Integrating custom code with Mailchimp's API for group management involves several steps including understanding Mailchimp's terminology, working with the API endpoints for managing lists, interests (groups), and members, and using proper authentication mechanisms. Below is a comprehensive guide covering the entire process you need to integrate custom code with Mailchimp's API to manage subscriber groups effectively.
Understanding Mailchimp Groups and Interests
In Mailchimp's API, subscriber groups are referred to as "interests" under "interest categories." Each list (audience) can have multiple interest categories, and each category can have multiple interests (groups). These interests allow you to segment your audience and manage subscribers according to their preferences or any other criteria.
Getting Started: Authentication and Setup
1. Generate Mailchimp API Key:**
- Log in to your Mailchimp account.
- Navigate to your profile, then to "Extras" > "API keys."
- Create a new API key or use an existing one. This key is used to authenticate API requests.
2. Identify Your Data Center and Audience ID (List ID):**
- Your data center is the prefix in your API base URL (e.g., us19 in `https://us19.api.mailchimp.com`).
- Find your audience ID in the Mailchimp dashboard under Audience > Settings > Audience name and defaults, or via API.
3. Set Up API Headers:**
- Use basic authentication where the username can be anything (often "anystring") and the password is your API key.
- Set âContent-Type' to âapplication/json' for request payloads.
Managing Groups Using Mailchimp API Endpoints
Mailchimp groups (interests) are managed through specific endpoints under the list resource.
1. Working with Interest Categories
- List Interest Categories:**
- Endpoint: `GET /lists/{list_id}/interest-categories`
- Use this to retrieve all interest categories (group categories) associated with your list.
- Create an Interest Category:**
- Endpoint: `POST /lists/{list_id}/interest-categories`
- Payload example:
json
{
"title": "Preferred Products",
"type": "checkboxes"
}
- Type can be checkboxes, dropdown, or radio buttons.
- Get Specific Interest Category:**
- Endpoint: `GET /lists/{list_id}/interest-categories/{interest_category_id}`
- Update Interest Category:**
- Endpoint: `PATCH /lists/{list_id}/interest-categories/{interest_category_id}`
- You may update the title or type.
- Delete Interest Category:**
- Endpoint: `DELETE /lists/{list_id}/interest-categories/{interest_category_id}`
2. Managing Interests (Groups) Within a Category
- List Interests within a Category:**
- Endpoint: `GET /lists/{list_id}/interest-categories/{interest_category_id}/interests`
- Create a New Interest (Group):**
- Endpoint: `POST /lists/{list_id}/interest-categories/{interest_category_id}/interests`
- Payload example:
json
{
"name": "New Product Fanatics"
}
- Get Specific Interest:**
- Endpoint: `GET /lists/{list_id}/interest-categories/{interest_category_id}/interests/{interest_id}`
- Update Interest:**
- Endpoint: `PATCH /lists/{list_id}/interest-categories/{interest_category_id}/interests/{interest_id}`
- You can update the interest name or its enabled status.
- Delete Interest:**
- Endpoint: `DELETE /lists/{list_id}/interest-categories/{interest_category_id}/interests/{interest_id}`
Assigning Members to Groups (Interests)
When adding or updating members via the Mailchimp API, you specify the interests object to subscribe or unsubscribe them to groups.
Steps to Assign Subscriber to Groups
1. Add or Update a Member:**
- Endpoint: `PUT /lists/{list_id}/members/{subscriber_hash}`
- Use PUT to create or update a subscriber.
2. Subscriber Hash:**
- The subscriber hash is the MD5 hash of the lowercase version of the member's email address.
- Example in PHP: `md5(strtolower($email))`
3. Payload Structure:**
To assign interests, include an `interests` object where keys are interest IDs and values are boolean (true or false).
Example payload:
json
{
"email_address": "
<script language='JavaScript' type='text/javascript'>
<!--
var prefix = 'mailto:';
var suffix = '';
var attribs = '';
var path = 'hr' + 'ef' + '=';
var addy70302 = 'user' + '@';
addy70302 = addy70302 + 'example' + '.' + 'com';
document.write( '<a ' + path + '\'' + prefix + addy70302 + suffix + '\'' + attribs + '>' );
document.write( addy70302 );
document.write( '<\/a>' );
//-->
</script><script language='JavaScript' type='text/javascript'>
<!--
document.write( '<span style=\'display: none;\'>' );
//-->
</script>This e-mail address is being protected from spambots. You need JavaScript enabled to view it
<script language='JavaScript' type='text/javascript'>
<!--
document.write( '</' );
document.write( 'span>' );
//-->
</script>",
"status": "subscribed",
"interests": {
"interest_id_1": true,
"interest_id_2": false
},
"merge_fields": {
"FNAME": "John",
"LNAME": "Doe"
}
}
4. Making the API Request:**
- The request should be authenticated using the API key.
- Include necessary headers such as `Content-Type: application/json`.
Example PHP Code to Add/Update a Subscriber with Group Preferences
php
$apiKey = 'YOUR_API_KEY';
$listId = 'YOUR_LIST_ID';
$dc = substr($apiKey,strpos($apiKey,'-')+1); // Data center from API key
$email = '
<script language='JavaScript' type='text/javascript'>
<!--
var prefix = 'mailto:';
var suffix = '';
var attribs = '';
var path = 'hr' + 'ef' + '=';
var addy63798 = 'user' + '@';
addy63798 = addy63798 + 'example' + '.' + 'com';
document.write( '<a ' + path + '\'' + prefix + addy63798 + suffix + '\'' + attribs + '>' );
document.write( addy63798 );
document.write( '<\/a>' );
//-->
</script><script language='JavaScript' type='text/javascript'>
<!--
document.write( '<span style=\'display: none;\'>' );
//-->
</script>This e-mail address is being protected from spambots. You need JavaScript enabled to view it
<script language='JavaScript' type='text/javascript'>
<!--
document.write( '</' );
document.write( 'span>' );
//-->
</script>';
$subscriberHash = md5(strtolower($email));
$url = "https://{$dc}.api.mailchimp.com/3.0/lists/{$listId}/members/{$subscriberHash}";
$memberData = [
'email_address' => $email,
'status_if_new' => 'subscribed',
'status' => 'subscribed',
'interests' => [
'interest_id_1' => true,
'interest_id_2' => false
],
'merge_fields' => [
'FNAME' => 'John',
'LNAME' => 'Doe'
]
];
$jsonData = json_encode($memberData);
$ch = curl_init($url);
curl_setopt($ch, CURLOPT_USERPWD, "anystring:$apiKey");
curl_setopt($ch, CURLOPT_HTTPHEADER, ['Content-Type: application/json']);
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "PUT");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, $jsonData);
$response = curl_exec($ch);
curl_close($ch);
echo $response;
This code adds or updates a subscriber with membership to specified interest groups.
Retrieving Group IDs
Since interest IDs are needed to assign members to groups, you must fetch these IDs if you do not have them stored:
- Use `GET /lists/{list_id}/interest-categories` to list categories.
- Choose the relevant category and use `GET /lists/{list_id}/interest-categories/{interest_category_id}/interests` to get interests with their IDs.
- Store these for future use or dynamically retrieve them as needed.
Handling Segments and Tags for Advanced Grouping
Mailchimp also allows segmentation and tagging as another way to group subscribers:
- Segments: Saved filters based on subscriber data.
- Tags: Labels to organize contacts.
Segments and tags are managed through different API endpoints and can complement group management.
Error Handling and Best Practices
- Check for HTTP status codes in API responses. Success codes are 200 (OK), 201 (Created), or 204 (No Content).
- Handle error codes such as 400 (Bad Request), 401 (Unauthorized), and 429 (Rate Limit Exceeded).
- Implement retry logic especially for rate limits with exponential backoff.
- Secure your API key; do not expose it in client-side code.
- Use batch operations for bulk membership updates to improve efficiency.
Summary of Key Points for Integration
- Authenticate using your Mailchimp API key.
- Use the appropriate API endpoints to manage interest categories and interests (groups).
- Assign subscribers to groups by updating their "interests" object with interest IDs.
- Use subscriber email hashed in lowercase as the member identifier in the API.
- Manage groups dynamically by first fetching interest categories and interest IDs.
- Handle errors and rate limits to ensure robust integration.
- Consider using segments and tags for more granular audience management.