loops-python-unofficial 0.1.0

Unofficial Python SDK for Loops (loops.so) with sync and async clients

Unofficial Loops Python SDK

Introduction

Python SDK for Loops, with both sync and async clients. Mirrors the public JS SDK where it makes sense.

Installation

pip install loops-python-unofficial

You will need a Loops API key from your account settings.

Quick start

Sync

from loops_unofficial import LoopsClient, APIError, RateLimitExceededError

client = LoopsClient("<YOUR_API_KEY>")

try:
    resp = client.create_contact("[e-mail]")
except RateLimitExceededError as e:
    print(f"Rate limit exceeded ({e.limit}/s), remaining={e.remaining}")
except APIError as e:
    print(e.status_code, e.json)

Handling rate limits

If you import RateLimitExceededError you can check for rate limit issues with your requests.

You can access details about the rate limits from the limit and remaining attributes.

Async

import asyncio
from loops_unofficial import AsyncLoopsClient

async def main():
    client = AsyncLoopsClient("<YOUR_API_KEY>")
    try:
        resp = await client.create_contact("[e-mail]")
    finally:
        await client.aclose()

asyncio.run(main())

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

• test_api_key()
• create_contact(email, properties=None, mailing_lists=None)
• update_contact(email, properties, mailing_lists=None)
• find_contact(email=None, user_id=None)
• delete_contact(email=None, user_id=None)
• createcontact_property(name, type)
• getcontact_properties(list=None)
• get_mailing_lists()
• send_event(email=None, user_id=None, event_name=..., contact_properties=None, event_properties=None, mailing_lists=None, headers=None)
• send_transactional_email(transactional_id, email, add_to_audience=None, data_variables=None, attachments=None, headers=None)
• get_transactional_emails(per_page=None, cursor=None)

---

testApiKey()

Test that an API key is valid.

API Reference

Parameters

None

Example (Python)

from loops_unofficial import LoopsClient

client = LoopsClient("<API_KEY>")
resp = client.test_api_key()

Response

{
  "success": true,
  "teamName": "My team"
}

Error handling is done through the APIError class, which provides statusCode and json properties containing the API's error response details. For implementation examples, see the Usage section.

HTTP 401 Unauthorized
{
  "error": "Invalid API key"
}

---

createContact()

Create a new contact.

API Reference

Parameters

Name	Type	Required	Notes
email	string	Yes	If a contact already exists with this email address, an error response will be returned.
properties	object	No	An object 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).
mailingLists	object	No	An object of mailing list IDs and boolean subscription statuses.

Examples (Python)

from loops_unofficial import LoopsClient

client = LoopsClient("<API_KEY>")

# Minimal
resp = client.create_contact("[e-mail]")

# With properties and mailing lists
contact_properties = {"firstName": "Bob", "favoriteColor": "Red"}
mailing_lists = {"cm06f5v0e45nf0ml5754o9cix": True, "cm16k73gq014h0mmj5b6jdi9r": False}
resp = client.create_contact("[e-mail]", contact_properties, mailing_lists)

Response

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

Error handling is done through the APIError class, which provides statusCode and json properties containing the API's error response details. For implementation examples, see the Usage section.

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

---

updateContact()

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	object	No	An object 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).
mailingLists	object	No	An object of mailing list IDs and boolean subscription statuses.

Example (Python)

client.update_contact("[e-mail]", {"firstName": "Bob", "favoriteColor": "Blue"})

# Updating a contact's email address using userId
client.update_contact("[e-mail]", {"userId": "1234"})

Response

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

Error handling is done through the APIError class, which provides statusCode and json properties containing the API's error response details. For implementation examples, see the Usage section.

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

---

findContact()

Find a contact.

API Reference

Parameters

You must use one parameter in the request.

Name	Type	Required	Notes
email	string	No
userId	string	No

Examples (Python)

client.find_contact(email="[e-mail]")
client.find_contact(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": "[e-mail]",
    "firstName": "Bob",
    "lastName": null,
    "source": "API",
    "subscribed": true,
    "userGroup": "",
    "userId": "12345",
    "mailingLists": {
      "cm06f5v0e45nf0ml5754o9cix": true
    },
    "favoriteColor": "Blue" /* Custom property */
  }
]

---

deleteContact()

Delete a contact, either by email address or userId.

API Reference

Parameters

You must use one parameter in the request.

Name	Type	Required	Notes
email	string	No
userId	string	No

Example (Python)

client.delete_contact(email="[e-mail]")
client.delete_contact(user_id="12345")

Response

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

Error handling is done through the APIError class, which provides statusCode and json properties containing the API's error response details. For implementation examples, see the Usage section.

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

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

---

createContactProperty()

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 (Python)

client.create_contact_property("planName", "string")

Response

{
  "success": true
}

Error handling is done through the APIError class, which provides statusCode and json properties containing the API's error response details. For implementation examples, see the Usage section.

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

---

getContactProperties()

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 (Python)

client.get_contact_properties()
client.get_contact_properties("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"
  }
]

---

getMailingLists()

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

API Reference

Parameters

None

Example (Python)

client.get_mailing_lists()

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
  }
]

---

sendEvent()

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

API Reference

Parameters

Name	Type	Required	Notes
email	string	No	The contact's email address. Required if userId is not present.
userId	string	No	The contact's unique user ID. If you use userId without email, this value must have already been added to your contact in Loops. Required if email is not present.
eventName	string	Yes
contactProperties	object	No	An object 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).
eventProperties	object	No	An object 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).
mailingLists	object	No	An object of mailing list IDs and boolean subscription statuses.
headers	object	No	Additional headers to send with the request.

Examples (Python)

# Minimal
client.send_event(email="[e-mail]", event_name="signup")

# With event properties and mailing lists
client.send_event(
    email="[e-mail]",
    event_name="signup",
    event_properties={"username": "user1234", "signupDate": "2024-03-21T10:09:23Z"},
    mailing_lists={"cm06f5v0e45nf0ml5754o9cix": True, "cm16k73gq014h0mmj5b6jdi9r": False},
)

# With both email and userId and contact properties
client.send_event(
    user_id="1234567890",
    email="[e-mail]",
    event_name="signup",
    contact_properties={"firstName": "Bob", "plan": "pro"},
)

# With Idempotency-Key header
client.send_event(
    email="[e-mail]",
    event_name="signup",
    headers={"Idempotency-Key": "550e8400-e29b-41d4-a716-446655440000"},
)

Response

{
  "success": true
}

Error handling is done through the APIError class, which provides statusCode and json properties containing the API's error response details. For implementation examples, see the Usage section.

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

---

sendTransactionalEmail()

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

API Reference

Parameters

Name	Type	Required	Notes
transactionalId	string	Yes	The ID of the transactional email to send.
email	string	Yes	The email address of the recipient.
addToAudience	boolean	No	If true, a contact will be created in your audience using the email value (if a matching contact doesn’t already exist).
dataVariables	object	No	An object containing data as defined by the data variables added to the transactional email template. Values can be of type string or number.
attachments	object[]	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[].contentType	string	No	The MIME type of the file.
attachments[].data	string	No	The base64-encoded content of the file.
headers	object	No	Additional headers to send with the request.

Examples (Python)

# Minimal
client.send_transactional_email(
    transactional_id="clfq6dinn000yl70fgwwyp82l",
    email="[e-mail]",
    data_variables={"loginUrl": "https://myapp.com/login/"},
)

# With Idempotency-Key header
client.send_transactional_email(
    transactional_id="clfq6dinn000yl70fgwwyp82l",
    email="[e-mail]",
    data_variables={"loginUrl": "https://myapp.com/login/"},
    headers={"Idempotency-Key": "550e8400-e29b-41d4-a716-446655440000"},
)

# With attachments (requires attachments to be enabled on your account)
client.send_transactional_email(
    transactional_id="clfq6dinn000yl70fgwwyp82l",
    email="[e-mail]",
    data_variables={"loginUrl": "https://myapp.com/login/"},
    attachments=[
        {
            "filename": "presentation.pdf",
            "contentType": "application/pdf",
            "data": "JVBERi0xLjMKJcTl8uXrp/Og0MTGCjQgMCBvYmoKPD...",
        }
    ],
)

Response

{
  "success": true
}

Error handling is done through the APIError class, which provides statusCode and json properties containing the API's error response details. For implementation examples, see the Usage section.

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"
}

---

getTransactionalEmails()

Get a list of published transactional emails.

API Reference

Parameters

Name	Type	Required	Notes
perPage	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 (Python)

client.get_transactional_emails()
client.get_transactional_emails(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

• v5.0.1 (May 13, 2025) - Added a headers parameter for sendEvent() and sendTransactionalEmail(), enabling support for the Idempotency-Key header.
• v5.0.0 (Apr 29, 2025)
  • Types are now exported so you can use them in your application.
  • ValidationError is now thrown when parameters are not added correctly.
  • Error is now returned if the API key is missing.
  • Added tests.
• v4.1.0 (Feb 27, 2025) - Support for new List transactional emails endpoint.
• v4.0.0 (Jan 16, 2025)
  • Added APIError to more easily understand API errors. See usage example.
  • Added support for two new contact property endpoints: List contact properties and Create contact property.
  • Deprecated and removed the getCustomFields() method (you can now use listContactProperties() instead).
• v3.4.1 (Dec 18, 2024) - Support for a new description attribute in getMailingLists().
• v3.4.0 (Oct 29, 2024) - Added rate limit handling with RateLimitExceededError.
• v3.3.0 (Sep 9, 2024) - Added testApiKey() method.
• v3.2.0 (Aug 23, 2024) - Added support for a new mailingLists attribute in findContact().
• v3.1.1 (Aug 16, 2024) - Support for a new isPublic attribute in getMailingLists().
• v3.1.0 (Aug 12, 2024) - The SDK now accepts null as a value for contact properties in createContact(), updateContact() and sendEvent(), which allows you to reset/empty properties.
• v3.0.0 (Jul 2, 2024) - sendTransactionalEmail() now accepts an object instead of separate parameters (breaking change).
• v2.2.0 (Jul 2, 2024) - Deprecated. Added new addToAudience option to sendTransactionalEmail().
• v2.1.1 (Jun 20, 2024) - Added support for mailing lists in createContact(), updateContact() and sendEvent().
• v2.1.0 (Jun 19, 2024) - Added support for new List mailing lists endpoint.
• v2.0.0 (Apr 19, 2024)
  • Added userId as a parameter to findContact(). This includes a breaking change for the findContact() parameters.
  • userId values must now be strings (could have also been numbers previously).
• v1.0.1 (Apr 1, 2024) - Fixed types for sendEvent().
• v1.0.0 (Mar 28, 2024) - Fix for ESM types. Switched to named export.
• v0.4.0 (Mar 22, 2024) - Support for new eventProperties in sendEvent(). This includes a breaking change for the sendEvent() parameters.
• v0.3.0 (Feb 22, 2024) - Updated minimum Node version to 18.0.0.
• v0.2.1 (Feb 6, 2024) - Fix for ESM imports.
• v0.2.0 (Feb 1, 2024) - CommonJS support.
• v0.1.5 (Jan 25, 2024) - getCustomFields() now returns type values for each contact property.
• v0.1.4 (Jan 25, 2024) - Added support for userId in sendEvent() request. Added missing error response type for sendEvent() requests.
• v0.1.3 (Dec 8, 2023) - Added support for transactional attachments.
• v0.1.2 (Dec 6, 2023) - Improved transactional error types.
• v0.1.1 (Nov 1, 2023) - Initial release.

---

Development

This project uses uv.

uv sync
uv run pytest
uv run ruff check
uv run mypy .

Publishing

Use GitHub Actions with PyPI Trusted Publishing.

Workflow:

• Tag a release locally: git tag v0.2.0 && git push --tags.
• The workflow .github/workflows/release.yml builds and publishes to PyPI on tag push using PyPA’s official action.
• To publish to TestPyPI manually, trigger the workflow (Run workflow) and choose testpypi.

Installing from TestPyPI

If you published to TestPyPI, install with an explicit index URL:

pip install --index-url https://test.pypi.org/simple/ \
            --extra-index-url https://pypi.org/simple \
            loops-python-unofficial

Releasing

1. Update version in pyproject.toml.
2. Create a tag: git tag vX.Y.Z && git push --tags.
3. Workflow builds with uv build and publishes via trusted publishing.
4. Alternatively dispatch the workflow and select testpypi to publish to TestPyPI.

---

Contributing

Bug reports and pull requests are welcome. Please read our Contributing Guidelines.