The Toweringmedia Constant Contact Extension connects Magento 2 customers and newsletter subscribers with Constant Contact through secure, bidirectional synchronization. It uses OAuth 2.0, queue-based outbound processing, scheduled inbound polling, and configurable conflict resolution to keep subscription data synchronized reliably without slowing Magento operations.

Product Name: Toweringmedia Constant Contact Extension for Magento 2

Support & Updates: 12 months included

• Bidirectional synchronization between Magento customers, newsletter subscribers, and Constant Contact
• Secure Constant Contact API v3 integration using OAuth 2.0
• Database-backed queue for reliable outbound synchronization
• Scheduled inbound contact polling with synchronization checkpoints
• Magento Wins, Constant Contact Wins, and Newest Wins conflict-resolution options
• Automatic retry with exponential backoff for temporary API failures
• Loop prevention and idempotent processing to reduce duplicate synchronization
• Encrypted storage of OAuth access and refresh tokens
• Magento Admin controls for connecting, disconnecting, testing, and monitoring synchronization
• Manual synchronization and dry-run testing through Magento CLI commands

Please refer to the installation guide in the following article: https://toweringmedia.com/installation

Before configuring the extension, ensure the following requirements are available:

• A supported Magento 2 installation
• An active Constant Contact account
• A Constant Contact developer application with an API Key and Client Secret
• The exact Magento OAuth callback URL registered in the Constant Contact developer portal
• HTTPS enabled for the Magento Admin URL
• Magento cron configured and running correctly
• Constant Contact list membership IDs for synchronization
• Magento Admin access for extension configuration
• Outbound server access to the Constant Contact API endpoints

After installing and enabling the extension, go to:

Magento Admin > Stores > Configuration > Customers > Constant Contact (Towering Media)

• Enable or disable the Constant Contact integration.
• Enable the required outbound and inbound synchronization options.
• Select the appropriate website or store-view scope before saving configuration values.

Enter the credentials generated from your Constant Contact developer application:

• API Key / Client ID
• Client Secret
• Redirect URI Override - leave empty to use the automatically generated Magento callback URL, or enter the exact registered callback URL when required.

The default callback URL follows this format:

https://your-domain.com/{admin_path}/constantcontact/oauth/callback

The callback URL configured in Magento must exactly match the URL registered in the Constant Contact developer portal.

After saving the OAuth credentials:

1. Click Connect.
2. Sign in to the required Constant Contact account.
3. Approve the requested permissions.
4. Constant Contact redirects back to Magento Admin.
5. Confirm that the connection status shows as connected.

Access and refresh tokens are stored using Magento's encryption service.

Configure the following synchronization options:

• Magento customer synchronization
• Magento newsletter-subscriber synchronization
• Outbound queue processing
• Scheduled inbound contact polling
• Constant Contact list membership IDs
• Synchronization batch or processing settings, where available

Select how subscription conflicts between Magento and Constant Contact should be handled:

• Magento Wins - Magento is treated as the preferred source.
• Constant Contact Wins - Constant Contact membership is treated as the preferred source.
• Newest Wins - The most recently updated state is used.

Choose this setting carefully according to the store's subscription-management workflow.

Click API Smoke Test to confirm that:

• OAuth authentication is valid.
• Magento can communicate with Constant Contact API v3.
• The configured account and tokens are working.

Use Disconnect when you need to remove the current Constant Contact authorization. After disconnecting, automatic synchronization cannot continue until the account is connected again.

After the Constant Contact account is connected and synchronization settings are saved, the extension works automatically through Magento observers, the synchronization queue, and scheduled cron jobs.

• A Magento customer or newsletter-subscriber record is created or updated.
• The extension adds a synchronization request to its database-backed outbound queue.
• Magento cron or the synchronization CLI processes the queued request and sends the update to Constant Contact.
• The scheduled inbound process retrieves Constant Contact contact membership changes using synchronization checkpoints.
• Magento applies the configured conflict-resolution rule and records the result in the synchronization logs.

• Synchronization is asynchronous. Changes may not appear in Constant Contact or Magento immediately because they are processed by cron.
• Reliable Magento cron execution is required for automatic outbound queue processing and inbound polling.
• Temporary API failures and rate-limit responses are retried automatically using exponential backoff.
• Permanent errors are marked as failed and remain available for administrative review.
• Idempotent processing and synchronization hashes help prevent duplicate work and update loops.
• The selected conflict-resolution mode determines which subscription state is kept when Magento and Constant Contact disagree.
• Initial processing or large contact lists may take longer and may require batch-size or cron-frequency adjustments.

Use the read-only synchronization queue and log grids in Magento Admin to review pending, processing, retry, completed, or failed operations. If a change has not synchronized, first confirm that cron is running, the OAuth connection is active, and the configured Constant Contact list membership IDs are correct.

Administrators can use the Magento CLI synchronization command for controlled manual processing. Dry-run mode can be used to validate the synchronization flow without applying live changes.

php bin/magento toweringmedia:constantcontact:sync --dry-run

• Inbound synchronization primarily reconciles Magento newsletter subscription status. Customer information is updated only where supported and linked by the integration.
• The extension uses scheduled polling rather than Constant Contact webhooks.
• Campaign sending, journeys, ecommerce catalog synchronization, and storefront signup widgets are not included.
• Disconnecting the Constant Contact account stops synchronization until the account is authorized again.

After configuration, complete these checks before relying on automatic synchronization:

• Confirm that the Toweringmedia_ConstantContact module is enabled.
• Confirm that the extension settings are saved under the intended website or store scope.
• Verify that the OAuth callback URL exactly matches the URL configured in the Constant Contact developer application.
• Confirm that Magento Admin shows the Constant Contact account as connected.
• Run API Smoke Test and confirm that it completes successfully.
• Confirm that Magento cron is installed and running reliably.
• Test outbound synchronization by updating a Magento customer or newsletter subscriber, then verify that the queue item is processed and the Constant Contact list membership is updated.
• Test inbound synchronization by changing a contact's Constant Contact list membership, then verify that Magento reconciles the newsletter subscription status after the next polling cycle.
• Verify that the selected conflict-resolution mode produces the expected result when Magento and Constant Contact contain different subscription states.
• Review the synchronization queue and log grids for unexpected failures or a growing retry backlog.
• Run php bin/magento toweringmedia:constantcontact:sync –dry-run and confirm that it completes without unexpected errors.
• Confirm that application logs do not expose OAuth access tokens, refresh tokens, or the Client Secret.

Use the following checks when synchronization or authorization does not work as expected.

• Confirm that the API Key / Client ID and Client Secret are correct.
• Verify that the callback URL in Magento exactly matches the redirect URI registered in the Constant Contact developer application, including the protocol, domain, and Magento Admin path.
• Confirm that the Magento Admin URL uses HTTPS, save the configuration, and try Connect again.

• Confirm that the account still shows as connected and that the configured Constant Contact account is active.
• Disconnect and reconnect the account if the authorization has expired or been revoked.
• Confirm that the Magento server can make outbound HTTPS requests to Constant Contact API endpoints.

• Confirm that customer or newsletter-subscriber synchronization is enabled for the correct configuration scope.
• Verify that Magento cron is running and processing the outbound queue.
• Review the synchronization queue and logs for pending, retry, or failed items.
• Run php bin/magento toweringmedia:constantcontact:sync –dry-run to check the synchronization flow without applying live changes.

• Confirm that inbound synchronization is enabled and that the correct Constant Contact list membership IDs are configured.
• Allow time for the next scheduled polling cycle; inbound changes are not received through webhooks.
• Confirm that cron is running and review the synchronization logs for polling or checkpoint errors.
• Remember that inbound synchronization primarily reconciles newsletter subscription status; customer data is updated only where supported and linked.

• Temporary rate-limit and server errors are retried automatically with exponential backoff, so processing may be delayed during an API outage.
• Permanent API errors are marked as failed. Review the logged error, correct invalid configuration or contact data, and process the synchronization again.
• If the retry backlog continues to grow, confirm API availability, OAuth status, cron frequency, and processing settings.

• Review the selected Magento Wins, Constant Contact Wins, or Newest Wins conflict-resolution mode.
• Confirm which system should be the preferred source for subscription changes, then save the appropriate mode at the correct configuration scope.
• Review synchronization timestamps and logs to determine which update was applied.

• Record the Magento version, extension version, affected store or website scope, and approximate time of the issue.
• Include the relevant queue status and sanitized synchronization-log message.
• Never share OAuth access tokens, refresh tokens, authorization codes, or the Client Secret in screenshots or support messages.

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