where are Comments??

                                    In the standard ticket module and in the tasks module, we have an interactive comment box that we can post important details/notes and can tag others if needed. Where is this functionality for Custom Modules? Ideally, custom modules would have very similar,
                                  • Dynamic Signature - Record owner

                                    Hi everyone, I’m using Zoho Writer merge templates from Zoho CRM and have two questions: Owner signature: How can I automatically insert the CRM record owner’s signature in the merged document? I’m not sure where this signature is stored or how to reference
                                  • Color of Text Box Changes

                                    Sometimes I find the color of text boxes changed to a different color. This seems to happen when I reopen the same slide deck later. In the image that I am attaching, you see that the colors of the whole "virus," the "irology" part of "virology," and
                                  • PUNJAB NATIONAL BANK (CORPORATE) INDIA - NOT AVAILABLE IN BANKING

                                    Dear sir, Kindly fix it. PUNJAB NATIONAL BANK (INDIA) is available but PUNJAB NATIONAL BANK (CORPORATE) is not available. Kindly enable this banking since we need to categorize the entries. Regards, Sanjay Jena email id/ user id : travewithmerchant@
                                  • Amazon invoice in Zoho Books

                                    I have just made my first few sales on Amazon India. Amazon Seller account generates invoices for the sales made on Amazon. These invoices are sent to customers also. Now when I was only making offline sales, I used to create Invoices in Zoho Book. Now
                                  • CUSTOM FUNCTION GIVE ERROR #EVAL!

                                    CUSTEM FUNCTION CREATE KYA ZOHOSHEET ME US FUNCTION KO USE KIYA LEKIN DATA TO SAHI HAI LAKIN DATA SHEET ME NAHI LAG LAHA HAI KRUPYA SOLVE KARE MY CODE IS float ADDTWO_TWO(float NO1, float NO2) { ADD = NO1 + NO2; return ADD; }
                                  • Zoho ShowTime: Certificates of Completion - Award your learners with a sense of achievement

                                    In our increasingly competitive market, professional trainers need to differentiate themselves if they are to survive. One way to do this is to focus on innovation and deliver an ideal learning experience. By developing a renowned certificate program that provides learners with a specialized skill set for a particular industry, both trainees and future prospects will recognize the trainer's leadership in that field. This can help with long-term growth, revenue generation, and even marketing and branding.
                                  • Shortcut to fill a range of cells

                                    Good evening: I'm writing because I haven't been able to find a feature that allows you to select a range of cells, type in one of them, and then use a key combination to type in all of them. In Excel, the keyboard shortcut is Ctrl+Enter. I haven't found
                                  • Playback and Management Enhancements for Zoho Quartz Recordings

                                    Hello Zoho Team, We hope you're all doing well. We would like to submit a feature request related to Zoho Quartz, the tool used to record and share browser sessions with Zoho Support. 🎯 Current Functionality As of now, Zoho Quartz allows users to record
                                  • IMAP Migration from Gmail

                                    I have been trying to import my email from a Gmail server and keep receiving the following error. I have reduced the security, activated imap and no improvement. The link to the Google support item has not helped. Unable to connect to your account. Please
                                  • Your Incoming has been blocked and the emails will not be fetched in your Zoho account and POP Accounts Click here to get unblocked.

                                    When entering my account, this error is thrown at me, and I deleted a good part of my deleted messages, but I still can not unblock it, I would appreciate your help. reservas@lineasperutravel.com
                                  • Request for Creating Multiple Email Accounts on One Mobile Number

                                    Dear Zoho Team, I am planning to shift all my work-related communication to Zoho Mail because of its reliability and features. For my work, I need to create 3–4 separate email accounts for different purposes. Could you please confirm if it is possible
                                  • Signature issue

                                    Problem: The signature does not appear when replying or forwarding an email. solve issue: settintgs/Signature Check option place a signature above the content with quotation marks
                                  • mail admin not loading

                                    i am trying to login to mailadmin ... gears keeps rotating forever... its not a password issue whats so ever ... not cookies issues whatsoever from android app i can login but there so few things to do from there .. i changed ip address the same... i
                                  • Unify All Zoho Video Meeting Experiences into One Standardized Platform

                                    Hi Zoho Team, We would like to share an important user experience concern regarding the current state of video meeting functionality across the Zoho ecosystem. The Problem Within Zoho, there are multiple ways to initiate or schedule a video meeting: Zoho
                                  • Changing Account in Quote form does not update address information.

                                    I am trying to update the address information in a quote I've created. I corrected the address in the "Account" but that did not change in the quote. If I re-enter the Account Name in the Quote form, nothing updates. How do I fix this?
                                  • Zoho One Backup of entire account

                                    Hello, When using Zoho one is there a way to backup your entire account of all apps that you are using \ activively using in a single step or do you have to backup each applications data individually? Thanks,
                                  • ZIA in Zoho Cliq

                                    Is It possible to use the ZIA feature from Zoho Analytics in the Zoho Cliq?
                                  • Issue with “CC” and “Subject Details” of the initial mail when reply / replied all / forward using Zoho Mail Client (Desktop / Web Mail / Mobile App)

                                    It is observed that when I reply / reply all / forward a mail using Zoho Mail Client (Desktop / Web Mail / Mobile App), the “CC” and “Subject Details” are omitted from the mail which was replied/forwarded. However this is not the case with outlook mail
                                  • Unable to send Emails - 452 4.3.1 Temporary System Error

                                    Whene ever i request smtp server to send the email (without attachment). i recieve error "452 4.3.1 Temporary System Error"
                                  • I can't receive email

                                    I cannot receive any email sent to my Zoho email after the free upgrade plan trial is finished.
                                  • Help for the alisa adding

                                    Sorry, I would like to add a paypal alias on my domain email address. However, the system blocked it. How can I do it?
                                  • Problem with Writer and Workdrive

                                    Hi team, I’m the super admin for our Zoho One org. WorkDrive is active, and Zoho Docs is deprecated for our org. However, Zoho Writer cannot connect to WorkDrive at all — we’ve cleared cache, tried incognito, and restarted several times. I was able to
                                  • Lite plan attachment said 250mb but actually 25mb ?

                                    Lite plan attachment said 250mb but actually 25mb ? I can't attach over 25mb files, and can't receive mails has attached files over 25mb too
                                  • Zoho Books | Product updates | August 2025

                                    Hello users, We’ve rolled out new features and enhancements in Zoho Books. From the right sidebar where you can manage all your widgets, to integrating Zoho Payments feeds in Zoho Books, explore the updates designed to enhance your bookkeeping experience.
                                  • Closing Accounting Periods - Invoice/Posting dates

                                    Hi, I have seen in another thread but I'm unsure on how the 'transaction locking' works with regards to new and old transactions. When producing monthly accounts if I close December 24 accounts on 8th Jan 25 will transaction locking prevent me from posting
                                  • Constant color of a legend value

                                    It would be nice if we can set a constant color/pattern to a value when creating a chart. We would often use the same value in different graph options and I always have to copy the color that we've set to a certain value from a previous graph to make
                                  • Option to Customize Career Site URL Without “/jobs/Careers”

                                    Dear Zoho Recruit Team, I hope you are doing well. We would like to request an enhancement to the Career Site URL structure in Zoho Recruit. In the old version of the career site, our URL was simply: 👉 https://jobs.domain.com However, after moving to
                                  • Old vs New Value for Deleted Lookup Values

                                    Suppose the following scenario, where a value in a lookup is deleted: 1. User has countries form 2. Form A has a lookup to countries form 3. User selects Italy in Form A and saves it with the Italy ID 4. Form A report shows Italy 5. Italy is inadvertently
                                  • Next Page