PHP SDK - Loops

Introduction

This is the official PHP package for Loops, an email platform for modern software companies.

Installation

Install the Loops package using Composer:

composer require loops-so/loops

Usage

You will need a Loops API key to use the package.

In your Loops account, go to the API Settings page and click Generate key.

Copy this key and save it in your application code (for example, in an environment variable).

See the API documentation to learn more about rate limiting and error handling.

To use the package, first initialise the client with your API key, then you can call one of the methods.

API rate limits can be handled with the included RateLimitExceededError exception.

use Loops\LoopsClient;

$loops = new LoopsClient(env('LOOPS_API_KEY'));

// Test API key
$result = $loops->apiKey->test();

// Create a contact and catch errors
try {
    $result = $loops->contacts->create('[email protected]', [
      'firstName' => 'John'
    ]);
} catch (Loops\Exceptions\APIError $e) {
    // Handle API errors (400, 401, 403, etc)
    echo $e->getMessage();
    $returnedJson = $e->getJson(); // JSON returned by the API
    $statusCode = $e->getStatusCode(); // HTTP status code from the response
} catch (\Exception $e) {
    // Handle any other unexpected errors
    echo "Unexpected error: " . $e->getMessage();
}

Handling rate limits

You can use the check for rate limit issues with your requests.

You can access details about the rate limits from the getLimit and getRemaining functions.

try {
    $result = $loops->contacts->create('[email protected]', [
      'firstName' => 'John'
    ]);
} catch (Loops\Exceptions\RateLimitExceededError $e) {
    // Handle rate limiting
    echo "Rate limit hit. Limit: " . $e->getLimit() . ", requests remaining: " . $e->getRemaining();
} catch (Loops\Exceptions\APIError $e) {
    // Handle API errors (400, 401, 403, etc)
    echo $e->getMessage();
} catch (\Exception $e) {
    // Handle any other unexpected errors
    echo "Unexpected error: " . $e->getMessage();
}

Default contact properties

Each contact in Loops has a set of default properties. These will always be returned in API results.

id
email
firstName
lastName
source
subscribed
userGroup
userId

Custom contact properties

You can use custom contact properties in API calls. Please make sure to add custom properties in your Loops account before using them with the SDK.

Methods

apiKey->test()

Test if your API key is valid.

API Reference

Parameters

None

Example

$result = $loops->apiKey->test();

Response

This method will return a success or error message:

{
  "success": true,
  "teamName": "Company name"
}

{
  "error": "Invalid API key"
}

contacts->create()

Create a new contact.

API Reference

Parameters

Name	Type	Required	Notes
`$email`	string	Yes	If a contact already exists with this email address, an `APIError` will be thrown.
`$properties`	array	No	An array containing default and any custom properties for your contact. Please add custom properties in your Loops account before using them with the SDK. Values can be of type `string`, `number`, `null` (to reset a value), `boolean` or `date` (see allowed date formats).
`$mailing_lists`	array	No	An array of mailing list IDs and boolean subscription statuses.

Examples

$result = $loops->contacts->create("[email protected]");

$contact_properties = [
  'firstName' => "Bob" /* Default property */,
  'favoriteColor' => "Red" /* Custom property */,
];
$mailing_lists = [
  'cm06f5v0e45nf0ml5754o9cix' => TRUE,
  'cm16k73gq014h0mmj5b6jdi9r' => FALSE,
];
$result = $loops->contacts->create(
  email: "[email protected]",
  properties: $contact_properties,
  mailing_lists: $mailing_lists
);

Response

{
  "success": true,
  "id": "id_of_contact"
}

Error handling is done through the APIError class, which provides getStatusCode() and getJson() methods for retrieving the API’s error response details. For implementation examples, see the Usage section.

// HTTP 400 Bad Request
{
  "success": false,
  "message": "An error message here."
}

contacts->update()

Update a contact.

Note: To update a contact’s email address, the contact requires a userId value. Then you can make a request with their userId and an updated email address.

API Reference

Parameters

Name	Type	Required	Notes
`$email`	string	Yes	The email address of the contact to update. If there is no contact with this email address, a new contact will be created using the email and properties in this request.
`$properties`	array	No	An array containing default and any custom properties for your contact. Please add custom properties in your Loops account before using them with the SDK. Values can be of type `string`, `number`, `null` (to reset a value), `boolean` or `date` (see allowed date formats).
`$mailing_lists`	array	No	An array of mailing list IDs and boolean subscription statuses.

Example

$contact_properties = [
  'firstName' => 'Bob', /* Default property */
  'favoriteColor' => 'Blue' /* Custom property */
];
$response = $loops->contacts->update(
  email: '[email protected]',
  properties: $contact_properties
);

// Updating a contact's email address using userId
$results = $loops->contacts->update(
  email: '[email protected]',
  properties: [
    'userId' => '1234'
  ]
);

Response

{
  "success": true,
  "id": "id_of_contact"
}

// HTTP 400 Bad Request
{
  "success": false,
  "message": "An error message here."
}

contacts->find()

Find a contact.

API Reference

Parameters

You must use one parameter in the request.

Name	Type	Required	Notes
`$email`	string	No
`$user_id`	string	No

Examples

$result = $loops->contacts->find(email: '[email protected]');

$result = $loops->contacts->find(user_id: '12345');

Response

This method will return a list containing a single contact object, which will include all default properties and any custom properties.

If no contact is found, an empty list will be returned.

[
  {
    "id": "cll6b3i8901a9jx0oyktl2m4u",
    "email": "[email protected]",
    "firstName": "Bob",
    "lastName": null,
    "source": "API",
    "subscribed": true,
    "userGroup": "",
    "userId": "12345",
    "mailingLists": {
      "cm06f5v0e45nf0ml5754o9cix": true
    },
    "favoriteColor": "Blue" /* Custom property */
  }
]

contacts->delete()

Delete a contact.

API Reference

Parameters

You must use one parameter in the request.

Name	Type	Required	Notes
`$email`	string	No
`$user_id`	string	No

Example

$result = $loops->contacts->delete(email: '[email protected]')

$result = $loops->contacts->delete(user_id: '12345')

Response

{
  "success": true,
  "message": "Contact deleted."
}

// HTTP 400 Bad Reuqest
{
  "success": false,
  "message": "An error message here."
}

// HTTP 404 Not Found
{
  "success": false,
  "message": "An error message here."
}

contactProperties->create()

Create a new contact property.

API Reference

Parameters

Name	Type	Required	Notes
`$name`	string	Yes	The name of the property. Should be in camelCase, like `planName` or `favouriteColor`.
`$type`	string	Yes	The property’s value type. Can be one of `string`, `number`, `boolean` or `date`.

Examples

$result = $loops->contactProperties->create("planName", "string");

Response

{
  "success": true
}

// HTTP 400 Bad Request
{
  "success": false,
  "message": "An error message here."
}

contactProperties->get()

Get a list of your account’s contact properties.

API Reference

Parameters

Name	Type	Required	Notes
`$list`	string	No	Use “custom” to retrieve only your account’s custom properties.

Example

$result = $loops->contactProperties->get();

$result = $loops->contactProperties->get(list: "custom");

Response

This method will return a list of contact property objects containing key, label and type attributes.

[
  {
    "key": "firstName",
    "label": "First Name",
    "type": "string"
  },
  {
    "key": "lastName",
    "label": "Last Name",
    "type": "string"
  },
  {
    "key": "email",
    "label": "Email",
    "type": "string"
  },
  {
    "key": "notes",
    "label": "Notes",
    "type": "string"
  },
  {
    "key": "source",
    "label": "Source",
    "type": "string"
  },
  {
    "key": "userGroup",
    "label": "User Group",
    "type": "string"
  },
  {
    "key": "userId",
    "label": "User Id",
    "type": "string"
  },
  {
    "key": "subscribed",
    "label": "Subscribed",
    "type": "boolean"
  },
  {
    "key": "createdAt",
    "label": "Created At",
    "type": "date"
  },
  {
    "key": "favoriteColor",
    "label": "Favorite Color",
    "type": "string"
  },
  {
    "key": "plan",
    "label": "Plan",
    "type": "string"
  }
]

mailingLists->get()

Get a list of your account’s mailing lists. Read more about mailing lists

API Reference

Parameters

None

Example

$result = $loops->mailingLists->get();

Response

This method will return a list of mailing list objects containing id, name, description and isPublic attributes.

If your account has no mailing lists, an empty list will be returned.

[
  {
    "id": "cm06f5v0e45nf0ml5754o9cix",
    "name": "Main list",
    "description": "All customers.",
    "isPublic": true
  },
  {
    "id": "cm16k73gq014h0mmj5b6jdi9r",
    "name": "Investors",
    "description": null,
    "isPublic": false
  }
]

events->send()

Send an event to trigger an email in Loops. Read more about events

API Reference

Parameters

Name	Type	Required	Notes
`$event_name`	string	Yes
`$email`	string	No	The contact’s email address. Required if `$user_id` is not present.
`$user_id`	string	No	The contact’s unique user ID. If you use `$user_id` without `$email`, this value must have already been added to your contact in Loops. Required if `$email` is not present.
`$contact_properties`	array	No	An array containing contact properties, which will be updated or added to the contact when the event is received. Please add custom properties in your Loops account before using them with the SDK. Values can be of type `string`, `number`, `null` (to reset a value), `boolean` or `date` (see allowed date formats).
`$event_properties`	array	No	An array containing event properties, which will be made available in emails that are triggered by this event. Values can be of type `string`, `number`, `boolean` or `date` (see allowed date formats).
`$mailing_lists`	array	No	An array of mailing list IDs and boolean subscription statuses.
`$headers`	array	No	Additional headers to send with the request.

Examples

$result = $loops->events->send(
  event_name: 'signup',
  email: '[email protected]'
);

$result = $loops->events->send(
  event_name: 'signup',
  email: '[email protected]',
  event_properties: [
    'username' => 'user1234',
    'signupDate' => '2024-03-21T10:09:23Z'
  ],
  mailing_lists: [
    'cm06f5v0e45nf0ml5754o9cix' => true,
    'cm16k73gq014h0mmj5b6jdi9r' => false
  ]
;

# In this case with both email and userId present, the system will look for a contact with either a
#  matching `email` or `user_id` value.
# If a contact is found for one of the values (e.g. `email`), the other value (e.g. `user_id`) will be updated.
# If a contact is not found, a new contact will be created using both `email` and `user_id` values.
# Any values added in `contact_properties` will also be updated on the contact.
$result = $loops->events->send(
  event_name: 'signup',
  email: '[email protected]',
  user_id: '1234567890',
  contact_properties: [
    'firstName' => 'Bob',
    'plan' => 'pro',
  }]
});

# Example with Idempotency-Key header
$result = $loops->events->send(
  event_name: 'signup',
  email: '[email protected]',
  headers: [
    'Idempotency-Key' => '550e8400-e29b-41d4-a716-446655440000'
  ]
);

Response

{
  "success": true
}

// HTTP 400 Bad Request
{
  "success": false,
  "message": "An error message here."
}

transactional->send()

Send a transactional email to a contact. Learn about sending transactional email

API Reference

Parameters

Name	Type	Required	Notes
`$transactional_id`	string	Yes	The ID of the transactional email to send.
`$email`	string	Yes	The email address of the recipient.
`$add_to_audience`	boolean	No	If `true`, a contact will be created in your audience using the `$email` value (if a matching contact doesn’t already exist).
`$data_variables`	array	No	An array containing data as defined by the data variables added to the transactional email template. Values can be of type `string` or `number`.
`$attachments`	array[]	No	A list of attachments objects. Please note: Attachments need to be enabled on your account before using them with the API. Read more
`$attachments[]["filename"]`	string	No	The name of the file, shown in email clients.
`$attachments[]["content_type"]`	string	No	The MIME type of the file.
`$attachments[]["data"]`	string	No	The base64-encoded content of the file.
`$headers`	array	No	Additional headers to send with the request.

Examples

$result = $loops->transactional->send(
  transactional_id: 'clfq6dinn000yl70fgwwyp82l',
  email: '[email protected]',
  data_variables: [
    'loginUrl' => 'https://myapp.com/login/',
  ]
);

# Example with Idempotency-Key header
$result = $loops->transactional->send(
  transactional_id: 'clfq6dinn000yl70fgwwyp82l',
  email: '[email protected]',
  data_variables: [
    'loginUrl' => 'https://myapp.com/login/',
  ],
  headers: [
    'Idempotency-Key' => '550e8400-e29b-41d4-a716-446655440000'
  ]
);

# Please contact us to enable attachments on your account.
$result = $loops->transactional->send(
  transactional_id: 'clfq6dinn000yl70fgwwyp82l',
  email: '[email protected]',
  data_variables: [
    'loginUrl' => 'https://myapp.com/login/',
  ],
  attachments: [
    [
      'filename' => 'presentation.pdf',
      'content_type' => 'application/pdf',
      'data' => base64_encode(file_get_contents('path/to/presentation.pdf'))
    ]
  ]
);

Response

{
  "success": true
}

If there is a problem with the request, a descriptive error message will be returned:

// HTTP 400 Bad Request
{
  "success": false,
  "path": "dataVariables",
  "message": "There are required fields for this email. You need to include a 'dataVariables' object with the required fields."
}

// HTTP 400 Bad Request
{
  "success": false,
  "error": {
    "path": "dataVariables",
    "message": "Missing required fields: login_url"
  },
  "transactionalId": "clfq6dinn000yl70fgwwyp82l"
}

transactional->get()

Get a list of published transactional emails.

API Reference

Parameters

Name	Type	Required	Notes
`$per_page`	integer	No	How many results to return per page. Must be between 10 and 50. Defaults to 20 if omitted.
`$cursor`	string	No	A cursor, to return a specific page of results. Cursors can be found from the `pagination.nextCursor` value in each response.

Example

$result = $loops->transactional->get();

$result = $loops->transactional->get(per_page: 15);

Response

{
  "pagination": {
    "totalResults": 23,
    "returnedResults": 20,
    "perPage": 20,
    "totalPages": 2,
    "nextCursor": "clyo0q4wo01p59fsecyxqsh38",
    "nextPage": "https://app.loops.so/api/v1/transactional?cursor=clyo0q4wo01p59fsecyxqsh38&perPage=20"
  },
  "data": [
    {
      "id": "clfn0k1yg001imo0fdeqg30i8",
      "lastUpdated": "2023-11-06T17:48:07.249Z",
      "dataVariables": []
    },
    {
      "id": "cll42l54f20i1la0lfooe3z12",
      "lastUpdated": "2025-02-02T02:56:28.845Z",
      "dataVariables": [
        "confirmationUrl"
      ]
    },
    {
      "id": "clw6rbuwp01rmeiyndm80155l",
      "lastUpdated": "2024-05-14T19:02:52.000Z",
      "dataVariables": [
        "firstName",
        "lastName",
        "inviteLink"
      ]
    },
    ...
  ]
}

Version history

v1.0.1 (May 22, 2025) - Added a headers argument in events-send() and transactional->send(), enabling support for the Idempotency-Key header.
v1.0.0 (May 6, 2025)
- Fixed client imports.
- Added test suite and some basic tests.
v0.1.0 (Feb 27, 2025) - Initial release.

Contributing

Bug reports and pull requests are welcome on GitHub at github.com/Loops-so/loops-rb. Please read our Contributing Guidelines.

Learn

API

Guides

​Introduction

​Installation

​Usage

​Handling rate limits

​Default contact properties

​Custom contact properties

​Methods

​apiKey->test()

​Parameters

​Example

​Response

​contacts->create()

​Parameters

​Examples

​Response

​contacts->update()

​Parameters

​Example

​Response

​contacts->find()

​Parameters

​Examples

​Response

​contacts->delete()

​Parameters

​Example

​Response

​contactProperties->create()

​Parameters

​Examples

​Response

​contactProperties->get()

​Parameters

​Example

​Response

​mailingLists->get()

​Parameters

​Example

​Response

​events->send()

​Parameters

​Examples

​Response

​transactional->send()

​Parameters

​Examples

​Response

​transactional->get()

​Parameters

​Example

​Response

​Version history

​Contributing

Introduction

Installation

Usage

Handling rate limits

Default contact properties

Custom contact properties

Methods

apiKey->test()

Parameters

Example

Response

contacts->create()

Parameters

Examples

Response

contacts->update()

Parameters

Example

Response

contacts->find()

Parameters

Examples

Response

contacts->delete()

Parameters

Example

Response

contactProperties->create()

Parameters

Examples

Response

contactProperties->get()

Parameters

Example

Response

mailingLists->get()

Parameters

Example

Response

events->send()

Parameters

Examples

Response

transactional->send()

Parameters

Examples

Response

transactional->get()

Parameters

Example

Response

Version history

Contributing