This is a Subscriber in our system. Subscribers are the recipients of emails in our system.

Subscriber Status

An important concept is the subscriber's status.

Status	Description
Active	An active subscriber will receive emails if included in a mailing.
Inactive	An inactive subscriber has no permissions, and will not receive emails even if included in a mailing.
Unconfirmed	New subscribers can have this status if they have not yet clicked on the "confirm" email. This API cannot set a subscriber to this status.
Opt out	Our system has a strongly enforced opt-out mechanism.

To protect our reputation, once a subscriber has opted-out, by default it is not possible to opt them in again¹.

Subscribers can also be opted out by an administrator, or by our bounce detector, and via this API. These are softer opt-outs, and can be opted back in via an update call. If you set a subscriber to be opted-out, then all existing permissions will be removed.

Custom Fields

If you need to record information about a subscriber that doesn't fit with our built-in fields, you can create custom fields to hold this information. Custom fields have a data type (numeric, textual, date). In this documentation, you might see references to custom field names. These are place-holders for the arbitrary names your custom fields use.

External ID

The external ID field is specifically designed for use with the API. You can set it to any value you want. Generally, it would be set to the unique identifier you use in your own database of subscribers. Please note that the Poppulo system does not enforce uniqueness on this field. We do support fast listing by external id.

Tags

Tags are ways to arbitrarily group subscribers.

Topics

Some advanced emails will have content that is only relevant to some subscribers. We represent this by topic associations.

Permissions

A subscriber will receive email if they have a permission, and the permission is associated with the publication that is being sent.

Sections²

Some advanced emails will have content that is only relevant to some subscribers. We represent this by section associations.

Reviewer groups

Subscribers can be added to reviewer groups, which allows you to send test emails to them.

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Footnotes

1. We can delegate trust to the API to allow subscriber opt-outs to be overridden. If this is necessary for your integration, please contact our support team to discuss this. ↩

2. This is deprecated. Please use topics instead. ↩