MailerLite

Connect & Ingest data from MailerLite

MailerLite is an email marketing platform that helps businesses create newsletters, landing pages, and automations to grow their audience. The Sling MailerLite connector extracts data from the MailerLite API v2, supporting subscribers, campaigns, groups, automations, segments, forms, custom fields, and webhooks.

CLI Pro Required: APIs require a CLI Pro token or Platform Plan.

Setup

The following credentials and inputs are accepted:

Secrets:

• api_token (required) -> Your MailerLite API token

Inputs:

• anchor_date (optional) -> Start date for initial data fetch (ISO 8601 format, e.g., 2024-01-01T00:00:00Z). Defaults to 1 year ago.

Getting Your API Token

1. Log in to your MailerLite dashboard

2. Navigate to Integrations from the left sidebar

3. Click Use on the MailerLite API section

4. Click Generate new token, give it a name (e.g., sling-data)

5. Accept the terms and click Create token

6. Copy the generated API token immediately (it won't be shown again)

Using sling conns

sling conns set MAILERLITE type=api spec=mailerlite secrets='{ api_token: "your_api_token_here" }'

Environment Variable

See here to learn more about the .env.sling file.

export MAILERLITE='{ type: api, spec: mailerlite, secrets: { api_token: "your_api_token_here" } }'

Sling Env File YAML

See here to learn more about the sling env.yaml file.

connections:
  MAILERLITE:
    type: api
    spec: mailerlite
    secrets:
      api_token: "your_api_token_here"

Replication

Here's an example replication configuration to sync MailerLite data to a PostgreSQL database:

source: MAILERLITE
target: MY_POSTGRES

defaults:
  mode: full-refresh
  object: mailerlite.{stream_name}

streams:
  # Core subscriber data
  subscribers:
    mode: incremental
    primary_key: [id]
    update_key: updated_at
  groups:
  group_subscribers:

  # Campaign data
  campaigns:
    mode: incremental
    primary_key: [id]
    update_key: updated_at

  # Automations and segments
  automations:
  segments:

  # Forms
  forms_popup:
  forms_embedded:
  forms_promotion:

  # Reference data
  fields:
  webhooks:
  timezones:

Incremental sync example:

source: MAILERLITE
target: MY_POSTGRES

defaults:
  mode: incremental
  object: mailerlite.{stream_name}

streams:
  subscribers:
    primary_key: [id]
    update_key: updated_at
  campaigns:
    primary_key: [id]
    update_key: updated_at

Full refresh example:

source: MAILERLITE
target: MY_POSTGRES

defaults:
  mode: full-refresh
  object: mailerlite.{stream_name}

streams:
  groups:
  fields:
  timezones:
  automations:
  segments:

Endpoints

Subscribers

Endpoint	Description	Incremental
subscribers	All subscribers	Yes
groups	Subscriber groups	No
group_subscribers	Subscribers in each group (child of groups)	No

Campaigns

Endpoint	Description	Incremental
campaigns	All campaigns	Yes

Automation & Segmentation

Endpoint	Description	Incremental
automations	Automation workflows	No
segments	Subscriber segments	No

Forms

Endpoint	Description	Incremental
forms_popup	Popup forms	No
forms_embedded	Embedded forms	No
forms_promotion	Promotion forms	No

Reference Data

Endpoint	Description	Incremental
fields	Custom subscriber fields	No
webhooks	Configured webhooks	No
timezones	Available timezones	No

To discover available endpoints:

sling conns discover MAILERLITE

Parent-Child Endpoints

The group_subscribers endpoint is a child of the groups endpoint and requires groups to run first. It iterates through each group to fetch its subscribers.

Incremental Sync

The MailerLite connector supports time-based incremental sync for the following endpoints:

• subscribers - Syncs new/modified subscribers by updated_at

• campaigns - Syncs new/modified campaigns by updated_at

How it works

• First run: Fetches all records from the anchor date (defaults to 1 year ago)

• Subsequent runs: Only fetches records created or modified after the last sync timestamp

• Anchor date: You can customize the initial lookback period by setting the anchor_date input

Rate Limiting

The MailerLite API has a rate limit of 120 requests per minute.

The connector automatically:

• Uses conservative rate limiting (2 requests/second)

• Limits concurrency to 3 parallel requests

• Retries with exponential backoff on 429 (rate limit) responses

Common Use Cases

Sync Subscriber and Group Data

source: MAILERLITE
target: MY_POSTGRES

defaults:
  mode: full-refresh
  object: subscribers.{stream_name}

streams:
  subscribers:
    mode: incremental
    primary_key: [id]
    update_key: updated_at
  groups:
  group_subscribers:
  fields:

Sync Campaign Analytics

source: MAILERLITE
target: MY_POSTGRES

defaults:
  mode: full-refresh
  object: campaigns.{stream_name}

streams:
  campaigns:
    mode: incremental
    primary_key: [id]
    update_key: updated_at

Sync All MailerLite Data

source: MAILERLITE
target: MY_POSTGRES

defaults:
  mode: full-refresh
  object: mailerlite.{stream_name}

streams:
  '*':

If you are facing issues connecting, please reach out to us at [e-mail], on discord or open a Github Issue here.