How to migrate your V2 integration to V3 with minimal user impact.
Constant Contact partners and developers who have an existing V2 API integration will need to migrate their local user data to the V3 API format when building new V3 integrations.

Who Needs to Migrate Data

You will need to migrate your V2 API data if you have a V2 integration that stores Constant Contact data locally. This includes data such as contacts, email campaigns, lists, and reporting.

Why Do I Need Update My V2 Data

The V3 API uses Universally Unique Identifier (UUID) format for resource identifiers, while the V2 API uses sequence identifiers for resources. By adding the V3 identifiers to your local user data, you can use your local user data to make calls to the V3 API. Your users will be able to use their existing account data with the V3 version of your application with minimal, if any, disruption or action on their part.

How Do I Update V2 Data with V3 IDs

Use the V3 cross reference endpoints or the V2 collection endpoints to return the new V3 identifier for a resource.

The V3 API xref endpoints are intended as tools for migrating your existing local V2 user data to the V3 API format. The V3 API xref endpoints are not intended for regular and repeated use. Constant Contact will eventually deprecate and remove these endpoints.
Resource API Version Endpoint Description More Information
Contact V3 /contacts/contact_id_xrefs Use the contact_sequence_numbers query parameter to send in V2 contact id values, and get the V2 and V3 IDs in the response. See Contacts V3 Changes and Migration for more information.
V2 Contact Collection Use the
include_contact_id=true
query parameter to have the V3
contact_id
for each contact included in the response payload.
See Contacts V3 Changes and Migration for more information.
List V3 /contact_lists/list_id_xrefs Use the
list_sequence_numbers
query parameter to send in V2 list id values, and get the V2 and V3 IDs in the response.
See Lists V3 Changes and Migration for more information.
V2 List Collection Use the
include_list_id=true
query parameter to have the V3
list_id
property for each list included in the response payload.
See Lists V3 Changes and Migration for more information.
Emails V3 /emails/campaign_id_xrefs Use the
v2_email_campaign_ids
query parameter to send in V2 campaignId values, and get the corresponding V2 and V3 IDs in the response.
See Email Campaigns V3 Changes and Migration for more information.
V2 N/A N/A N/A